{
  "data": {
    "a": {
      "slug": "axlr",
      "name": "AXLR",
      "vendor": "Underpass AI",
      "vendorUrl": "https://axlr.underpassai.com",
      "kind": "harness",
      "category": "agent-harnesses",
      "summary": "Open-source Go execution engine for agentic work from Underpass AI. A console with work modes and approval cards, an mTLS HTTP, gRPC and MCP service, a JSON worker and a Go library, with KMP memory and MADE procedures over MCP.",
      "url": "https://www.anchorterminal.com/tools/axlr",
      "markdownUrl": "https://www.anchorterminal.com/tools/axlr.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/axlr.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/axlr.json",
      "dns": "axlr.grade.anchorterminal.com",
      "repo": "https://github.com/underpass-ai/AXLR",
      "license": "Apache-2.0, with a NOTICE naming Tirso García Ibáñez as the copyright holder",
      "transports": [],
      "packages": [
        {
          "registry": "go",
          "name": "github.com/underpass-ai/AXLR"
        },
        {
          "registry": "oci",
          "name": "ghcr.io/underpass-ai/axlr"
        },
        {
          "registry": "oci",
          "name": "ghcr.io/underpass-ai/charts/axlr"
        }
      ],
      "auth": "mixed",
      "authNotes": "The console and the one-command `axlr-tui --exec` need a model route, an OpenRouter key (`OPENROUTER_API_KEY` or `credentials.json`, mode 0600), a local OpenAI-compatible server, or an Anthropic Messages or OpenAI Responses key in a `local_models` entry; the JSON worker and the library tests need no model account. The service, `axlr-serve`, requires TLS 1.3 and a client certificate signed by its CA whose SHA-256 fingerprint is mapped in a private principals file to a principal and the roles `session_client`, `approver`, `tool_operator` and `admin`; an unmapped certificate is forbidden, a session belongs to the principal that created it, and authentication never approves a tool by itself. MCP at `/mcp` is stateless and authenticated per request by the same certificate; gRPC uses the TLS peer certificate.",
      "pricing": "free",
      "pricingNotes": "Free and open source under Apache-2.0, with nothing to buy from Underpass AI. You pay your model provider (OpenRouter reports a cost per request, which the console's `/usage` and `max_session_usd` track) or run a local server at no charge; TypeSafe's Jev judge is optional and needs its own key. No hosted AXLR exists (checked 2026-11-01).",
      "priceSummary": "Free · OSS",
      "where": "local",
      "x402": {
        "level": "no",
        "evidence": "No x402, MPP or L402 in the repository, the OpenAPI file or the two sites (checked 2026-11-01). Nothing is sold.",
        "endpoints": []
      },
      "toolCount": null,
      "popularity": {
        "githubStars": 0,
        "npmWeekly": null,
        "pypiWeekly": null,
        "asOf": "2026-11-01"
      },
      "docsUrl": "https://axlr.underpassai.com/docs/",
      "openapi": "https://github.com/underpass-ai/AXLR/blob/main/api/openapi/axlr-v1.yaml",
      "capabilities": [
        "agent.harness",
        "agent.mcp-client",
        "agent.multi-agent"
      ],
      "tags": [
        "open-source",
        "local",
        "self-hosted",
        "free",
        "no-card",
        "go",
        "cli",
        "mcp-client",
        "openapi",
        "grpc",
        "docker",
        "helm",
        "sandbox",
        "approvals",
        "pre-1.0",
        "new"
      ],
      "lastRelease": "2026-10-25",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 70.6,
        "grade": "BB",
        "agentReady": true,
        "rank": 197,
        "ranked": true,
        "rankOf": 1486,
        "categoryRank": 4,
        "methodology": "0.7",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 83,
          "maintenance": 79,
          "payments": 60,
          "reliability": 70,
          "schema": 80,
          "security": 62,
          "transparency": 55
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-11-01"
        },
        "negative": 0,
        "verdict": "A pre-1.0 Go harness with an unusually complete service contract, mutual TLS with principal roles, required idempotency keys, a policy, budget and sandbox per execution, and a result object a program can read. The console's defaults after setup are autonomy on and no sandbox, the project has one maintainer and no outside users yet, and releases carry no notes.",
        "bestFor": "A program or bot that needs one governed execution at a time, with a policy, a budget, a sandbox profile and correlation ids it sets itself and a result object it reads back, on a machine it controls, with the model on OpenRouter, a local server or a native Anthropic or OpenAI key.",
        "strengths": [
          "mTLS HTTP, gRPC and MCP service with four principal roles, `Idempotency-Key` required on turns, approvals and direct calls, and `expected_revision` on decisions",
          "A policy (observe, propose, act-with-approval, act-within-policy), a budget in seconds, requests, tool calls and dollars, and a bubblewrap or container sandbox with an enforced egress allow list, each per execution",
          "`axlr-tui --exec --json` runs one task headless and ends with a result object; exit 0 done, 3 waiting for a decision, 1 error",
          "OpenRouter, local OpenAI-compatible servers (llama.cpp, vLLM, Ollama, LM Studio), and the Anthropic Messages and OpenAI Responses APIs spoken directly",
          "21 releases in October 2026 from a workflow that tests on six native runners and refuses to republish different bytes, with a `.sha256` beside every archive"
        ],
        "weaknesses": [
