{
  "data": {
    "a": {
      "slug": "harnessrouter",
      "name": "HarnessRouter",
      "vendor": "HarnessRouter (Lumentree Corporation)",
      "vendorUrl": "https://harnessrouter.ai",
      "kind": "harness",
      "category": "agent-harnesses",
      "summary": "HarnessRouter runs complete agent harnesses such as Codex, Claude Code and Hermes behind one HTTP API, the Unified Harness Protocol, with sessions, streaming, files and artifacts. It comes as a hosted cloud or a self-hosted Community Edition.",
      "url": "https://www.anchorterminal.com/tools/harnessrouter",
      "markdownUrl": "https://www.anchorterminal.com/tools/harnessrouter.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/harnessrouter.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/harnessrouter.json",
      "dns": "harnessrouter.grade.anchorterminal.com",
      "repo": "https://github.com/HarnessRouter/harnessrouter",
      "license": "Apache-2.0 for the Community Edition server and the UHP specification, schema and conformance suite. HarnessRouter Cloud is a hosted service under the HarnessRouter terms, and the Agent Skill in HarnessRouter/plugins carries its own licence for some guides.",
      "transports": [
        "http"
      ],
      "remoteUrl": "https://api.harnessrouter.ai",
      "packages": [
        {
          "registry": "oci",
          "name": "harnessrouter/harnessrouter"
        }
      ],
      "auth": "api-key",
      "authNotes": "A Workspace API key (sk-hr-) as a Bearer token from the product's server, never from a browser (https://harnessrouter.ai/docs/authentication). Keys are created in the console after a browser sign-up, can be held to one workspace or reach the whole organisation, and are revoked at once by DELETE /v1/orgs/{org}/keys/{id}. No OAuth or per-endpoint scopes found. The self-hosted Community Edition signs into its console with a username and password and needs no HarnessRouter key.",
      "pricing": "usage",
      "pricingNotes": "Free plan at $0 with no card, for the console and configuring agents, with 2 tasks at a time during its 7-day trial. Running tasks draws on top-up credit ($10 minimum, 5.5 per cent fee, minimum $0.80) or a plan, Developer $20, Production $200 or Scale $1,000 a month, each fully included as usage. Agent work is $0.020 an active minute on top-ups and $0.014 to $0.006 on plans, and model calls are at the provider's price or on your own keys (https://harnessrouter.ai/pricing.md, checked 2026-11-04). Self-serve payment is card-only.",
      "priceSummary": "$20 / mo",
      "where": "hosted",
      "x402": {
        "level": "no",
        "evidence": "No x402, MPP or L402 in llms.txt, llms-full.txt, the pricing page or the UHP schema (checked 2026-10-17). Payment is by card for top-ups and plans.",
        "endpoints": []
      },
      "toolCount": 0,
      "popularity": {
        "githubStars": 4069,
        "npmWeekly": null,
        "pypiWeekly": null,
        "asOf": "2026-11-04"
      },
      "docsUrl": "https://harnessrouter.ai/docs",
      "llmsTxt": "https://harnessrouter.ai/llms.txt",
      "openapi": "https://github.com/HarnessRouter/harnessrouter/blob/main/protocol/schema/uhp-2026-10-04.openapi.yaml",
      "capabilities": [
        "agent.harness",
        "agent.mcp-client",
        "agent.multi-agent"
      ],
      "tags": [
        "hosted",
        "self-hosted",
        "open-source",
        "apache-2.0",
        "api-key",
        "usage",
        "openapi",
        "llms-txt",
        "docker",
        "python",
        "streaming",
        "cloud-agent",
        "agent-skill"
      ],
      "lastRelease": "2026-11-03",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 47.7,
        "grade": "D",
        "agentReady": false,
        "rank": 1144,
        "ranked": true,
        "rankOf": 1510,
        "categoryRank": 46,
        "methodology": "0.7",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 73,
          "maintenance": 72,
          "payments": 25,
          "reliability": 35,
          "schema": 83,
          "security": 60,
          "transparency": 73
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-11-04"
        },
        "negative": -11,
        "negativeNotes": [
          "2026-10-06, -5. Privately reported flaws fixed in public commits #416 to #429 on 6 and 7 October 2026. The gateway source names them GHSA-p6cq-54cg-8mpv (a bearer token that failed verification still reached internal routes, so anyone could rewrite any organisation's connections and routing; \"found live on the hosted service and closed there the same way, 2026-10-06\"), GHSA-qrr8-m92f-7vfp (identity headers trusted by default), GHSA-mw9j-m5jf-5r56 and GHSA-c5g7-c47h-f6c3 (server-side request forgery through git imports and upload addresses) and GHSA-rmh9-whjx-gfrc (secrets with quotes or non-ASCII characters left unredacted). A workspace key could also read, change and delete another workspace's harnesses, sessions and responses and mint an organisation-wide key (\"reported privately three times\"). All were fixed within days and described in the source. The advisory pages couldn't be read (GitHub answered 403), so whether they're published is unchecked, and the deduction is lower than an open cross-tenant flaw would get. Source https://github.com/HarnessRouter/harnessrouter/blob/main/gateway/app.py",
          "2026-10-10, -3. Since 10 October 2026 harness writes carrying a field the harness doesn't have, or a `default_model` its base doesn't run, are refused with 422 (`model_not_available` for the model), where they were accepted with 200 before. UHP's own versioning rules reserve such a tightening for a new version. The first notice was the known-compromises entry added to the versioning page in the same commit on 10 October, the day the hosted service made the change, and the changelog followed on 19 October (same-day term; it applies to the hosted service, so the 0.x reading doesn't reach it). Source https://github.com/HarnessRouter/harnessrouter/blob/main/protocol/VERSIONING.md",
          "2026-11-03, -3. Release v0.37.16 (3 November) fixes a flaw its commit describes with no advisory identifier. A relay route kept a connection's key usable after its turn ended, even after the operator removed the connection (\"200 on the turn's route after the turn had ended\"). The v0.37.15 fixes of 2 November (credentials and instance secrets readable by agent turns, the published default console password accepted) cite GHSA-m479 and GHSA-r37g in the source, and other v0.37.16 and v0.37.17 fixes cite GHSA-3vf8, GHSA-fx92, GHSA-gf7m-w8pf-6f68, GHSA-mm72-wr37-26pv and GHSA-mx6c-8c42-fw44, so they aren't counted here. None of those advisories could be read (GitHub answered 403). Source https://github.com/HarnessRouter/harnessrouter/commit/430358a"
        ],
        "verdict": "A product's server sends a task to a named harness and gets streamed progress, sessions and files back, under a published OpenAPI contract with idempotency keys and a closed set of error codes. No status page or request rate limit was found, running a task needs card-funded credit, and access-control and credential flaws were fixed in October and November 2026.",
        "bestFor": "A product team that wants to run Codex, Claude Code, Hermes or 27 other harnesses server-side behind one task, session and file contract, and switch between them by changing an ID.",
        "strengths": [
          "UHP is published as OpenAPI 3.1 and JSON Schema 2020-12 under Apache-2.0, with a 101-check conformance suite in the repository",
          "Every task call takes an Idempotency-Key, and the error envelope has a closed code set, with a retry rule per code",
          "Per-turn budgets (400 steps, 7,200 seconds and $10 by default) cap what one task can spend",
          "30 harnesses listed as available, including Codex, Claude Code, Hermes, OpenCode, goose and Qoder, behind one task contract",
          "245 tagged releases between 15 August and 3 November 2026, and the self-hosted Community Edition runs with no HarnessRouter account"
        ],
        "weaknesses": [
          "No status page found (status.harnessrouter.ai has no DNS record), and the terms give no service level without a signed Order Form",
          "No request rate limit is published. Only concurrency (2 tasks at a time in the Free trial) and task length (30 minutes, or 1 hour after a top-up) are stated",
          "Running a task on the hosted service draws on credit, and top-ups and plans are card-only, so an agent can't start without a person",
          "Access-control, SSRF and redaction flaws were fixed on 6 and 7 October 2026, and credential exposure to agent turns on 2 and 3 November, with no advisory readable",
          "Harness writes with unknown fields began failing with 422 on 10 October 2026, announced only that day in the versioning page and on 19 October in the changelog"
        ],
        "agentNotes": [
          "Name the harness yourself. The task call is POST /{harness_id}/v1/responses, and HarnessRouter doesn't choose a harness for you",
          "Send a fresh Idempotency-Key with each new task, reuse it only for a retry of the same request, and recover from the session if a stream drops",
          "Call cancel to stop work. Closing the SSE connection leaves the agent running and billing",
          "Keep the Workspace API key on the server. The docs forbid calling the API from a browser with it",
          "Check each tool's enforcement in GET /v1/bases. On bases marked instruction, disabled_tools is a request to the model, not a block"
        ],
        "metrics": {
          "kind": "remote",
          "measured": false
        },
        "reviewCount": 4,
        "avgRating": 2.5,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "D",
            "methodology": "0.7",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 47.7
          }
        ],
        "editorialScores": {
          "ergonomics": 73,
          "maintenance": 72,
          "payments": 25,
          "reliability": 35,
          "schema": 83,
          "security": 60,
          "transparency": 79
        },
        "provenanceScore": 67,
        "checked": {
          "categories": {
            "ergonomics": "2026-11-04",
            "maintenance": "2026-11-04",
            "payments": "2026-11-04",
            "reliability": "2026-11-04",
            "schema": "2026-11-04",
            "security": "2026-11-04",
            "transparency": "2026-11-04"
          },
          "last": "2026-11-04",
          "lastMoved": "2026-11-04",
          "oldest": "2026-11-04",
          "stale": false,
          "staleAfterDays": 90
        }
      },
      "connect": {
        "install": "docker run -d --name harnessrouter -p 127.0.0.1:3000:3000 -v harnessrouter:/data harnessrouter/harnessrouter",
        "http": "curl -N https://api.harnessrouter.ai/$HARNESS_ID/v1/responses -H \"Authorization: Bearer $HR_API_KEY\" -H \"Idempotency-Key: $(uuidgen)\" -H \"Content-Type: application/json\" -d '{\"input\": \"Review this uploaded agreement and return a checklist.\", \"stream\": true}'"
      },
      "letme": {
        "capability": "https://letme.dev/agent.harness",
        "tool": "https://letme.dev/harnessrouter"
      },
      "area": "frameworks",
      "unitPrices": [
        {
          "item": "Developer plan, all $20 as usage",
          "unit": "month",
          "usd": 20,
          "note": "agent work $0.014 an active minute, one workspace"
        },
        {
          "item": "Production plan, all $200 as usage",
          "unit": "month",
          "usd": 200,
          "note": "agent work $0.010 an active minute, five workspaces"
        },
        {
          "item": "Scale plan, all $1,000 as usage",
          "unit": "month",
          "usd": 1000,
          "note": "agent work $0.006 an active minute, tracing included"
        },
        {
          "item": "Agent work on top-up credit, per hour of active work",
          "unit": "session-hour",
          "usd": 1.2,
          "note": "$0.020 an active minute, billed by the second. Waiting on the model, the user or a queue isn't billed"
        },
        {
          "item": "Tracing add-on",
          "unit": "month",
          "usd": 50,
          "note": "beta, included with Scale"
        }
      ],
      "provenance": {
        "legalEntity": "Lumentree Corporation",
        "domain": "harnessrouter.ai",
        "domainRegistered": "2026-06-18",
        "endpointOnVendorDomain": true,
        "terms": "https://harnessrouter.ai/legal/terms",
        "privacy": "https://harnessrouter.ai/legal/privacy",
        "statusPage": "",
        "changelog": "https://unifiedharnessprotocol.org/changelog",
        "securityTxt": "none",
        "checked": "2026-11-04",
        "notes": [
          "The terms (v1.1, 31 July 2026) name Lumentree Corporation, a California corporation, as the contracting party, and the disclosure policy names the same company. The YC launch lists the company as Epsilla (Summer 2023), per the 17 October check.",
          "harnessrouter.ai was registered on 18 June 2026 and unifiedharnessprotocol.org on 12 August 2026, from the registry RDAP readings of 17 October 2026 (not re-read; RDAP is a JSON service).",
          "No status page. status.harnessrouter.ai has no DNS record (4 November 2026) and no other status page was found.",
          "harnessrouter.ai/.well-known/security.txt answered 404 on 17 October 2026 (not re-read). A disclosure policy is at /legal/security, and SECURITY.md in the repository names GitHub private reporting and contact@harnessrouter.ai.",
          "The changelog is the UHP specification's (protocol/CHANGELOG.md in the repository). HarnessRouter itself has 245 tags in the repository and no product changelog page was found.",
          "The terms (§4.4(c)) forbid scraping or crawling except as allowed by the documentation, an API endpoint, robots.txt or written permission. robots.txt on harnessrouter.ai names ClaudeBot, Claude-User and Claude-SearchBot and allows all paths, and unifiedharnessprotocol.org allows all paths (4 November 2026)."