          "The setup assistant turns autonomy on and leaves the exec sandbox off, so after setup the model's commands run with the person's rights, bar the destructive list",
          "Pre-1.0 with one maintainer, 0 stars and 10 open issues, all the founder's own trackers; releases have empty notes and there is no changelog",
          "The service needs KMP and MADE as remote gRPC services, a client CA and a principals file before a first session, and has no work modes, plugins or forged-tool setting yet",
          "No SECURITY.md, security.txt, advisories or disclosure route; the legal entity is not yet incorporated and no terms or privacy policy exist",
          "No llms.txt, and the Go library is the only SDK; the catalog registry answers every non-AXLR client with 403"
        ],
        "agentNotes": [
          "Before the first prompt, set `approvals.autonomous` to false or run with `--approve none`, and turn `exec_sandbox.mode` to `auto` or `required` on Linux; after setup both default the other way",
          "Drive a run with `axlr-tui --exec --json --policy \u003cfile\u003e --budget \u003cfile\u003e --sandbox \u003cfile\u003e` and read only the last `result` line; exit 3 means a call waits for `--decide approve|deny` with `--session \u003cid\u003e`",
          "On the service, send `Idempotency-Key` (16 to 128 safe ASCII characters) on every turn, approval and direct call, and pass the session's `expected_revision`; a reused key with a different body answers 409",
          "A local model must return native tool calls (llama.cpp with `--jinja`, vLLM with `--enable-auto-tool-choice`); set `context_tokens` on the entry and `OLLAMA_CONTEXT_LENGTH` for Ollama",
          "Leave `TYPESAFE_API_KEY` unset unless you want the setup assistant to switch Jev on, which sends requests and final answers to TypeSafe"
        ],
        "metrics": {
          "kind": "local",
          "measured": false
        },
        "reviewCount": 0,
        "avgRating": 0,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "BB",
            "methodology": "0.7",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 70.6
          }
        ],
        "editorialScores": {
          "ergonomics": 83,
          "maintenance": 79,
          "payments": 60,
          "reliability": 70,
          "schema": 80,
          "security": 62,
          "transparency": 68
        },
        "provenanceScore": 42,
        "checked": {
          "categories": {
            "ergonomics": "2026-11-01",
            "maintenance": "2026-11-01",
            "payments": "2026-11-01",
            "reliability": "2026-11-01",
            "schema": "2026-11-01",
            "security": "2026-11-01",
            "transparency": "2026-11-01"
          },
          "last": "2026-11-01",
          "oldest": "2026-11-01",
          "stale": false,
          "staleAfterDays": 90
        }
      },
      "connect": {
        "install": "V=v0.15.0; OS=linux; ARCH=amd64; curl -fsSLO https://github.com/underpass-ai/AXLR/releases/download/$V/axlr-$V-$OS-$ARCH.tar.gz{,.sha256} \u0026\u0026 sha256sum -c axlr-$V-$OS-$ARCH.tar.gz.sha256 \u0026\u0026 tar xzf axlr-$V-$OS-$ARCH.tar.gz -C ~/.local/bin axlr axlr-tui axlr-serve   # or build from source with Go 1.26",
        "headless": {
          "command": "axlr-tui --root \"$PWD\" --exec \"$TASK\" --json --approve none --policy policy.json --budget budget.json --sandbox sandbox.json",
          "decide": "axlr-tui --session \u003cid\u003e --decide approve --json",
          "env": {
            "OPENROUTER_API_KEY": "\u003ckey\u003e"
          }
        }
      },
      "letme": {
        "capability": "https://letme.dev/agent.harness",
        "tool": "https://letme.dev/axlr"
      },
      "area": "frameworks",
      "provenance": {
        "legalEntity": "",
        "domain": "underpassai.com",
        "domainRegistered": "2025-08-10",
        "endpointOnVendorDomain": null,
        "terms": "",
        "privacy": "",
        "statusPage": "",
        "changelog": "https://github.com/underpass-ai/AXLR/releases",
        "securityTxt": "none",
        "checked": "2026-11-01",
        "notes": [
          "No legal entity exists yet. underpassai.com's footer says Underpass AI is a startup project created by Tirso García Ibáñez and preparing incorporation as a Spanish limited liability company, that the technical assets are founder-owned and intended to be assigned to the company after incorporation, and that licence terms are in each repository's LICENSE and NOTICE. The NOTICE names Tirso García Ibáñez as copyright holder. Recorded as absent with that explanation.",
          "No terms of service or privacy policy on underpassai.com (sitemap lists the home page and one article) or axlr.underpassai.com. For local software the docs' 'Where data goes' and 'Diagnostics and privacy' sections stand in.",
          "RDAP for underpassai.com gives registration on 2025-08-10 with Route 53 nameservers. The GitHub organisation underpass-ai was created on 2025-08-09, location Spain, 16 public repositories. The AXLR repository was created on 2026-09-29; the first tag and release, v0.1.0, is dated 2026-10-04, which is firstReleased.",
          "https://underpassai.com/.well-known/security.txt and https://axlr.underpassai.com/.well-known/security.txt answer 404; the repository has no SECURITY.md. No status page (local software). The changelog is the GitHub releases list, whose entries carry no notes.",
          "robots.txt on underpassai.com and axlr.underpassai.com allow everything. registry.underpassai.com answers every path, robots.txt included, with 403 'forbidden: client is not AXLR', so nothing was read from it after that reply.",
          "The founder's LinkedIn URL is linked from underpassai.com and was not visited."