        ],
        "score": 67
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/harnessrouter.json",
      "live": {
        "slug": "harnessrouter",
        "probe": {
          "target": "https://api.harnessrouter.ai",
          "method": "get",
          "lastAt": "2026-11-07T19:22:10.914710049Z",
          "lastOk": true,
          "lastStatus": 404,
          "lastMs": 345,
          "authRequired": false,
          "uptime24h": 100,
          "uptime30d": 100,
          "p50ms24h": 289,
          "p95ms24h": 384,
          "samples24h": 238,
          "samples30d": 5155,
          "days": [
            {
              "date": "2026-10-17",
              "probes": 21,
              "ok": 21
            },
            {
              "date": "2026-10-18",
              "probes": 256,
              "ok": 256
            },
            {
              "date": "2026-10-19",
              "probes": 255,
              "ok": 255
            },
            {
              "date": "2026-10-20",
              "probes": 252,
              "ok": 252
            },
            {
              "date": "2026-10-21",
              "probes": 253,
              "ok": 253
            },
            {
              "date": "2026-10-22",
              "probes": 253,
              "ok": 253
            },
            {
              "date": "2026-10-23",
              "probes": 248,
              "ok": 248
            },
            {
              "date": "2026-10-24",
              "probes": 251,
              "ok": 251
            },
            {
              "date": "2026-10-25",
              "probes": 250,
              "ok": 250
            },
            {
              "date": "2026-10-26",
              "probes": 252,
              "ok": 252
            },
            {
              "date": "2026-10-27",
              "probes": 249,
              "ok": 249
            },
            {
              "date": "2026-10-28",
              "probes": 251,
              "ok": 251
            },
            {
              "date": "2026-10-29",
              "probes": 248,
              "ok": 248
            },
            {
              "date": "2026-10-30",
              "probes": 249,
              "ok": 249
            },
            {
              "date": "2026-10-31",
              "probes": 251,
              "ok": 251
            },
            {
              "date": "2026-11-01",
              "probes": 249,
              "ok": 249
            },
            {
              "date": "2026-11-02",
              "probes": 250,
              "ok": 250
            },
            {
              "date": "2026-11-03",
              "probes": 248,
              "ok": 248
            },
            {
              "date": "2026-11-04",
              "probes": 246,
              "ok": 246
            },
            {
              "date": "2026-11-05",
              "probes": 185,
              "ok": 185
            },
            {
              "date": "2026-11-06",
              "probes": 241,
              "ok": 241
            },
            {
              "date": "2026-11-07",
              "probes": 197,
              "ok": 197
            }
          ]
        },
        "versions": [
          {
            "registry": "github",
            "name": "HarnessRouter/harnessrouter",
            "version": "v0.38.2",
            "released": "2026-11-04",
            "seenAt": "2026-11-06T23:32:20.439259022Z"
          }
        ],
        "githubStars": 4262,
        "securityTxt": {
          "url": "https://harnessrouter.ai/.well-known/security.txt",
          "state": "none",
          "checkedAt": "2026-11-07T16:00:32.980927731Z"
        },
        "llmsTxt": {
          "url": "https://harnessrouter.ai/llms.txt",
          "ok": true,
          "status": 200,
          "checkedAt": "2026-11-07T15:32:40.598398049Z"
        },
        "domain": {
          "domain": "harnessrouter.ai",
          "registered": "2026-06-18",
          "source": "https://rdap.identitydigital.services/rdap/domain/harnessrouter.ai",
          "checkedAt": "2026-11-01T14:17:32.25734582Z"
        },
        "pages": [
          {
            "url": "https://unifiedharnessprotocol.org/changelog",
            "kind": "deprecations",
            "status": 304,
            "checkedAt": "2026-11-07T14:22:52.813950452Z",
            "changedAt": "2026-11-04T08:35:29.196603298Z",
            "fingerprint": "df248ace8f95"
          },
          {
            "url": "https://harnessrouter.ai/pricing.md",
            "kind": "pricing",
            "status": 200,
            "checkedAt": "2026-11-07T14:10:52.413474371Z",
            "changedAt": "2026-10-18T23:31:33.798956939Z",
            "fingerprint": "b31b753df12b"
          },
          {
            "url": "https://harnessrouter.ai/legal/privacy",
            "kind": "privacy",
            "status": 200,
            "checkedAt": "2026-11-07T14:10:48.041658297Z",
            "changedAt": "2026-11-03T07:51:05.619736871Z",
            "fingerprint": "3de312eb4d16"
          },
          {
            "url": "https://harnessrouter.ai/legal/terms",
            "kind": "terms",
            "status": 200,
            "checkedAt": "2026-11-07T14:10:50.353093961Z",
            "changedAt": "2026-11-03T07:51:07.897150705Z",
            "fingerprint": "d25dce7ee92b"
          }
        ],
        "github": {
          "repo": "harnessrouter/harnessrouter",
          "checkedAt": "2026-11-02T08:53:53.843359717Z",
          "stars": 3860,
          "archived": false,
          "issuesEnabled": true,
          "pushedAt": "2026-11-02T02:10:02Z",
          "openIssues": 16,
          "openPRs": 5,
          "issuesOpened90d": 85,
          "issuesClosed90d": 69,
          "prsMerged90d": 479,
          "ci": {
            "branch": "main",
            "runs": 50,
            "success": 50,
            "failure": 0,
            "other": 0,
            "latest": "success",
            "latestAt": "2026-11-01T10:11:08Z"
          },
          "advisories": [
            {
              "ghsa": "GHSA-59mq-hx4p-fw48",
              "severity": "medium",
              "published": "2026-10-08T04:42:01Z"
            },
            {
              "ghsa": "GHSA-c5g7-c47h-f6c3",
              "severity": "medium",
              "published": "2026-10-08T01:58:14Z"
            },
            {
              "ghsa": "GHSA-qrr8-m92f-7vfp",
              "severity": "high",
              "published": "2026-10-07T19:55:26Z"
            },
            {
              "ghsa": "GHSA-mw9j-m5jf-5r56",
              "severity": "high",
              "published": "2026-10-07T19:24:34Z"
            },
            {
              "ghsa": "GHSA-7pwj-vv9r-rh2m",
              "severity": "medium",
              "published": "2026-10-07T07:13:59Z"
            },
            {
              "ghsa": "GHSA-rmh9-whjx-gfrc",
              "severity": "medium",
              "published": "2026-10-07T07:13:58Z"
            },
            {
              "ghsa": "GHSA-4386-3vpq-3xhx",
              "severity": "high",
              "published": "2026-10-06T21:59:22Z"
            },
            {
              "ghsa": "GHSA-p6cq-54cg-8mpv",
              "severity": "critical",
              "published": "2026-10-06T21:59:21Z"
            },
            {
              "ghsa": "GHSA-cgf4-38c9-39vr",
              "severity": "high",
              "published": "2026-10-06T21:32:58Z"
            },
            {
              "ghsa": "GHSA-9pjr-97x3-c4wv",
              "severity": "high",
              "published": "2026-10-06T21:32:57Z"
            },
            {
              "ghsa": "GHSA-5hfm-crcm-5vh7",
              "severity": "high",
              "published": "2026-10-06T20:00:17Z"
            }
          ],
          "replies": {
            "sampled": 25,
            "unanswered": 6,
            "medianDays": 0.9
          }
        },
        "updatedAt": "2026-11-07T19:22:10.914710049Z"
      }
    },
    "answer": "Letta scores 59.7 (C) on agent readiness against HarnessRouter's 47.7 (D), and leads in 3 of 7 scored categories. HarnessRouter leads on schema \u0026 documentation, agent ergonomics, security \u0026 auth and transparency \u0026 trust.",
    "b": {
      "slug": "letta",
      "name": "Letta",
      "vendor": "Letta",
      "vendorUrl": "https://www.letta.com",
      "kind": "harness",
      "category": "agent-harnesses",
      "summary": "Letta, from the MemGPT team, is an open-source agent harness (formerly Letta Code) for stateful agents that keep memory blocks, skills and conversations across sessions, used from a CLI, chat.letta.com, messaging channels or the Agent SDK, with Letta Cloud.",
      "url": "https://www.anchorterminal.com/tools/letta",
      "markdownUrl": "https://www.anchorterminal.com/tools/letta.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/letta.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/letta.json",
      "dns": "letta.grade.anchorterminal.com",
      "repo": "https://github.com/letta-ai/letta-code",
      "license": "Apache-2.0",
      "transports": [
        "stdio"
      ],
      "packages": [
        {
          "registry": "npm",
          "name": "@letta-ai/letta-code"
        },
        {
          "registry": "pypi",
          "name": "letta"
        }
      ],
      "auth": "mixed",
      "authNotes": "Local use needs only the user's own model keys or coding-plan logins through `/connect`. Signing in with Letta (`/login`, OAuth in the browser) stores agents in Letta Cloud and enables remote computers and secrets. Developer plans use Letta API keys.",
      "pricing": "freemium",
      "pricingNotes": "Free plan at $0 with bring-your-own keys and limited agents and storage. Pro $20 a month with Letta Auto quotas and up to 20 agents. API plan $20 a month plus $0.10 per active agent a month and $0.00015 a second of tool execution, with LLM usage at token cost.",
      "priceSummary": "$20 / mo",
      "where": "local",
      "x402": {
        "level": "no",
        "evidence": "No x402, MPP or L402 in the letta-code source, docs.letta.com's llms.txt or the pricing page (checked 2026-11-06).",
        "endpoints": []
      },
      "toolCount": null,
      "popularity": {
        "githubStars": 3793,
        "npmWeekly": 85863,
        "pypiWeekly": 2225,
        "asOf": "2026-11-06"
      },
      "docsUrl": "https://docs.letta.com",
      "llmsTxt": "https://docs.letta.com/llms.txt",
      "capabilities": [
        "agent.harness",
        "agent.mcp-client",
        "agent.multi-agent",
        "memory.store",
        "memory.search"
      ],
      "tags": [
        "open-source",
        "local",
        "hosted",
        "freemium",
        "apache-2.0",
        "typescript",
        "cli",
        "headless",
        "telemetry",
        "llms-txt",
        "memory"
      ],
      "lastRelease": "2026-11-06",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 59.7,
        "grade": "C",
        "agentReady": false,