        ],
        "score": 42
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/axlr.json",
      "live": {
        "slug": "axlr",
        "versions": [
          {
            "registry": "github",
            "name": "underpass-ai/AXLR",
            "version": "v0.15.0",
            "released": "2026-10-25",
            "seenAt": "2026-11-06T23:08:48.738681832Z"
          }
        ],
        "githubStars": 0,
        "securityTxt": {
          "url": "https://underpassai.com/.well-known/security.txt",
          "state": "none",
          "checkedAt": "2026-11-07T16:00:48.673912463Z"
        },
        "github": {
          "repo": "underpass-ai/axlr",
          "checkedAt": "2026-11-02T08:24:06.082445818Z",
          "stars": 0,
          "archived": false,
          "issuesEnabled": true,
          "pushedAt": "2026-11-01T12:37:37Z",
          "openIssues": 10,
          "openPRs": 0,
          "issuesOpened90d": 17,
          "issuesClosed90d": 7,
          "prsMerged90d": 170,
          "ci": {
            "branch": "main",
            "runs": 50,
            "success": 47,
            "failure": 3,
            "other": 0,
            "latest": "success",
            "latestAt": "2026-11-01T12:40:55Z"
          },
          "replies": {
            "sampled": 17,
            "unanswered": 10,
            "medianDays": 0.3
          }
        },
        "updatedAt": "2026-11-07T16:00:48.673912463Z"
      }
    },
    "answer": "AXLR scores 70.6 (BB) on agent readiness against Letta's 59.7 (C), and leads in 4 of 7 scored categories. Letta leads on maintenance \u0026 community.",
    "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": 684,
        "ranked": true,
        "rankOf": 1486,
        "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": 27,
        "category": "security",
        "leads": "axlr",
        "name": "Security \u0026 auth",
        "reasons": {
          "a": "Harness reading of the framework checklist, as for the other four harnesses. 30 for what leaves the machine by default, 20 for approvals and sandboxing, 15 for prompt-injection posture, 15 for audit and 20 for the security programme. No product telemetry in the console source (the outbound hosts are openrouter.ai, api.anthropic.com, api.openai.com, a configured local server, api.github.com and github.com for engine downloads, and registry.underpassai.com for the signed catalog index) or in the docs; payload capture is off by default since 9 October 2026, traces omit prompts and credentials, model keys are never given to commands or plugins, and Jev sends requests and answers to TypeSafe only when on, which the setup assistant does when `TYPESAFE_API_KEY` is set, with a notice on stderr (27). Approval cards, a destructive list that always asks, four work modes, a policy level per execution, a bubblewrap or container sandbox with an enforced egress allow list, and a service that approves nothing but reads. Against that, the setup assistant writes `autonomous: true`, `exec_sandbox` is off by default, forged tools run with the person's rights, and the README says the console and worker are not sandboxes (13). Forged tools are refused when a file changes since the forge, a policy forbids calls outside the model, and the docs say MCP tools keep their own side effects, but no prompt-injection guidance was found and MCP results reach the model unmarked (6). The service keeps an event journal, audit records, a receipt with the SHA-256 of every call's arguments and outcome, and correlation ids on every event; the console keeps session records, a redacted app log and `/session` (14). No SECURITY.md, no security.txt on either host, no advisories, no bug bounty; release checksums and a minisign-signed catalog are integrity, not a programme (2). 27+13+6+14+2 = 62.",
          "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": 62,
          "b": 35
        }
      },
      {
        "by": 16,
        "category": "ergonomics",
        "leads": "axlr",
        "name": "Agent ergonomics",
        "reasons": {
          "a": "Harness reading of the framework line, scored on what a program driving it has to supply. Six local tools plus the host's bookkeeping tools; work modes and an execution policy hide the tools a run may not use, `axlr_catalog` searches the catalog instead of loading it, forged tools keep the request prefix for the prompt cache, and a context cap of 75,000 prompt tokens opens a successor session (20). `local_read`, `local_search` and `local_list` page with `offset`, `next_offset` and `max_bytes`; `StreamEvents` takes `after`, `max_events` (1 to 256) and `wait_ms`; a budget per execution in seconds, requests, tool calls and dollars; 32 tool calls a turn and `max_session_usd` (20). The `--exec` run ends in one `result` line with a status, the pending call, every call's outcome and the usage, and exits 0, 3 or 1; service errors carry codes an agent can act on; a budget stop says which limit (`budget: requests 20 reached`) and leaves the session resumable (16). `Idempotency-Key` on every turn, approval and direct call with cross-transport replay, `expected_revision` on decisions, `expected_sha256` on worker writes, and an interrupted effectful call left `uncertain` for an operator rather than retried (19). One command runs a task, but the first launch needs an OpenRouter key or a local server, the service needs a CA, a principals file and remote KMP and MADE before a first session, and the only SDK is the Go library (8). 20+20+16+19+8 = 83.",
          "b": "Harness reading. Toolsets switch with `/model`, skills load per agent, and subagents run in the background (18 of 25). Context is managed through memory blocks, reflection and dreaming (12 of 20). `letta -p --output-format json` for scripted runs and an App Server for programmatic control (12 of 20). Conversations resume by agent and conversation id, and memory is git-tracked so changes can be reverted (15 of 20). Runs with no account on the local backend, with one SDK language, TypeScript (10 of 15). Total 67."
        },
        "scores": {
          "a": 83,
          "b": 67
        }
      },
      {
        "by": 12,
        "category": "reliability",
        "leads": "axlr",
        "name": "Reliability",
        "reasons": {
          "a": "Read as a local package, as claude-code, goose, opencode and openhands were. Release archives for Linux, macOS and Windows on amd64 and arm64 with a `.sha256` beside each, a GHCR image, an OCI Helm chart and source builds with Go 1.26, all stated in the docs; no Homebrew, npm or apt route (20). CI on main runs vet, race tests and a coverage gate above 80 per cent for both modules, with the sandbox tests required under bubblewrap, and the last ten runs on main to 1 November 2026 all passed; the release workflow tests on six native runners (25). 10 open issues, all opened by the founder on 19 and 21 October 2026 as trackers for service work (work modes, plugins, the sandbox setting, cost limits), none from an outside user and none a crash report, 0 open pull requests and about 100 merged; with 0 stars there is nobody else to report, so the handling of outside reports is untested (20). Tags are semver 0.x and the docs date each behaviour change inline (\"until 14 October 2026…\"), but the 21 releases have empty notes, there is no CHANGELOG.md, and the product contract records one retirement (the seven 1.0 skill definitions on 5 October 2026) without a notice period (5). Pre-1.0, which the README calls an evolving project (0). 20+25+20+5+0 = 70.",
          "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": 70,
          "b": 58
        }
      },
      {
        "by": 10,
        "category": "schema",
        "leads": "axlr",
        "name": "Schema \u0026 documentation",
        "reasons": {
          "a": "An OpenAPI 3.1 file for the service (15 paths, 23 schemas, `mutualTLS` security scheme, `additionalProperties: false` on request bodies), a checked proto for the gRPC service, and the 19 MCP tools built from the same shared schemas (25). No llms.txt on either site (404), and the docs site renders HTML; the Markdown sources are in the repository (5). The product contract tables what each of the four interfaces can and cannot do, the work-mode table states each mode's purpose and tool policy, the transport parity ledger names every verb's arguments and behaviour, and `axlr_tools` tells the model to look for a tool before forging one (15). Typed inputs throughout, `Idempotency-Key` 16 to 128 safe ASCII characters, `expected_revision` a positive integer, policy levels, sandbox profiles and egress values enumerated, budgets as four integers, and the service rejects unknown fields, invalid types and bodies over 4 MiB (14). Examples in every guide, an error shape of `code`, `message` and `request_id`, named codes (`409 idempotency_conflict`, `400 invalid_cursor`, `422 invalid_policy`, `invalid_budget`, `sandbox_unavailable`, `not_ready`, `invalid_id`), a gRPC status mapping, and the worker's five statuses and three exit codes; no single error reference page (14). `/v1` routes and an OpenAPI version of 0.1.0 against a 0.15.0 release, and no changelog beyond the dated notes inside the docs (7). 25+5+15+14+14+7 = 80.",
          "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": 80,
          "b": 70
        }
      },
      {
        "by": 6,
        "category": "maintenance",
        "leads": "letta",
        "name": "Maintenance \u0026 community",
        "reasons": {
          "a": "v0.15.0 on 2026-10-25, with commits on main to 2026-11-01 (30). 21 releases between 4 and 25 October 2026 (20). One maintainer (368 of 399 commits, the rest by two agent accounts), 10 open issues that are his own trackers with no comments, about 100 merged pull requests and no outside report to measure a reply against (15). Not in the MCP registry; the Go module and a proto to generate clients from are the only client code, beside the GHCR image and Helm chart (5). Go 1.26 toolchain pinned, release actions pinned by commit SHA, a go-licenses check that the third-party bundle matches the dependency graph, and CI passing on main (9). 30+20+15+5+9 = 79.",
          "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": 79,
          "b": 85
        }
      }
    ],
    "facts": [
      {
        "a": "Agent harness",
        "b": "Agent harness",
        "name": "Kind"
      },
      {
        "a": "Underpass AI",
        "b": "Letta",
        "name": "Vendor"
      },
      {
        "a": "no (local only)",
        "b": "no (local only)",
        "name": "Hosted endpoint"
      },
      {
        "a": "",
        "b": "stdio",
        "name": "Transports"
      },
      {
        "a": "OAuth or key",
        "b": "OAuth or key",
        "name": "Auth"
      },
      {
        "a": "Free",
        "b": "Freemium",
        "name": "Pricing"
      },
      {
        "a": "no",
        "b": "no",
        "name": "x402"
      },
      {
        "a": "Apache-2.0, with a NOTICE naming Tirso García Ibáñez as the copyright holder",
        "b": "Apache-2.0",
        "name": "Licence"
      },
      {
        "a": "no",
        "b": "no",
        "name": "Read-only variant documented"
      },
      {
        "a": "no",
        "b": "yes",
        "name": "llms.txt"
      },
      {
        "a": "2026-10-25",
        "b": "2026-11-06",
        "name": "Last release"
      },
      {
        "a": "no document linked",
        "b": "no date given",
        "name": "Terms last updated"
      },
      {
        "a": "no document linked",
        "b": "no date given",
        "name": "Privacy policy last updated"
      },
      {
        "a": "not read yet",
        "b": "not found in the text",
        "name": "Customer content may train models"
      },
      {
        "a": "not read yet",
        "b": "not found in the text",
        "name": "Terms restrict automated access"
      },
      {
        "a": "not read yet",
        "b": "not found in the text",
        "name": "Terms restrict benchmarking"
      },
      {
        "a": "not read yet",
        "b": "not found in the text",
        "name": "Terms or service can change without notice"
      },
      {
        "a": "not read yet",
        "b": "yes",
        "name": "Arbitration or class-action waiver"
      },
      {
        "a": "0 stars",
        "b": "3.8k stars, 86k npm/wk, 2.2k PyPI/wk",
        "name": "Popularity"
      }
    ],
    "faq": [
      {
        "answer": "AXLR scores 70.6 (BB) on agent readiness against Letta's 59.7 (C), and leads in 4 of 7 scored categories. Letta leads on maintenance \u0026 community.",
        "question": "Which is better for AI agents, AXLR or Letta?"