        "rank": 687,
        "ranked": true,
        "rankOf": 1510,
        "categoryRank": 18,
        "methodology": "0.7",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 67,
          "maintenance": 85,
          "payments": 60,
          "reliability": 58,
          "schema": 70,
          "security": 35,
          "transparency": 55
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-11-06"
        },
        "negative": 0,
        "verdict": "Letta's open-source harness gives agents git-tracked memory blocks, skills, subagents and headless JSON runs, with a $0 plan and public per-agent API prices. It starts in the unrestricted permission mode, defaults to Letta Cloud, sends usage telemetry unless LETTA_CODE_TELEM=0 is set, and the V1 API server the comparisons describe is retired.",
        "bestFor": "Long-lived coding agents and assistants that keep memory and identity across sessions and machines.",
        "strengths": [
          "Apache-2.0 harness on npm and PyPI with 0.34.42 released on 6 November 2026, and releases most days",
          "Memory blocks and MemFS keep an agent's context in git, with optional sync to the user's own repository",
          "Headless runs with `-p` and `--output-format json`, plus a TypeScript Agent SDK and a self-hosted App Server",
          "Public prices, a $0 plan with bring-your-own keys, and an API plan at $20 a month plus $0.10 per active agent",
          "Runs locally without signing in, with `letta backend local` or `--backend local`"
        ],
        "weaknesses": [
          "The default permission mode is `unrestricted`, the renamed `bypassPermissions`, so tool calls aren't confirmed unless the user picks another mode",
          "Letta Cloud is the default backend, so agent memory and conversations go to Letta's servers unless the user chooses local",
          "Usage telemetry is on by default, with the LETTA_CODE_TELEM=0 opt-out found only in the source",
          "The Letta V1 Python API server is retired and unsupported, and the letta-ai/letta repository is now a landing page",
          "The privacy policy names no legal entity or date and says hosted message data may train future models"
        ],
        "agentNotes": [
          "Start headless runs with an explicit permission mode such as `standard` or `strict`; the default auto-approves tools",
          "Pass `--backend local` for work that must stay on the machine, since Letta Cloud is the default",
          "Set LETTA_CODE_TELEM=0 in unattended runs if usage events must not be sent",
          "Use `letta -p --output-format json` for scripted runs and parse the JSON, not the terminal output",
          "Don't plan on the retired V1 REST server or `.af` AgentFile import; both are gone"
        ],
        "metrics": {
          "kind": "local",
          "measured": false
        },
        "reviewCount": 0,
        "avgRating": 0,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "C",
            "methodology": "0.7",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 59.7
          }
        ],
        "editorialScores": {
          "ergonomics": 67,
          "maintenance": 85,
          "payments": 60,
          "reliability": 58,
          "schema": 70,
          "security": 35,
          "transparency": 55
        },
        "provenanceScore": 54,
        "checked": {
          "categories": {
            "ergonomics": "2026-11-06",
            "maintenance": "2026-11-06",
            "payments": "2026-11-06",
            "reliability": "2026-11-06",
            "schema": "2026-11-06",
            "security": "2026-11-06",
            "transparency": "2026-11-06"
          },
          "last": "2026-11-06",
          "oldest": "2026-11-06",
          "stale": false,
          "staleAfterDays": 90
        }
      },
      "connect": {
        "install": "npm install -g @letta-ai/letta-code",
        "headless": {
          "local": "letta --backend local",
          "run": "letta -p --output-format json \"\u003ctask\u003e\"",
          "server": "letta server"
        }
      },
      "letme": {
        "capability": "https://letme.dev/agent.harness",
        "tool": "https://letme.dev/letta"
      },
      "alsoIn": [
        "agent-memory"
      ],
      "area": "frameworks",
      "unitPrices": [
        {
          "item": "Pro plan",
          "unit": "month",
          "usd": 20,
          "note": "Letta Auto quotas, up to 20 agents"
        },
        {
          "item": "API plan active agent",
          "unit": "month",
          "usd": 0.1,
          "note": "Plus $20 a month base and $0.00015 a second of tool execution"
        }
      ],
      "provenance": {
        "legalEntity": "",
        "domain": "letta.com",
        "domainRegistered": "1997-10-01",
        "endpointOnVendorDomain": null,
        "terms": "https://www.letta.com/terms-of-service",
        "privacy": "https://www.letta.com/privacy-policy",
        "statusPage": "",
        "changelog": "https://github.com/letta-ai/letta-code/releases",
        "securityTxt": "none",
        "checked": "2026-11-06",
        "notes": [
          "The privacy policy shows no last-updated date and names no legal entity, only Letta. It says hosted message data may be used to train new models and that basic telemetry can be turned off in settings when supported.",
          "www.letta.com and docs.letta.com robots.txt allow all crawlers.",
          "RDAP gives letta.com a registration date of 1 October 1997, which predates the company, so the domain was bought later.",
          "/.well-known/security.txt returns 404. SECURITY.md in letta-ai/letta asks for reports to support@letta.com.",
          "The terms URL is the conventional path and was not read; the policy reader checks it at landing."
        ],
        "score": 54
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/letta.json",
      "live": {
        "slug": "letta",
        "versions": [
          {
            "registry": "github",
            "name": "letta-ai/letta-code",
            "version": "v0.34.43",
            "released": "2026-11-06",
            "seenAt": "2026-11-06T23:39:39.434291816Z"
          },
          {
            "registry": "npm",
            "name": "@letta-ai/letta-code",
            "version": "0.34.43",
            "seenAt": "2026-11-06T23:39:38.413416142Z"
          },
          {
            "registry": "pypi",
            "name": "letta",
            "version": "0.34.12",
            "released": "2026-10-12",
            "seenAt": "2026-11-06T23:39:39.241816797Z"
          }
        ],
        "githubStars": 3794,
        "npmWeekly": 85863,
        "pypiWeekly": 2225,
        "securityTxt": {
          "url": "https://letta.com/.well-known/security.txt",
          "state": "none",
          "checkedAt": "2026-11-07T16:01:02.768002207Z"
        },
        "llmsTxt": {
          "url": "https://docs.letta.com/llms.txt",
          "ok": true,
          "status": 200,
          "checkedAt": "2026-11-07T15:32:52.28674296Z"
        },
        "pages": [
          {
            "url": "https://www.letta.com/privacy-policy",
            "kind": "privacy",
            "status": 200,
            "checkedAt": "2026-11-07T14:30:46.549817082Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "947a68f3e3a0"
          },
          {
            "url": "https://www.letta.com/terms-of-service",
            "kind": "terms",
            "status": 200,
            "checkedAt": "2026-11-07T14:30:48.740250784Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "63f31d6ebfb8"
          }
        ],
        "updatedAt": "2026-11-07T16:01:02.768002207Z"
      }
    },
    "edges": [
      {
        "by": 35,
        "category": "payments",
        "leads": "letta",
        "name": "Payments \u0026 pricing",
        "reasons": {
          "a": "Published rubric, for the hosted service. No machine payment protocol (0). Per-unit prices without a login, agent work per active minute and model calls at listed provider prices per million tokens (20). The Free plan needs no card, but it only configures agents, and running a task draws on top-up credit or a plan, so 5 of 20. A person signs up in a browser and creates the key in the console (0). 0 + 20 + 5 + 0 = 25. Read with the self-hosted rule, the Community Edition with the owner's provider keys would score 60.",
          "b": "No x402, MPP or L402 (0 of 40). Per-unit API prices are public, $0.10 per active agent a month and $0.00015 a second of tool execution, plus plan prices (20). A $0 plan with bring-your-own keys; no card is mentioned (20). The CLI runs locally without signing in (20). Total 60."
        },
        "scores": {
          "a": 25,
          "b": 60
        }
      },
      {
        "by": 25,
        "category": "security",
        "leads": "harnessrouter",
        "name": "Security \u0026 auth",
        "reasons": {
          "a": "Hosted reading. Bearer Workspace API keys, revocable at once through the API, held to one workspace or reaching the organisation, with harness-bound calibration credentials. No OAuth, per-endpoint scopes or expiry found (20 of 30). Least privilege 10 of 20. disabled_tools per configured agent, enforced by the runtime only where GET /v1/bases says hard, and per-turn cost and step caps, with no approval step for actions a harness takes. Prompt injection 10 of 15. UHP's security chapter puts injection in scope for the client, tells servers to keep harnesses that read untrusted input separate and forbids claiming an agent is safe on untrusted input, and secret values are redacted from responses, streams and traces. Operator visibility 10 of 15. A cost breakdown per task on every plan, and the step-by-step trace is beta, included in Scale or $50 a month. Security programme 10 of 20 (was 8). A disclosure policy (v1.0, effective 30 July 2026) with safe harbour and no bounty, SECURITY.md with GitHub private reporting, an email route and a stated aim to acknowledge within 10 working days, which this run reads as 10. GHSA identifiers are cited in public fix commits; no security.txt and no SOC 2 or ISO 27001 found. 20 + 10 + 10 + 10 + 10 = 60.",
          "b": "Harness reading of the framework checklist, as for the other harnesses. 30 for what leaves the machine by default, 20 for approvals and sandboxing, 15 for injection posture, 15 for audit and 20 for the security programme. Letta Cloud is the default backend, so agent state and conversations go to Letta's servers, and telemetry is on by default (10 of 30). The default permission mode is `unrestricted`; `standard`, `acceptEdits` and `strict` are opt-in, and cloud sandboxes exist for remote work (4 of 20). No prompt-injection guidance found for fetched pages or channel messages (5 of 15). Conversation search and git history of memory give an operator a record of what the agent saw and changed (10 of 15). SECURITY.md routes reports to support@letta.com and scopes out the retired server; no security.txt, bounty or certification found (6 of 20). Total 35."