      },
      {
        "answer": "Yes. AXLR is open source (Apache-2.0, with a NOTICE naming Tirso García Ibáñez as the copyright holder). Letta is open source (Apache-2.0).",
        "question": "Are AXLR and Letta open source?"
      }
    ],
    "goodFor": [
      {
        "aheadOn": [
          "Reliability, 70 against 58",
          "Schema \u0026 documentation, 80 against 70",
          "Agent ergonomics, 83 against 67",
          "Security \u0026 auth, 62 against 35"
        ],
        "also": [
          "Agent-ready, a grade of BB or better",
          "Free to start without a card"
        ],
        "goodFor": "A program or bot that needs one governed execution at a time, with a policy, a budget, a sandbox profile and correlation ids it sets itself and a result object it reads back, on a machine it controls, with the model on OpenRouter, a local server or a native Anthropic or OpenAI key.",
        "slug": "axlr",
        "watchFor": "The setup assistant turns autonomy on and leaves the exec sandbox off, so after setup the model's commands run with the person's rights, bar the destructive list"
      },
      {
        "aheadOn": [
          "Maintenance \u0026 community, 85 against 79"
        ],
        "also": [
          "Runs on your own machine"
        ],
        "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": null,
    "job": {
      "capability": "agent.harness",
      "name": "Agent harnesses"
    },
    "others": [
      {
        "json": "https://www.anchorterminal.com/compare/agent-zero-vs-axlr.json",
        "title": "Agent Zero vs AXLR",
        "url": "https://www.anchorterminal.com/compare/agent-zero-vs-axlr"
      },
      {
        "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-axlr.json",
        "title": "Aider vs AXLR",
        "url": "https://www.anchorterminal.com/compare/aider-vs-axlr"
      },
      {
        "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-axlr.json",
        "title": "Amp vs AXLR",
        "url": "https://www.anchorterminal.com/compare/amp-vs-axlr"
      },
      {
        "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-axlr.json",
        "title": "Antigravity CLI vs AXLR",
        "url": "https://www.anchorterminal.com/compare/antigravity-cli-vs-axlr"
      },
      {
        "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-axlr.json",
        "title": "Auggie CLI vs AXLR",
        "url": "https://www.anchorterminal.com/compare/auggie-vs-axlr"
      },
      {
        "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-claude-code.json",
        "title": "AXLR vs Claude Code",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-claude-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-cline.json",
        "title": "AXLR vs Cline",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-cline"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-conductor.json",
        "title": "AXLR vs Conductor",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-conductor"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-crush.json",
        "title": "AXLR vs Crush",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-crush"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-cursor-cli.json",
        "title": "AXLR vs Cursor CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-cursor-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-deepseek-harness.json",
        "title": "AXLR vs DeepSeek Harness (dsh)",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-deepseek-harness"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-deepseek-superagent.json",
        "title": "AXLR vs dsh-superagent (DeepSeek)",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-deepseek-superagent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-devin.json",
        "title": "AXLR vs Devin",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-devin"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-droid-cli.json",
        "title": "AXLR vs Droid CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-droid-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-earendil-pi.json",
        "title": "AXLR vs Pi",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-earendil-pi"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-emdash.json",
        "title": "AXLR vs Emdash",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-emdash"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-gemini-cli.json",
        "title": "AXLR vs Gemini CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-gemini-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-github-copilot-cli.json",
        "title": "AXLR vs GitHub Copilot CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-github-copilot-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-goose.json",
        "title": "AXLR vs goose",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-goose"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-harness2.json",
        "title": "AXLR vs Harness²",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-harness2"
      },
      {
        "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-jules.json",
        "title": "AXLR vs Jules",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-jules"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-junie.json",
        "title": "AXLR vs Junie CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-junie"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-kilo-code-cli.json",
        "title": "AXLR vs Kilo Code CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-kilo-code-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-kimi-code-cli.json",
        "title": "AXLR vs Kimi Code CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-kimi-code-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-kiro-cli.json",
        "title": "AXLR vs Kiro CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-kiro-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-mini-swe-agent.json",
        "title": "AXLR vs mini-swe-agent",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-mini-swe-agent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-minimax-code.json",
        "title": "AXLR vs MiniMax Code",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-minimax-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-mistral-vibe-cli.json",
        "title": "AXLR vs Mistral Vibe CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-mistral-vibe-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-muse-code.json",
        "title": "AXLR vs Muse Code",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-muse-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-openai-agents-api.json",
        "title": "AXLR vs OpenAI Agents API",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-openai-agents-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-openai-codex.json",
        "title": "AXLR vs OpenAI Codex",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-openai-codex"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-opencode.json",
        "title": "AXLR vs OpenCode",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-opencode"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-openhands.json",
        "title": "AXLR vs OpenHands",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-openhands"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-openmausbot.json",
        "title": "AXLR vs OpenMausBot",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-openmausbot"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-orca.json",
        "title": "AXLR vs Orca",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-orca"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-paseo.json",
        "title": "AXLR vs Paseo",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-paseo"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-prime-agent.json",
        "title": "AXLR vs Prime Agent",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-prime-agent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-qoder-cli.json",
        "title": "AXLR vs Qoder CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-qoder-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-qwen-code.json",
        "title": "AXLR vs Qwen Code",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-qwen-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-reflection-mirror.json",
        "title": "AXLR vs Mirror CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-reflection-mirror"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-rovo-dev-cli.json",
        "title": "AXLR vs Rovo Dev CLI",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-rovo-dev-cli"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-sculptor.json",
        "title": "AXLR vs Sculptor",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-sculptor"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-t3-code.json",
        "title": "AXLR vs T3 Code",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-t3-code"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-traycer.json",
        "title": "AXLR vs Traycer",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-traycer"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-unstoppable.json",
        "title": "AXLR vs Unstoppable",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-unstoppable"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-verdent.json",
        "title": "AXLR vs Verdent",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-verdent"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-vibe-trading.json",
        "title": "AXLR vs Vibe-Trading",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-vibe-trading"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-warp.json",
        "title": "AXLR vs Warp (Warp Agent CLI and the Oz Agent API)",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-warp"
      },
      {
        "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-letta.json",
        "title": "Cline vs Letta",
        "url": "https://www.anchorterminal.com/compare/cline-vs-letta"
      },
      {
        "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-letta.json",
        "title": "Crush vs Letta",
        "url": "https://www.anchorterminal.com/compare/crush-vs-letta"
      },
      {
        "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-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-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-letta.json",
        "title": "Devin vs Letta",
        "url": "https://www.anchorterminal.com/compare/devin-vs-letta"
      },
      {
        "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-letta.json",
        "title": "Pi vs Letta",
        "url": "https://www.anchorterminal.com/compare/earendil-pi-vs-letta"
      },
      {
        "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-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-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-letta.json",
        "title": "goose vs Letta",
        "url": "https://www.anchorterminal.com/compare/goose-vs-letta"
      },
      {
        "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-letta.json",
        "title": "HarnessRouter vs Letta",
        "url": "https://www.anchorterminal.com/compare/harnessrouter-vs-letta"
      },
      {
        "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/axlr-vs-clawboo.json",
        "title": "AXLR vs Clawboo",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-clawboo"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-cli-manager.json",
        "title": "AXLR vs CLI Manager",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-cli-manager"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-harness-autonomous.json",
        "title": "AXLR vs Harness",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-harness-autonomous"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-paperclip.json",
        "title": "AXLR vs Paperclip",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-paperclip"
      },
      {
        "json": "https://www.anchorterminal.com/compare/axlr-vs-parallax-agents.json",
        "title": "AXLR vs Parallax",
        "url": "https://www.anchorterminal.com/compare/axlr-vs-parallax-agents"
      },
      {
        "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-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-letta.json",
        "title": "Harness vs Letta",
        "url": "https://www.anchorterminal.com/compare/harness-autonomous-vs-letta"
      },
      {
        "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": [
      {
        "axlr": 70,
        "by": 12,
        "edge": "axlr",
        "key": "reliability",
        "letta": 58,
        "name": "Reliability",
        "weight": 16
      },
      {
        "key": "performance",
        "name": "Performance",
        "pending": true,
        "weight": 10
      },
      {
        "axlr": 80,
        "by": 10,
        "edge": "axlr",
        "key": "schema",
        "letta": 70,
        "name": "Schema \u0026 documentation",
        "weight": 13
      },
      {
        "axlr": 83,
        "by": 16,
        "edge": "axlr",
        "key": "ergonomics",
        "letta": 67,
        "name": "Agent ergonomics",
        "weight": 13
      },
      {
        "axlr": 62,
        "by": 27,
        "edge": "axlr",
        "key": "security",
        "letta": 35,
        "name": "Security \u0026 auth",
        "weight": 14
      },
      {
        "axlr": 60,
        "by": 0,
        "edge": "",
        "key": "payments",
        "letta": 60,
        "name": "Payments \u0026 pricing",
        "weight": 10
      },
      {
        "key": "tasks",
        "name": "Task success",
        "pending": true,
        "weight": 10
      },
      {
        "axlr": 79,