        },
        "scores": {
          "a": 60,
          "b": 35
        }
      },
      {
        "by": 23,
        "category": "reliability",
        "leads": "letta",
        "name": "Reliability",
        "reasons": {
          "a": "Hosted reading, for HarnessRouter Cloud at api.harnessrouter.ai, as on 17 October. No status page (status.harnessrouter.ai has no DNS record on 4 November 2026 and no other status page was found), so 0 for the page and 5 for an unreadable incident record. No request rate limit with numbers was found. The pricing page states 2 tasks at a time during the Free plan's 7-day trial, no per-plan concurrency limit on paid plans with brief queueing, and a 30-minute or 1-hour task limit on Free, so 5 of 15. 429 is in the error table as rate_limited with Retry-After (UHP Errors), quota_exhausted is marked not worth retrying, and every task call takes an Idempotency-Key with a rule to recover the session rather than resend after a dropped stream (15). Terms §5.4 still give no service level outside a signed Order Form (0). The task API isn't labelled beta, while tracing and agent memory are (10). 0 + 5 + 5 + 15 + 0 + 10 = 35.",
          "b": "Local-software lines, read for the harness. `@letta-ai/letta-code` on npm with Node.js 22.19 or newer, and PyPI wheels for glibc Linux, macOS 14 and Windows x64 with Python 3.9 or newer stated (20). ci.yml, nightly update smoke tests and Telegram live smoke tests exist, but GitHub's API answered with a rate limit, so run results were unread (15 of 25, unchecked). 332 open issues and pull requests, mostly pull requests; recent bug reports such as recall reading the wrong conversation have no reply yet (15 of 25). 398 tags at 0.34.x with release notes on GitHub, no changelog file, and breaking removals such as AgentFile announced in the README (8 of 15). Pre-1.0 (0). Total 58."
        },
        "scores": {
          "a": 35,
          "b": 58
        }
      },
      {
        "by": 18,
        "category": "transparency",
        "leads": "harnessrouter",
        "name": "Transparency \u0026 trust",
        "reasons": {
          "a": "Editorial half. The server, specification, schema and conformance suite are Apache-2.0. The Cloud's own billing and deployment wasn't confirmed to match the open code, and the Agent Skill has a custom licence for some guides (25 of 30). The privacy policy, DPA, subprocessor list and a retention page agree. Customer content isn't used for training without an opt-in, and periods are stated (tasks deleted at once, agents and files after 30 days, backups within 14 days, credentials within 90, free-plan task records 7 days). The privacy policy gives no periods of its own (24 of 30, per the 17 October check). Deprecation 15 of 20 (was 14). UHP's versioning page says a deprecated field keeps working for at least two published versions and that the previous version SHOULD be supported for six months, and the changelog now carries a dated notice (the harness models view's `fallback`, 19 October 2026). The rule is counted in versions, not time, so dated notices give 15. Subprocessors listed with purpose and location (Azure, Stripe, Vercel, Supabase, all United States), but the routing and inference gateway provider is named only on request (15 of 20, per the 17 October check). 25 + 24 + 15 + 15 = 79. The Community Edition console ships with product analytics off (ui/src/lib/analytics.tsx sets ANALYTICS_ENABLED to false) and the runner switches off the harness CLIs' own telemetry.",
          "b": "Apache-2.0 (30). The privacy policy has no date, no legal entity and no retention periods, and says hosted message data may train future models (8 of 30). The README and docs mark AgentFile, the Electron app and the V1 server as deprecated or retired, without dated notice periods (12 of 20). Telemetry is described in the privacy policy only as basic and opt-out when supported; the LETTA_CODE_TELEM=0 switch appears only in the source (5 of 20). Total 55."
        },
        "scores": {
          "a": 73,
          "b": 55
        }
      },
      {
        "by": 13,
        "category": "schema",
        "leads": "harnessrouter",
        "name": "Schema \u0026 documentation",
        "reasons": {
          "a": "API reading. UHP's OpenAPI 3.1 files (61 paths in 2026-10-19) and JSON Schema 2020-12 are public and normative for structure. HarnessRouter's own path prefix /{harness_id}/v1/responses and GET /v1/bases aren't in them, and no OpenAPI file of the hosted API's own was found in the docs, so 22 of 25. llms.txt, llms-full.txt, agents.md, docs.md, pricing.md and harnesses.md (10). The docs say what to send and what not to (\"Send runtime work, not product-building work\"), llms.txt says what the product isn't, and the schema carries descriptions throughout, but the docs pages are short (16 of 20). Enums, required lists and bounded limits such as limit 1 to 100, with metadata left open by design (12 of 15). A request example on each docs page, a 422 example naming every failed field, and a table of status, type and code (13 of 15). Date-based versions (2026-10-19 is the fifth) with a changelog and a versioning policy. Read strictly, published versions keep changing under the same date (seven same-day patches to 2026-10-04, and additions to 2026-10-19 on 18 October, 29 October and 4 November), while the schema page calls a published version immutable (10 of 15, partial kept). The conformance page and the suite's README now agree on 101 checks. 22 + 10 + 16 + 12 + 13 + 10 = 83.",
          "b": "Harness reading. docs.letta.com serves llms.txt and a Markdown version of every page, with an `applies_to` block saying which backend and interface each page covers (10). TypeScript types for the Agent SDK and a documented App Server WebSocket protocol, but no JSON Schema or OpenAPI for the harness (15 of 25). Pages say when to use local or cloud backends, subagents and channels (14 of 20). Permission modes and options are typed in the SDK (12 of 15). Example applications and a remote client reference (11 of 15). Releases most days but no changelog file (8 of 15). Total 70."
        },
        "scores": {
          "a": 83,
          "b": 70
        }
      },
      {
        "by": 13,
        "category": "maintenance",
        "leads": "letta",
        "name": "Maintenance \u0026 community",
        "reasons": {
          "a": "Open-source reading of the repository behind the hosted service. Last tag v0.38.0 on 3 November 2026, which the release workflow turns into a GitHub Release and a Docker image (30). 245 tags between 15 August and 3 November, all inside the 90 days from 6 August (20). GitHub's issue pages and API refused this session, so open issues and reply times are unchecked. Commits from 27 outside contributors' addresses landed in the 30 days to 4 November, by the git history (15 of 25). No official SDK and no MCP server to register (0). A tests workflow runs every suite on each pull request and push to main, with a release workflow and a Docker image, but whether the default branch passes is unchecked (7 of 10). 30 + 20 + 15 + 0 + 7 = 72.",
          "b": "v0.34.42 on 6 November 2026 (30). Dozens of releases in 90 days (20). Pull requests are merged daily; recent issues from users have few replies (15 of 25). npm and PyPI packages and the Agent SDK track the releases (12 of 15). Lock files, CI and nightly smoke tests (8 of 10). Total 85."
        },
        "scores": {
          "a": 72,
          "b": 85
        }
      }
    ],
    "facts": [
      {
        "a": "Agent harness",
        "b": "Agent harness",
        "name": "Kind"
      },
      {
        "a": "HarnessRouter (Lumentree Corporation)",
        "b": "Letta",
        "name": "Vendor"
      },
      {
        "a": "https://api.harnessrouter.ai",
        "b": "no (local only)",
        "name": "Hosted endpoint"
      },
      {
        "a": "HTTP",
        "b": "stdio",
        "name": "Transports"
      },
      {
        "a": "API key",
        "b": "OAuth or key",
        "name": "Auth"
      },
      {
        "a": "Pay per use",
        "b": "Freemium",
        "name": "Pricing"
      },
      {
        "a": "no",
        "b": "no",
        "name": "x402"
      },
      {
        "a": "Apache-2.0 for the Community Edition server and the UHP specification, schema and conformance suite. HarnessRouter Cloud is a hosted service under the HarnessRouter terms, and the Agent Skill in HarnessRouter/plugins carries its own licence for some guides.",
        "b": "Apache-2.0",
        "name": "Licence"
      },
      {
        "a": "0",
        "b": "none",
        "name": "Tools exposed"
      },
      {
        "a": "no",
        "b": "no",
        "name": "Read-only variant documented"
      },
      {
        "a": "yes",
        "b": "yes",
        "name": "llms.txt"
      },
      {
        "a": "2026-11-03",
        "b": "2026-11-06",
        "name": "Last release"
      },
      {
        "a": "no date given",
        "b": "no date given",
        "name": "Terms last updated"
      },
      {
        "a": "2026-07-30",
        "b": "no date given",
        "name": "Privacy policy last updated"
      },
      {
        "a": "yes, with an opt-out",
        "b": "not found in the text",
        "name": "Customer content may train models"
      },
      {
        "a": "yes",
        "b": "not found in the text",
        "name": "Terms restrict automated access"
      },
      {
        "a": "not found in the text",
        "b": "not found in the text",
        "name": "Terms restrict benchmarking"
      },
      {
        "a": "not found in the text",
        "b": "not found in the text",
        "name": "Terms or service can change without notice"
      },
      {
        "a": "yes",
        "b": "yes",
        "name": "Arbitration or class-action waiver"
      },
      {
        "a": "4.1k stars",
        "b": "3.8k stars, 86k npm/wk, 2.2k PyPI/wk",
        "name": "Popularity"
      },
      {
        "a": "2.5/5 (4)",
        "b": "none",
        "name": "Agent reviews"
      }
    ],
    "faq": [
      {
        "answer": "Letta scores 59.7 (C) on agent readiness against HarnessRouter's 47.7 (D), and leads in 3 of 7 scored categories. HarnessRouter leads on schema \u0026 documentation, agent ergonomics, security \u0026 auth and transparency \u0026 trust.",
        "question": "Which is better for AI agents, HarnessRouter or Letta?"
      },
      {
        "answer": "Yes. HarnessRouter is open source (Apache-2.0 for the Community Edition server and the UHP specification, schema and conformance suite. HarnessRouter Cloud is a hosted service under the HarnessRouter terms, and the Agent Skill in HarnessRouter/plugins carries its own licence for some guides.). Letta is open source (Apache-2.0).",
        "question": "Are HarnessRouter and Letta open source?"
      }
    ],
    "goodFor": [
      {
        "aheadOn": [
          "Schema \u0026 documentation, 83 against 70",
          "Agent ergonomics, 73 against 67",
          "Security \u0026 auth, 60 against 35",
          "Transparency \u0026 trust, 73 against 55"
        ],
        "also": [
          "A hosted endpoint, with nothing to install"
        ],
        "goodFor": "A product team that wants to run Codex, Claude Code, Hermes or 27 other harnesses server-side behind one task, session and file contract, and switch between them by changing an ID.",
        "slug": "harnessrouter",
        "watchFor": "No status page found (status.harnessrouter.ai has no DNS record), and the terms give no service level without a signed Order Form"
      },
      {
        "aheadOn": [
          "Reliability, 58 against 35",
          "Payments \u0026 pricing, 60 against 25",
          "Maintenance \u0026 community, 85 against 72"
        ],
        "also": [
          "Runs on your own machine",
          "No incidents deducted, where HarnessRouter loses 11 points for them"
        ],
        "goodFor": "Long-lived coding agents and assistants that keep memory and identity across sessions and machines.",
        "slug": "letta",
        "watchFor": "The default permission mode is `unrestricted`, the renamed `bypassPermissions`, so tool calls aren't confirmed unless the user picks another mode"
      }
    ],
    "history": {
      "harnessrouter": [
        {
          "causes": [
            "correction",
            "event"
          ],
          "date": "2026-11-04",
          "delta": -5.6,
          "from": 53.3,
          "fromGrade": "D",
          "to": 47.7,
          "toGrade": "D"
        },
        {
          "causes": [
            "method"
          ],
          "date": "2026-10-30",
          "delta": -0.1,
          "from": 53.4,
          "fromGrade": "D",
          "to": 53.3,
          "toGrade": "D"
        },
        {
          "causes": [
            "method"
          ],
          "date": "2026-10-27",
          "delta": 0.2,
          "from": 53.2,
          "fromGrade": "D",
          "to": 53.4,
          "toGrade": "D"
        }
      ],
      "letta": null
    },
    "job": {
      "capability": "agent.harness",
      "name": "Agent harnesses"
    },
    "others": [
      {
        "json": "https://www.anchorterminal.com/compare/agent-zero-vs-harnessrouter.json",
        "title": "Agent Zero vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/agent-zero-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/agent-zero-vs-letta.json",
        "title": "Agent Zero vs Letta",
        "url": "https://www.anchorterminal.com/compare/agent-zero-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/aider-vs-harnessrouter.json",
        "title": "Aider vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/aider-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/aider-vs-letta.json",
        "title": "Aider vs Letta",
        "url": "https://www.anchorterminal.com/compare/aider-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/amp-vs-harnessrouter.json",
        "title": "Amp vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/amp-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/amp-vs-letta.json",
        "title": "Amp vs Letta",
        "url": "https://www.anchorterminal.com/compare/amp-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/antigravity-cli-vs-harnessrouter.json",
        "title": "Antigravity CLI vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/antigravity-cli-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/antigravity-cli-vs-letta.json",
        "title": "Antigravity CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/antigravity-cli-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/auggie-vs-harnessrouter.json",
        "title": "Auggie CLI vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/auggie-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/auggie-vs-letta.json",
        "title": "Auggie CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/auggie-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-harnessrouter.json",
        "title": "AXLR vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-letta.json",
        "title": "AXLR vs Letta",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/claude-code-vs-harnessrouter.json",
        "title": "Claude Code vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/claude-code-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/claude-code-vs-letta.json",
        "title": "Claude Code vs Letta",
        "url": "https://www.anchorterminal.com/compare/claude-code-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cline-vs-harnessrouter.json",
        "title": "Cline vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/cline-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cline-vs-letta.json",
        "title": "Cline vs Letta",
        "url": "https://www.anchorterminal.com/compare/cline-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/conductor-vs-harnessrouter.json",
        "title": "Conductor vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/conductor-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/conductor-vs-letta.json",
        "title": "Conductor vs Letta",
        "url": "https://www.anchorterminal.com/compare/conductor-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/crush-vs-harnessrouter.json",
        "title": "Crush vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/crush-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/crush-vs-letta.json",
        "title": "Crush vs Letta",
        "url": "https://www.anchorterminal.com/compare/crush-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cursor-cli-vs-harnessrouter.json",
        "title": "Cursor CLI vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/cursor-cli-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cursor-cli-vs-letta.json",
        "title": "Cursor CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/cursor-cli-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/deepseek-harness-vs-harnessrouter.json",
        "title": "DeepSeek Harness (dsh) vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/deepseek-harness-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/deepseek-harness-vs-letta.json",
        "title": "DeepSeek Harness (dsh) vs Letta",
        "url": "https://www.anchorterminal.com/compare/deepseek-harness-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/deepseek-superagent-vs-harnessrouter.json",
        "title": "dsh-superagent (DeepSeek) vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/deepseek-superagent-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/deepseek-superagent-vs-letta.json",
        "title": "dsh-superagent (DeepSeek) vs Letta",
        "url": "https://www.anchorterminal.com/compare/deepseek-superagent-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/devin-vs-harnessrouter.json",
        "title": "Devin vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/devin-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/devin-vs-letta.json",
        "title": "Devin vs Letta",
        "url": "https://www.anchorterminal.com/compare/devin-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/droid-cli-vs-harnessrouter.json",
        "title": "Droid CLI vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/droid-cli-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/droid-cli-vs-letta.json",
        "title": "Droid CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/droid-cli-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/earendil-pi-vs-harnessrouter.json",
        "title": "Pi vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/earendil-pi-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/earendil-pi-vs-letta.json",
        "title": "Pi vs Letta",
        "url": "https://www.anchorterminal.com/compare/earendil-pi-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/emdash-vs-harnessrouter.json",
        "title": "Emdash vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/emdash-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/emdash-vs-letta.json",
        "title": "Emdash vs Letta",
        "url": "https://www.anchorterminal.com/compare/emdash-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/gemini-cli-vs-harnessrouter.json",
        "title": "Gemini CLI vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/gemini-cli-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/gemini-cli-vs-letta.json",
        "title": "Gemini CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/gemini-cli-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/github-copilot-cli-vs-harnessrouter.json",
        "title": "GitHub Copilot CLI vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/github-copilot-cli-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/github-copilot-cli-vs-letta.json",
        "title": "GitHub Copilot CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/github-copilot-cli-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/goose-vs-harnessrouter.json",
        "title": "goose vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/goose-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/goose-vs-letta.json",
        "title": "goose vs Letta",
        "url": "https://www.anchorterminal.com/compare/goose-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harness2-vs-harnessrouter.json",
        "title": "Harness² vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/harness2-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harness2-vs-letta.json",
        "title": "Harness² vs Letta",
        "url": "https://www.anchorterminal.com/compare/harness2-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-jules.json",
        "title": "HarnessRouter vs Jules",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-jules"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-junie.json",
        "title": "HarnessRouter vs Junie CLI",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-junie"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-kilo-code-cli.json",
        "title": "HarnessRouter vs Kilo Code CLI",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-kilo-code-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-kimi-code-cli.json",
        "title": "HarnessRouter vs Kimi Code CLI",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-kimi-code-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-kiro-cli.json",
        "title": "HarnessRouter vs Kiro CLI",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-kiro-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-mini-swe-agent.json",
        "title": "HarnessRouter vs mini-swe-agent",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-mini-swe-agent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-minimax-code.json",
        "title": "HarnessRouter vs MiniMax Code",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-minimax-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-mistral-vibe-cli.json",
        "title": "HarnessRouter vs Mistral Vibe CLI",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-mistral-vibe-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-muse-code.json",
        "title": "HarnessRouter vs Muse Code",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-muse-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-openai-agents-api.json",
        "title": "HarnessRouter vs OpenAI Agents API",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-openai-agents-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-openai-codex.json",
        "title": "HarnessRouter vs OpenAI Codex",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-openai-codex"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-opencode.json",
        "title": "HarnessRouter vs OpenCode",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-opencode"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-openhands.json",
        "title": "HarnessRouter vs OpenHands",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-openhands"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-openmausbot.json",
        "title": "HarnessRouter vs OpenMausBot",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-openmausbot"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-orca.json",