        "by": 6,
        "edge": "letta",
        "key": "maintenance",
        "letta": 85,
        "name": "Maintenance \u0026 community",
        "weight": 7
      },
      {
        "axlr": 55,
        "by": 0,
        "edge": "",
        "key": "transparency",
        "letta": 55,
        "name": "Transparency \u0026 trust",
        "weight": 7
      }
    ],
    "summary": "AXLR scores 70.6 (BB) on agent readiness against Letta's 59.7 (C), and leads in 4 of 7 scored categories. Letta leads on maintenance \u0026 community. Both do agent harnesses.",
    "tasks": null,
    "tutorials": [],
    "verdicts": {
      "axlr": "A pre-1.0 Go harness with an unusually complete service contract, mutual TLS with principal roles, required idempotency keys, a policy, budget and sandbox per execution, and a result object a program can read. The console's defaults after setup are autonomy on and no sandbox, the project has one maintainer and no outside users yet, and releases carry no notes.",
      "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/axlr-vs-letta",
    "json": "https://www.anchorterminal.com/compare/axlr-vs-letta.json",
    "llms": "https://www.anchorterminal.com/llms.txt",
    "markdown": "https://www.anchorterminal.com/compare/axlr-vs-letta.md",
    "mcp": "https://www.anchorterminal.com/mcp",
    "slim": "https://www.anchorterminal.com/compare/axlr-vs-letta.min.md"
  },
  "markdown": "AXLR scores 70.6 (BB) on agent readiness against Letta's 59.7 (C), and leads in 4 of 7 scored categories. Letta leads on maintenance \u0026 community. Both do agent harnesses.\n\n- AXLR: grade BB, 70.6/100, rank #197 of 1486. Markdown https://www.anchorterminal.com/tools/axlr.md · JSON https://www.anchorterminal.com/api/v1/tools/axlr.json\n- Letta: grade C, 59.7/100, rank #684 of 1486. 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### AXLR (BB)\n\nGood for: A program or bot that needs one governed execution at a time, with a policy, a budget, a sandbox profile and correlation ids it sets itself and a result object it reads back, on a machine it controls, with the model on OpenRouter, a local server or a native Anthropic or OpenAI key.\n\nAhead on:\n- Reliability, 70 against 58\n- Schema \u0026 documentation, 80 against 70\n- Agent ergonomics, 83 against 67\n- Security \u0026 auth, 62 against 35\n\nAlso in its favour:\n- Agent-ready, a grade of BB or better\n- Free to start without a card\n\nWatch for: The setup assistant turns autonomy on and leaves the exec sandbox off, so after setup the model's commands run with the person's rights, bar the destructive list\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- Maintenance \u0026 community, 85 against 79\n\nAlso in its favour:\n- Runs on your own machine\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### Security \u0026 auth: AXLR +27\n\n- AXLR (62): Harness reading of the framework checklist, as for the other four harnesses. 30 for what leaves the machine by default, 20 for approvals and sandboxing, 15 for prompt-injection posture, 15 for audit and 20 for the security programme. No product telemetry in the console source (the outbound hosts are openrouter.ai, api.anthropic.com, api.openai.com, a configured local server, api.github.com and github.com for engine downloads, and registry.underpassai.com for the signed catalog index) or in the docs; payload capture is off by default since 9 October 2026, traces omit prompts and credentials, model keys are never given to commands or plugins, and Jev sends requests and answers to TypeSafe only when on, which the setup assistant does when `TYPESAFE_API_KEY` is set, with a notice on stderr (27). Approval cards, a destructive list that always asks, four work modes, a policy level per execution, a bubblewrap or container sandbox with an enforced egress allow list, and a service that approves nothing but reads. Against that, the setup assistant writes `autonomous: true`, `exec_sandbox` is off by default, forged tools run with the person's rights, and the README says the console and worker are not sandboxes (13). Forged tools are refused when a file changes since the forge, a policy forbids calls outside the model, and the docs say MCP tools keep their own side effects, but no prompt-injection guidance was found and MCP results reach the model unmarked (6). The service keeps an event journal, audit records, a receipt with the SHA-256 of every call's arguments and outcome, and correlation ids on every event; the console keeps session records, a redacted app log and `/session` (14). No SECURITY.md, no security.txt on either host, no advisories, no bug bounty; release checksums and a minisign-signed catalog are integrity, not a programme (2). 27+13+6+14+2 = 62.\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### Agent ergonomics: AXLR +16\n\n- AXLR (83): Harness reading of the framework line, scored on what a program driving it has to supply. Six local tools plus the host's bookkeeping tools; work modes and an execution policy hide the tools a run may not use, `axlr_catalog` searches the catalog instead of loading it, forged tools keep the request prefix for the prompt cache, and a context cap of 75,000 prompt tokens opens a successor session (20). `local_read`, `local_search` and `local_list` page with `offset`, `next_offset` and `max_bytes`; `StreamEvents` takes `after`, `max_events` (1 to 256) and `wait_ms`; a budget per execution in seconds, requests, tool calls and dollars; 32 tool calls a turn and `max_session_usd` (20). The `--exec` run ends in one `result` line with a status, the pending call, every call's outcome and the usage, and exits 0, 3 or 1; service errors carry codes an agent can act on; a budget stop says which limit (`budget: requests 20 reached`) and leaves the session resumable (16). `Idempotency-Key` on every turn, approval and direct call with cross-transport replay, `expected_revision` on decisions, `expected_sha256` on worker writes, and an interrupted effectful call left `uncertain` for an operator rather than retried (19). One command runs a task, but the first launch needs an OpenRouter key or a local server, the service needs a CA, a principals file and remote KMP and MADE before a first session, and the only SDK is the Go library (8). 20+20+16+19+8 = 83.\n- Letta (67): Harness reading. Toolsets switch with `/model`, skills load per agent, and subagents run in the background (18 of 25). Context is managed through memory blocks, reflection and dreaming (12 of 20). `letta -p --output-format json` for scripted runs and an App Server for programmatic control (12 of 20). Conversations resume by agent and conversation id, and memory is git-tracked so changes can be reverted (15 of 20). Runs with no account on the local backend, with one SDK language, TypeScript (10 of 15). Total 67.