        "title": "HarnessRouter vs Orca",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-orca"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-paseo.json",
        "title": "HarnessRouter vs Paseo",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-paseo"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-prime-agent.json",
        "title": "HarnessRouter vs Prime Agent",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-prime-agent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-qoder-cli.json",
        "title": "HarnessRouter vs Qoder CLI",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-qoder-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-qwen-code.json",
        "title": "HarnessRouter vs Qwen Code",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-qwen-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-reflection-mirror.json",
        "title": "HarnessRouter vs Mirror CLI",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-reflection-mirror"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-rovo-dev-cli.json",
        "title": "HarnessRouter vs Rovo Dev CLI",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-rovo-dev-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-sculptor.json",
        "title": "HarnessRouter vs Sculptor",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-sculptor"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-t3-code.json",
        "title": "HarnessRouter vs T3 Code",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-t3-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-traycer.json",
        "title": "HarnessRouter vs Traycer",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-traycer"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-unstoppable.json",
        "title": "HarnessRouter vs Unstoppable",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-unstoppable"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-verdent.json",
        "title": "HarnessRouter vs Verdent",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-verdent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-vibe-trading.json",
        "title": "HarnessRouter vs Vibe-Trading",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-vibe-trading"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-warp.json",
        "title": "HarnessRouter vs Warp (Warp Agent CLI and the Oz Agent API)",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-warp"
      },
      {
        "json": "https://www.anchorterminal.com/compare/jules-vs-letta.json",
        "title": "Jules vs Letta",
        "url": "https://www.anchorterminal.com/compare/jules-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/junie-vs-letta.json",
        "title": "Junie CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/junie-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/kilo-code-cli-vs-letta.json",
        "title": "Kilo Code CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/kilo-code-cli-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/kimi-code-cli-vs-letta.json",
        "title": "Kimi Code CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/kimi-code-cli-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/kiro-cli-vs-letta.json",
        "title": "Kiro CLI vs Letta",
        "url": "https://www.anchorterminal.com/compare/kiro-cli-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-mini-swe-agent.json",
        "title": "Letta vs mini-swe-agent",
        "url": "https://www.anchorterminal.com/compare/letta-vs-mini-swe-agent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-minimax-code.json",
        "title": "Letta vs MiniMax Code",
        "url": "https://www.anchorterminal.com/compare/letta-vs-minimax-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-mistral-vibe-cli.json",
        "title": "Letta vs Mistral Vibe CLI",
        "url": "https://www.anchorterminal.com/compare/letta-vs-mistral-vibe-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-muse-code.json",
        "title": "Letta vs Muse Code",
        "url": "https://www.anchorterminal.com/compare/letta-vs-muse-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-openai-agents-api.json",
        "title": "Letta vs OpenAI Agents API",
        "url": "https://www.anchorterminal.com/compare/letta-vs-openai-agents-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-openai-codex.json",
        "title": "Letta vs OpenAI Codex",
        "url": "https://www.anchorterminal.com/compare/letta-vs-openai-codex"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-opencode.json",
        "title": "Letta vs OpenCode",
        "url": "https://www.anchorterminal.com/compare/letta-vs-opencode"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-openhands.json",
        "title": "Letta vs OpenHands",
        "url": "https://www.anchorterminal.com/compare/letta-vs-openhands"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-openmausbot.json",
        "title": "Letta vs OpenMausBot",
        "url": "https://www.anchorterminal.com/compare/letta-vs-openmausbot"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-orca.json",
        "title": "Letta vs Orca",
        "url": "https://www.anchorterminal.com/compare/letta-vs-orca"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-paseo.json",
        "title": "Letta vs Paseo",
        "url": "https://www.anchorterminal.com/compare/letta-vs-paseo"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-prime-agent.json",
        "title": "Letta vs Prime Agent",
        "url": "https://www.anchorterminal.com/compare/letta-vs-prime-agent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-qoder-cli.json",
        "title": "Letta vs Qoder CLI",
        "url": "https://www.anchorterminal.com/compare/letta-vs-qoder-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-qwen-code.json",
        "title": "Letta vs Qwen Code",
        "url": "https://www.anchorterminal.com/compare/letta-vs-qwen-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-reflection-mirror.json",
        "title": "Letta vs Mirror CLI",
        "url": "https://www.anchorterminal.com/compare/letta-vs-reflection-mirror"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-rovo-dev-cli.json",
        "title": "Letta vs Rovo Dev CLI",
        "url": "https://www.anchorterminal.com/compare/letta-vs-rovo-dev-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-sculptor.json",
        "title": "Letta vs Sculptor",
        "url": "https://www.anchorterminal.com/compare/letta-vs-sculptor"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-t3-code.json",
        "title": "Letta vs T3 Code",
        "url": "https://www.anchorterminal.com/compare/letta-vs-t3-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-traycer.json",
        "title": "Letta vs Traycer",
        "url": "https://www.anchorterminal.com/compare/letta-vs-traycer"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-unstoppable.json",
        "title": "Letta vs Unstoppable",
        "url": "https://www.anchorterminal.com/compare/letta-vs-unstoppable"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-verdent.json",
        "title": "Letta vs Verdent",
        "url": "https://www.anchorterminal.com/compare/letta-vs-verdent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-vibe-trading.json",
        "title": "Letta vs Vibe-Trading",
        "url": "https://www.anchorterminal.com/compare/letta-vs-vibe-trading"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-warp.json",
        "title": "Letta vs Warp (Warp Agent CLI and the Oz Agent API)",
        "url": "https://www.anchorterminal.com/compare/letta-vs-warp"
      },
      {
        "json": "https://www.anchorterminal.com/compare/clawboo-vs-harnessrouter.json",
        "title": "Clawboo vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/clawboo-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/clawboo-vs-letta.json",
        "title": "Clawboo vs Letta",
        "url": "https://www.anchorterminal.com/compare/clawboo-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cli-manager-vs-harnessrouter.json",
        "title": "CLI Manager vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/cli-manager-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cli-manager-vs-letta.json",
        "title": "CLI Manager vs Letta",
        "url": "https://www.anchorterminal.com/compare/cli-manager-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harness-autonomous-vs-harnessrouter.json",
        "title": "Harness vs HarnessRouter",
        "url": "https://www.anchorterminal.com/compare/harness-autonomous-vs-harnessrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harness-autonomous-vs-letta.json",
        "title": "Harness vs Letta",
        "url": "https://www.anchorterminal.com/compare/harness-autonomous-vs-letta"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-paperclip.json",
        "title": "HarnessRouter vs Paperclip",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-paperclip"
      },
      {
        "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-parallax-agents.json",
        "title": "HarnessRouter vs Parallax",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-parallax-agents"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-paperclip.json",
        "title": "Letta vs Paperclip",
        "url": "https://www.anchorterminal.com/compare/letta-vs-paperclip"
      },
      {
        "json": "https://www.anchorterminal.com/compare/letta-vs-parallax-agents.json",
        "title": "Letta vs Parallax",
        "url": "https://www.anchorterminal.com/compare/letta-vs-parallax-agents"
      }
    ],
    "panel": null,
    "scores": [
      {
        "by": 23,
        "edge": "letta",
        "harnessrouter": 35,
        "key": "reliability",
        "letta": 58,
        "name": "Reliability",
        "weight": 16
      },
      {
        "key": "performance",
        "name": "Performance",
        "pending": true,
        "weight": 10
      },
      {
        "by": 13,
        "edge": "harnessrouter",
        "harnessrouter": 83,
        "key": "schema",
        "letta": 70,
        "name": "Schema \u0026 documentation",
        "weight": 13
      },
      {
        "by": 6,
        "edge": "harnessrouter",
        "harnessrouter": 73,
        "key": "ergonomics",
        "letta": 67,
        "name": "Agent ergonomics",
        "weight": 13
      },
      {
        "by": 25,
        "edge": "harnessrouter",
        "harnessrouter": 60,
        "key": "security",
        "letta": 35,
        "name": "Security \u0026 auth",
        "weight": 14
      },
      {
        "by": 35,
        "edge": "letta",
        "harnessrouter": 25,
        "key": "payments",
        "letta": 60,
        "name": "Payments \u0026 pricing",
        "weight": 10
      },
      {
        "key": "tasks",
        "name": "Task success",
        "pending": true,
        "weight": 10
      },
      {
        "by": 13,
        "edge": "letta",
        "harnessrouter": 72,
        "key": "maintenance",
        "letta": 85,
        "name": "Maintenance \u0026 community",
        "weight": 7
      },
      {
        "by": 18,
        "edge": "harnessrouter",
        "harnessrouter": 73,
        "key": "transparency",
        "letta": 55,
        "name": "Transparency \u0026 trust",
        "weight": 7
      }
    ],
    "summary": "Letta scores 59.7 (C) on agent readiness against HarnessRouter's 47.7 (D), and leads in 3 of 7 scored categories. HarnessRouter leads on schema \u0026 documentation, agent ergonomics, security \u0026 auth and transparency \u0026 trust. Both do agent harnesses.",
    "tasks": null,
    "tutorials": [],
    "verdicts": {
      "harnessrouter": "A product's server sends a task to a named harness and gets streamed progress, sessions and files back, under a published OpenAPI contract with idempotency keys and a closed set of error codes. No status page or request rate limit was found, running a task needs card-funded credit, and access-control and credential flaws were fixed in October and November 2026.",
      "letta": "Letta's open-source harness gives agents git-tracked memory blocks, skills, subagents and headless JSON runs, with a $0 plan and public per-agent API prices. It starts in the unrestricted permission mode, defaults to Letta Cloud, sends usage telemetry unless LETTA_CODE_TELEM=0 is set, and the V1 API server the comparisons describe is retired."
    }
  },
  "kind": "anchor.page",
  "links": {
    "api": "https://www.anchorterminal.com/api/v1/index.json",
    "html": "https://www.anchorterminal.com/compare/harnessrouter-vs-letta",
    "json": "https://www.anchorterminal.com/compare/harnessrouter-vs-letta.json",
    "llms": "https://www.anchorterminal.com/llms.txt",
    "markdown": "https://www.anchorterminal.com/compare/harnessrouter-vs-letta.md",
    "mcp": "https://www.anchorterminal.com/mcp",
    "slim": "https://www.anchorterminal.com/compare/harnessrouter-vs-letta.min.md"
  },
  "markdown": "Letta scores 59.7 (C) on agent readiness against HarnessRouter's 47.7 (D), and leads in 3 of 7 scored categories. HarnessRouter leads on schema \u0026 documentation, agent ergonomics, security \u0026 auth and transparency \u0026 trust. Both do agent harnesses.\n\n- HarnessRouter: grade D, 47.7/100, rank #1144 of 1510. Markdown https://www.anchorterminal.com/tools/harnessrouter.md · JSON https://www.anchorterminal.com/api/v1/tools/harnessrouter.json\n- Letta: grade C, 59.7/100, rank #687 of 1510. Markdown https://www.anchorterminal.com/tools/letta.md · JSON https://www.anchorterminal.com/api/v1/tools/letta.json\n- Best agent harnesses and coding agents: https://www.anchorterminal.com/best/agent-harnesses/index.md\n- All 1500 harnesses comparisons: https://www.anchorterminal.com/compare/agent-harnesses/index.md\n- Best memory layers for AI agents: https://www.anchorterminal.com/best/agent-memory/index.md\n- All 353 memory comparisons: https://www.anchorterminal.com/compare/agent-memory/index.md\n\n## Which one, for what\n\n### HarnessRouter (D)\n\nGood for: A product team that wants to run Codex, Claude Code, Hermes or 27 other harnesses server-side behind one task, session and file contract, and switch between them by changing an ID.\n\nAhead on:\n- Schema \u0026 documentation, 83 against 70\n- Agent ergonomics, 73 against 67\n- Security \u0026 auth, 60 against 35\n- Transparency \u0026 trust, 73 against 55\n\nAlso in its favour:\n- A hosted endpoint, with nothing to install\n\nWatch for: No status page found (status.harnessrouter.ai has no DNS record), and the terms give no service level without a signed Order Form\n\n### Letta (C)\n\nGood for: Long-lived coding agents and assistants that keep memory and identity across sessions and machines.\n\nAhead on:\n- Reliability, 58 against 35\n- Payments \u0026 pricing, 60 against 25\n- Maintenance \u0026 community, 85 against 72\n\nAlso in its favour:\n- Runs on your own machine\n- No incidents deducted, where HarnessRouter loses 11 points for them\n\nWatch for: The default permission mode is `unrestricted`, the renamed `bypassPermissions`, so tool calls aren't confirmed unless the user picks another mode\n\n\n## Why the edge\n\n### Payments \u0026 pricing: Letta +35\n\n- HarnessRouter (25): Published rubric, for the hosted service. No machine payment protocol (0). Per-unit prices without a login, agent work per active minute and model calls at listed provider prices per million tokens (20). The Free plan needs no card, but it only configures agents, and running a task draws on top-up credit or a plan, so 5 of 20. A person signs up in a browser and creates the key in the console (0). 0 + 20 + 5 + 0 = 25. Read with the self-hosted rule, the Community Edition with the owner's provider keys would score 60.\n- Letta (60): No x402, MPP or L402 (0 of 40). Per-unit API prices are public, $0.10 per active agent a month and $0.00015 a second of tool execution, plus plan prices (20). A $0 plan with bring-your-own keys; no card is mentioned (20). The CLI runs locally without signing in (20). Total 60.\n\n### Security \u0026 auth: HarnessRouter +25\n\n- HarnessRouter (60): Hosted reading. Bearer Workspace API keys, revocable at once through the API, held to one workspace or reaching the organisation, with harness-bound calibration credentials. No OAuth, per-endpoint scopes or expiry found (20 of 30). Least privilege 10 of 20. disabled_tools per configured agent, enforced by the runtime only where GET /v1/bases says hard, and per-turn cost and step caps, with no approval step for actions a harness takes. Prompt injection 10 of 15. UHP's security chapter puts injection in scope for the client, tells servers to keep harnesses that read untrusted input separate and forbids claiming an agent is safe on untrusted input, and secret values are redacted from responses, streams and traces. Operator visibility 10 of 15. A cost breakdown per task on every plan, and the step-by-step trace is beta, included in Scale or $50 a month. Security programme 10 of 20 (was 8). A disclosure policy (v1.0, effective 30 July 2026) with safe harbour and no bounty, SECURITY.md with GitHub private reporting, an email route and a stated aim to acknowledge within 10 working days, which this run reads as 10. GHSA identifiers are cited in public fix commits; no security.txt and no SOC 2 or ISO 27001 found. 20 + 10 + 10 + 10 + 10 = 60.\n- Letta (35): Harness reading of the framework checklist, as for the other harnesses. 30 for what leaves the machine by default, 20 for approvals and sandboxing, 15 for injection posture, 15 for audit and 20 for the security programme. Letta Cloud is the default backend, so agent state and conversations go to Letta's servers, and telemetry is on by default (10 of 30). The default permission mode is `unrestricted`; `standard`, `acceptEdits` and `strict` are opt-in, and cloud sandboxes exist for remote work (4 of 20). No prompt-injection guidance found for fetched pages or channel messages (5 of 15). Conversation search and git history of memory give an operator a record of what the agent saw and changed (10 of 15). SECURITY.md routes reports to support@letta.com and scopes out the retired server; no security.txt, bounty or certification found (6 of 20). Total 35.\n\n### Reliability: Letta +23\n\n- HarnessRouter (35): Hosted reading, for HarnessRouter Cloud at api.harnessrouter.ai, as on 17 October. No status page (status.harnessrouter.ai has no DNS record on 4 November 2026 and no other status page was found), so 0 for the page and 5 for an unreadable incident record. No request rate limit with numbers was found. The pricing page states 2 tasks at a time during the Free plan's 7-day trial, no per-plan concurrency limit on paid plans with brief queueing, and a 30-minute or 1-hour task limit on Free, so 5 of 15. 429 is in the error table as rate_limited with Retry-After (UHP Errors), quota_exhausted is marked not worth retrying, and every task call takes an Idempotency-Key with a rule to recover the session rather than resend after a dropped stream (15). Terms §5.4 still give no service level outside a signed Order Form (0). The task API isn't labelled beta, while tracing and agent memory are (10). 0 + 5 + 5 + 15 + 0 + 10 = 35.\n- Letta (58): Local-software lines, read for the harness. `@letta-ai/letta-code` on npm with Node.js 22.19 or newer, and PyPI wheels for glibc Linux, macOS 14 and Windows x64 with Python 3.9 or newer stated (20). ci.yml, nightly update smoke tests and Telegram live smoke tests exist, but GitHub's API answered with a rate limit, so run results were unread (15 of 25, unchecked). 332 open issues and pull requests, mostly pull requests; recent bug reports such as recall reading the wrong conversation have no reply yet (15 of 25). 398 tags at 0.34.x with release notes on GitHub, no changelog file, and breaking removals such as AgentFile announced in the README (8 of 15). Pre-1.0 (0). Total 58.\n\n### Transparency \u0026 trust: HarnessRouter +18\n\n- HarnessRouter (73): Editorial half. The server, specification, schema and conformance suite are Apache-2.0. The Cloud's own billing and deployment wasn't confirmed to match the open code, and the Agent Skill has a custom licence for some guides (25 of 30). The privacy policy, DPA, subprocessor list and a retention page agree. Customer content isn't used for training without an opt-in, and periods are stated (tasks deleted at once, agents and files after 30 days, backups within 14 days, credentials within 90, free-plan task records 7 days). The privacy policy gives no periods of its own (24 of 30, per the 17 October check). Deprecation 15 of 20 (was 14). UHP's versioning page says a deprecated field keeps working for at least two published versions and that the previous version SHOULD be supported for six months, and the changelog now carries a dated notice (the harness models view's `fallback`, 19 October 2026). The rule is counted in versions, not time, so dated notices give 15. Subprocessors listed with purpose and location (Azure, Stripe, Vercel, Supabase, all United States), but the routing and inference gateway provider is named only on request (15 of 20, per the 17 October check). 25 + 24 + 15 + 15 = 79. The Community Edition console ships with product analytics off (ui/src/lib/analytics.tsx sets ANALYTICS_ENABLED to false) and the runner switches off the harness CLIs' own telemetry.\n- Letta (55): Apache-2.0 (30). The privacy policy has no date, no legal entity and no retention periods, and says hosted message data may train future models (8 of 30). The README and docs mark AgentFile, the Electron app and the V1 server as deprecated or retired, without dated notice periods (12 of 20). Telemetry is described in the privacy policy only as basic and opt-out when supported; the LETTA_CODE_TELEM=0 switch appears only in the source (5 of 20). Total 55.\n\n### Schema \u0026 documentation: HarnessRouter +13\n\n- HarnessRouter (83): API reading. UHP's OpenAPI 3.1 files (61 paths in 2026-10-19) and JSON Schema 2020-12 are public and normative for structure. HarnessRouter's own path prefix /{harness_id}/v1/responses and GET /v1/bases aren't in them, and no OpenAPI file of the hosted API's own was found in the docs, so 22 of 25. llms.txt, llms-full.txt, agents.md, docs.md, pricing.md and harnesses.md (10). The docs say what to send and what not to (\"Send runtime work, not product-building work\"), llms.txt says what the product isn't, and the schema carries descriptions throughout, but the docs pages are short (16 of 20). Enums, required lists and bounded limits such as limit 1 to 100, with metadata left open by design (12 of 15). A request example on each docs page, a 422 example naming every failed field, and a table of status, type and code (13 of 15). Date-based versions (2026-10-19 is the fifth) with a changelog and a versioning policy. Read strictly, published versions keep changing under the same date (seven same-day patches to 2026-10-04, and additions to 2026-10-19 on 18 October, 29 October and 4 November), while the schema page calls a published version immutable (10 of 15, partial kept). The conformance page and the suite's README now agree on 101 checks. 22 + 10 + 16 + 12 + 13 + 10 = 83.\n- Letta (70): Harness reading. docs.letta.com serves llms.txt and a Markdown version of every page, with an `applies_to` block saying which backend and interface each page covers (10). TypeScript types for the Agent SDK and a documented App Server WebSocket protocol, but no JSON Schema or OpenAPI for the harness (15 of 25). Pages say when to use local or cloud backends, subagents and channels (14 of 20). Permission modes and options are typed in the SDK (12 of 15). Example applications and a remote client reference (11 of 15). Releases most days but no changelog file (8 of 15). Total 70.\n\n### Maintenance \u0026 community: Letta +13\n\n- HarnessRouter (72): Open-source reading of the repository behind the hosted service. Last tag v0.38.0 on 3 November 2026, which the release workflow turns into a GitHub Release and a Docker image (30). 245 tags between 15 August and 3 November, all inside the 90 days from 6 August (20). GitHub's issue pages and API refused this session, so open issues and reply times are unchecked. Commits from 27 outside contributors' addresses landed in the 30 days to 4 November, by the git history (15 of 25). No official SDK and no MCP server to register (0). A tests workflow runs every suite on each pull request and push to main, with a release workflow and a Docker image, but whether the default branch passes is unchecked (7 of 10). 30 + 20 + 15 + 0 + 7 = 72.\n- Letta (85): v0.34.42 on 6 November 2026 (30). Dozens of releases in 90 days (20). Pull requests are merged daily; recent issues from users have few replies (15 of 25). npm and PyPI packages and the Agent SDK track the releases (12 of 15). Lock files, CI and nightly smoke tests (8 of 10). Total 85.\n\n## Score by category\n\n| Category | Weight | HarnessRouter | Letta | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 35 | 58 | Letta +23 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 83 | 70 | HarnessRouter +13 |\n| Agent ergonomics | 13% (16.2 this run) | 73 | 67 | HarnessRouter +6 |\n| Security \u0026 auth | 14% (17.5 this run) | 60 | 35 | HarnessRouter +25 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 25 | 60 | Letta +35 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 72 | 85 | Letta +13 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 73 | 55 | HarnessRouter +18 |\n| Negative events | ≤15 | -11 | 0 | |\n| **Total** | | **47.7 · D** | **59.7 · C** | |\n\n## Facts side by side\n\n| Fact | HarnessRouter | Letta |\n| --- | --- | --- |\n| Kind | Agent harness | Agent harness |\n| Vendor | HarnessRouter (Lumentree Corporation) | Letta |\n| Hosted endpoint | `https://api.harnessrouter.ai` | no (local only) |\n| Transports | HTTP | stdio |\n| Auth | API key | OAuth or key |\n| Pricing | Pay per use | Freemium |\n| x402 | no | no |\n| Licence | Apache-2.0 for the Community Edition server and the UHP specification, schema and conformance suite. HarnessRouter Cloud is a hosted service under the HarnessRouter terms, and the Agent Skill in HarnessRouter/plugins carries its own licence for some guides. | Apache-2.0 |\n| Tools exposed | 0 | none |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| Last release | 2026-11-03 | 2026-11-06 |\n| Terms last updated | no date given | no date given |\n| Privacy policy last updated | 2026-07-30 | no date given |\n| Customer content may train models | yes, with an opt-out | not found in the text |\n| Terms restrict automated access | yes | not found in the text |\n| Terms restrict benchmarking | not found in the text | not found in the text |\n| Terms or service can change without notice | not found in the text | not found in the text |\n| Arbitration or class-action waiver | yes | yes |\n| Popularity | 4.1k stars | 3.8k stars, 86k npm/wk, 2.2k PyPI/wk |\n| Agent reviews | 2.5/5 (4) | none |\n\n## How the scores have moved\n\n### HarnessRouter\n\n- -5.6 on 4 November 2026: correction, negative event\n- -0.1 on 30 October 2026: checklist\n- +0.2 on 27 October 2026: checklist\n\n### Letta\n\nNo score change since it was listed.\n\n## Verdicts\n\n**HarnessRouter.** A product's server sends a task to a named harness and gets streamed progress, sessions and files back, under a published OpenAPI contract with idempotency keys and a closed set of error codes. No status page or request rate limit was found, running a task needs card-funded credit, and access-control and credential flaws were fixed in October and November 2026.\n\n**Letta.** Letta's open-source harness gives agents git-tracked memory blocks, skills, subagents and headless JSON runs, with a $0 plan and public per-agent API prices. It starts in the unrestricted permission mode, defaults to Letta Cloud, sends usage telemetry unless LETTA_CODE_TELEM=0 is set, and the V1 API server the comparisons describe is retired.\n\n## Before you call either\n\n### HarnessRouter\n\n1. Name the harness yourself. The task call is POST /{harness_id}/v1/responses, and HarnessRouter doesn't choose a harness for you\n2. Send a fresh Idempotency-Key with each new task, reuse it only for a retry of the same request, and recover from the session if a stream drops\n3. Call cancel to stop work. Closing the SSE connection leaves the agent running and billing\n4. Keep the Workspace API key on the server. The docs forbid calling the API from a browser with it\n5. Check each tool's enforcement in GET /v1/bases. On bases marked instruction, disabled_tools is a request to the model, not a block\n\n### Letta\n\n1. Start headless runs with an explicit permission mode such as `standard` or `strict`; the default auto-approves tools\n2. Pass `--backend local` for work that must stay on the machine, since Letta Cloud is the default\n3. Set LETTA_CODE_TELEM=0 in unattended runs if usage events must not be sent\n4. Use `letta -p --output-format json` for scripted runs and parse the JSON, not the terminal output\n5. Don't plan on the retired V1 REST server or `.af` AgentFile import; both are gone\n\n## Questions\n\n### Which is better for AI agents, HarnessRouter or Letta?\n\nLetta scores 59.7 (C) on agent readiness against HarnessRouter's 47.7 (D), and leads in 3 of 7 scored categories. HarnessRouter leads on schema \u0026 documentation, agent ergonomics, security \u0026 auth and transparency \u0026 trust.\n\n### Are HarnessRouter and Letta open source?\n\nYes. HarnessRouter is open source (Apache-2.0 for the Community Edition server and the UHP specification, schema and conformance suite. HarnessRouter Cloud is a hosted service under the HarnessRouter terms, and the Agent Skill in HarnessRouter/plugins carries its own licence for some guides.). Letta is open source (Apache-2.0).\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/harnessrouter-vs-letta.json, and with the fewest tokens: https://www.anchorterminal.com/compare/harnessrouter-vs-letta.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"harnessrouter\", \"b\": \"letta\"}`. From a terminal: `anchor compare harnessrouter letta`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/harnessrouter.json and https://www.anchorterminal.com/api/v1/tools/letta.json\n\n## Other comparisons with HarnessRouter or Letta\n\n- [Agent Zero vs HarnessRouter](https://www.anchorterminal.com/compare/agent-zero-vs-harnessrouter.md)\n- [Agent Zero vs Letta](https://www.anchorterminal.com/compare/agent-zero-vs-letta.md)\n- [Aider vs HarnessRouter](https://www.anchorterminal.com/compare/aider-vs-harnessrouter.md)\n- [Aider vs Letta](https://www.anchorterminal.com/compare/aider-vs-letta.md)\n- [Amp vs HarnessRouter](https://www.anchorterminal.com/compare/amp-vs-harnessrouter.md)\n- [Amp vs Letta](https://www.anchorterminal.com/compare/amp-vs-letta.md)\n- [Antigravity CLI vs HarnessRouter](https://www.anchorterminal.com/compare/antigravity-cli-vs-harnessrouter.md)\n- [Antigravity CLI vs Letta](https://www.anchorterminal.com/compare/antigravity-cli-vs-letta.md)\n- [Auggie CLI vs HarnessRouter](https://www.anchorterminal.com/compare/auggie-vs-harnessrouter.md)\n- [Auggie CLI vs Letta](https://www.anchorterminal.com/compare/auggie-vs-letta.md)\n- [AXLR vs HarnessRouter](https://www.anchorterminal.com/compare/axlr-vs-harnessrouter.md)\n- [AXLR vs Letta](https://www.anchorterminal.com/compare/axlr-vs-letta.md)\n- [Claude Code vs HarnessRouter](https://www.anchorterminal.com/compare/claude-code-vs-harnessrouter.md)\n- [Claude Code vs Letta](https://www.anchorterminal.com/compare/claude-code-vs-letta.md)\n- [Cline vs HarnessRouter](https://www.anchorterminal.com/compare/cline-vs-harnessrouter.md)\n- [Cline vs Letta](https://www.anchorterminal.com/compare/cline-vs-letta.md)\n- [Conductor vs HarnessRouter](https://www.anchorterminal.com/compare/conductor-vs-harnessrouter.md)\n- [Conductor vs Letta](https://www.anchorterminal.com/compare/conductor-vs-letta.md)\n- [Crush vs HarnessRouter](https://www.anchorterminal.com/compare/crush-vs-harnessrouter.md)\n- [Crush vs Letta](https://www.anchorterminal.com/compare/crush-vs-letta.md)\n- [Cursor CLI vs HarnessRouter](https://www.anchorterminal.com/compare/cursor-cli-vs-harnessrouter.md)\n- [Cursor CLI vs Letta](https://www.anchorterminal.com/compare/cursor-cli-vs-letta.md)\n- [DeepSeek Harness (dsh) vs HarnessRouter](https://www.anchorterminal.com/compare/deepseek-harness-vs-harnessrouter.md)\n- [DeepSeek Harness (dsh) vs Letta](https://www.anchorterminal.com/compare/deepseek-harness-vs-letta.md)\n- [dsh-superagent (DeepSeek) vs HarnessRouter](https://www.anchorterminal.com/compare/deepseek-superagent-vs-harnessrouter.md)\n- [dsh-superagent (DeepSeek) vs Letta](https://www.anchorterminal.com/compare/deepseek-superagent-vs-letta.md)\n- [Devin vs HarnessRouter](https://www.anchorterminal.com/compare/devin-vs-harnessrouter.md)\n- [Devin vs Letta](https://www.anchorterminal.com/compare/devin-vs-letta.md)\n- [Droid CLI vs HarnessRouter](https://www.anchorterminal.com/compare/droid-cli-vs-harnessrouter.md)\n- [Droid CLI vs Letta](https://www.anchorterminal.com/compare/droid-cli-vs-letta.md)\n- [Pi vs HarnessRouter](https://www.anchorterminal.com/compare/earendil-pi-vs-harnessrouter.md)\n- [Pi vs Letta](https://www.anchorterminal.com/compare/earendil-pi-vs-letta.md)\n- [Emdash vs HarnessRouter](https://www.anchorterminal.com/compare/emdash-vs-harnessrouter.md)\n- [Emdash vs Letta](https://www.anchorterminal.com/compare/emdash-vs-letta.md)\n- [Gemini CLI vs HarnessRouter](https://www.anchorterminal.com/compare/gemini-cli-vs-harnessrouter.md)\n- [Gemini CLI vs Letta](https://www.anchorterminal.com/compare/gemini-cli-vs-letta.md)\n- [GitHub Copilot CLI vs HarnessRouter](https://www.anchorterminal.com/compare/github-copilot-cli-vs-harnessrouter.md)\n- [GitHub Copilot CLI vs Letta](https://www.anchorterminal.com/compare/github-copilot-cli-vs-letta.md)\n- [goose vs HarnessRouter](https://www.anchorterminal.com/compare/goose-vs-harnessrouter.md)\n- [goose vs Letta](https://www.anchorterminal.com/compare/goose-vs-letta.md)\n- [Harness² vs HarnessRouter](https://www.anchorterminal.com/compare/harness2-vs-harnessrouter.md)\n- [Harness² vs Letta](https://www.anchorterminal.com/compare/harness2-vs-letta.md)\n- [HarnessRouter vs Jules](https://www.anchorterminal.com/compare/harnessrouter-vs-jules.md)\n- [HarnessRouter vs Junie CLI](https://www.anchorterminal.com/compare/harnessrouter-vs-junie.md)\n- [HarnessRouter vs Kilo Code CLI](https://www.anchorterminal.com/compare/harnessrouter-vs-kilo-code-cli.md)\n- [HarnessRouter vs Kimi Code CLI](https://www.anchorterminal.com/compare/harnessrouter-vs-kimi-code-cli.md)\n- [HarnessRouter vs Kiro CLI](https://www.anchorterminal.com/compare/harnessrouter-vs-kiro-cli.md)\n- [HarnessRouter vs mini-swe-agent](https://www.anchorterminal.com/compare/harnessrouter-vs-mini-swe-agent.md)\n- [HarnessRouter vs MiniMax Code](https://www.anchorterminal.com/compare/harnessrouter-vs-minimax-code.md)\n- [HarnessRouter vs Mistral Vibe CLI](https://www.anchorterminal.com/compare/harnessrouter-vs-mistral-vibe-cli.md)\n- [HarnessRouter vs Muse Code](https://www.anchorterminal.com/compare/harnessrouter-vs-muse-code.md)\n- [HarnessRouter vs OpenAI Agents API](https://www.anchorterminal.com/compare/harnessrouter-vs-openai-agents-api.md)\n- [HarnessRouter vs OpenAI Codex](https://www.anchorterminal.com/compare/harnessrouter-vs-openai-codex.md)\n- [HarnessRouter vs OpenCode](https://www.anchorterminal.com/compare/harnessrouter-vs-opencode.md)\n- [HarnessRouter vs OpenHands](https://www.anchorterminal.com/compare/harnessrouter-vs-openhands.md)\n- [HarnessRouter vs OpenMausBot](https://www.anchorterminal.com/compare/harnessrouter-vs-openmausbot.md)\n- [HarnessRouter vs Orca](https://www.anchorterminal.com/compare/harnessrouter-vs-orca.md)\n- [HarnessRouter vs 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CLI](https://www.anchorterminal.com/compare/letta-vs-qoder-cli.md)\n- [Letta vs Qwen Code](https://www.anchorterminal.com/compare/letta-vs-qwen-code.md)\n- [Letta vs Mirror CLI](https://www.anchorterminal.com/compare/letta-vs-reflection-mirror.md)\n- [Letta vs Rovo Dev CLI](https://www.anchorterminal.com/compare/letta-vs-rovo-dev-cli.md)\n- [Letta vs Sculptor](https://www.anchorterminal.com/compare/letta-vs-sculptor.md)\n- [Letta vs T3 Code](https://www.anchorterminal.com/compare/letta-vs-t3-code.md)\n- [Letta vs Traycer](https://www.anchorterminal.com/compare/letta-vs-traycer.md)\n- [Letta vs Unstoppable](https://www.anchorterminal.com/compare/letta-vs-unstoppable.md)\n- [Letta vs Verdent](https://www.anchorterminal.com/compare/letta-vs-verdent.md)\n- [Letta vs Vibe-Trading](https://www.anchorterminal.com/compare/letta-vs-vibe-trading.md)\n- [Letta vs Warp (Warp Agent CLI and the Oz Agent API)](https://www.anchorterminal.com/compare/letta-vs-warp.md)\n- [Clawboo vs 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