\n\n### Reliability: AXLR +12\n\n- AXLR (70): Read as a local package, as claude-code, goose, opencode and openhands were. Release archives for Linux, macOS and Windows on amd64 and arm64 with a `.sha256` beside each, a GHCR image, an OCI Helm chart and source builds with Go 1.26, all stated in the docs; no Homebrew, npm or apt route (20). CI on main runs vet, race tests and a coverage gate above 80 per cent for both modules, with the sandbox tests required under bubblewrap, and the last ten runs on main to 1 November 2026 all passed; the release workflow tests on six native runners (25). 10 open issues, all opened by the founder on 19 and 21 October 2026 as trackers for service work (work modes, plugins, the sandbox setting, cost limits), none from an outside user and none a crash report, 0 open pull requests and about 100 merged; with 0 stars there is nobody else to report, so the handling of outside reports is untested (20). Tags are semver 0.x and the docs date each behaviour change inline (\"until 14 October 2026…\"), but the 21 releases have empty notes, there is no CHANGELOG.md, and the product contract records one retirement (the seven 1.0 skill definitions on 5 October 2026) without a notice period (5). Pre-1.0, which the README calls an evolving project (0). 20+25+20+5+0 = 70.\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### Schema \u0026 documentation: AXLR +10\n\n- AXLR (80): An OpenAPI 3.1 file for the service (15 paths, 23 schemas, `mutualTLS` security scheme, `additionalProperties: false` on request bodies), a checked proto for the gRPC service, and the 19 MCP tools built from the same shared schemas (25). No llms.txt on either site (404), and the docs site renders HTML; the Markdown sources are in the repository (5). The product contract tables what each of the four interfaces can and cannot do, the work-mode table states each mode's purpose and tool policy, the transport parity ledger names every verb's arguments and behaviour, and `axlr_tools` tells the model to look for a tool before forging one (15). Typed inputs throughout, `Idempotency-Key` 16 to 128 safe ASCII characters, `expected_revision` a positive integer, policy levels, sandbox profiles and egress values enumerated, budgets as four integers, and the service rejects unknown fields, invalid types and bodies over 4 MiB (14). Examples in every guide, an error shape of `code`, `message` and `request_id`, named codes (`409 idempotency_conflict`, `400 invalid_cursor`, `422 invalid_policy`, `invalid_budget`, `sandbox_unavailable`, `not_ready`, `invalid_id`), a gRPC status mapping, and the worker's five statuses and three exit codes; no single error reference page (14). `/v1` routes and an OpenAPI version of 0.1.0 against a 0.15.0 release, and no changelog beyond the dated notes inside the docs (7). 25+5+15+14+14+7 = 80.\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 +6\n\n- AXLR (79): v0.15.0 on 2026-10-25, with commits on main to 2026-11-01 (30). 21 releases between 4 and 25 October 2026 (20). One maintainer (368 of 399 commits, the rest by two agent accounts), 10 open issues that are his own trackers with no comments, about 100 merged pull requests and no outside report to measure a reply against (15). Not in the MCP registry; the Go module and a proto to generate clients from are the only client code, beside the GHCR image and Helm chart (5). Go 1.26 toolchain pinned, release actions pinned by commit SHA, a go-licenses check that the third-party bundle matches the dependency graph, and CI passing on main (9). 30+20+15+5+9 = 79.\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 | AXLR | Letta | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 70 | 58 | AXLR +12 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 80 | 70 | AXLR +10 |\n| Agent ergonomics | 13% (16.2 this run) | 83 | 67 | AXLR +16 |\n| Security \u0026 auth | 14% (17.5 this run) | 62 | 35 | AXLR +27 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 60 | 60 | even |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 79 | 85 | Letta +6 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 55 | 55 | even |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **70.6 · BB** | **59.7 · C** | |\n\n## Facts side by side\n\n| Fact | AXLR | Letta |\n| --- | --- | --- |\n| Kind | Agent harness | Agent harness |\n| Vendor | Underpass AI | Letta |\n| Hosted endpoint | no (local only) | no (local only) |\n| Transports |  | stdio |\n| Auth | OAuth or key | OAuth or key |\n| Pricing | Free | Freemium |\n| x402 | no | no |\n| Licence | Apache-2.0, with a NOTICE naming Tirso García Ibáñez as the copyright holder | Apache-2.0 |\n| Read-only variant documented | no | no |\n| llms.txt | no | yes |\n| Last release | 2026-10-25 | 2026-11-06 |\n| Terms last updated | no document linked | no date given |\n| Privacy policy last updated | no document linked | no date given |\n| Customer content may train models | not read yet | not found in the text |\n| Terms restrict automated access | not read yet | not found in the text |\n| Terms restrict benchmarking | not read yet | not found in the text |\n| Terms or service can change without notice | not read yet | not found in the text |\n| Arbitration or class-action waiver | not read yet | yes |\n| Popularity | 0 stars | 3.8k stars, 86k npm/wk, 2.2k PyPI/wk |\n\n## Verdicts\n\n**AXLR.** A pre-1.0 Go harness with an unusually complete service contract, mutual TLS with principal roles, required idempotency keys, a policy, budget and sandbox per execution, and a result object a program can read. The console's defaults after setup are autonomy on and no sandbox, the project has one maintainer and no outside users yet, and releases carry no notes.\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### AXLR\n\n1. Before the first prompt, set `approvals.autonomous` to false or run with `--approve none`, and turn `exec_sandbox.mode` to `auto` or `required` on Linux; after setup both default the other way\n2. Drive a run with `axlr-tui --exec --json --policy \u003cfile\u003e --budget \u003cfile\u003e --sandbox \u003cfile\u003e` and read only the last `result` line; exit 3 means a call waits for `--decide approve|deny` with `--session \u003cid\u003e`\n3. On the service, send `Idempotency-Key` (16 to 128 safe ASCII characters) on every turn, approval and direct call, and pass the session's `expected_revision`; a reused key with a different body answers 409\n4. A local model must return native tool calls (llama.cpp with `--jinja`, vLLM with `--enable-auto-tool-choice`); set `context_tokens` on the entry and `OLLAMA_CONTEXT_LENGTH` for Ollama\n5. Leave `TYPESAFE_API_KEY` unset unless you want the setup assistant to switch Jev on, which sends requests and final answers to TypeSafe\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, AXLR or Letta?\n\nAXLR scores 70.6 (BB) on agent readiness against Letta's 59.7 (C), and leads in 4 of 7 scored categories. Letta leads on maintenance \u0026 community.\n\n### Are AXLR and Letta open source?\n\nYes. AXLR is open source (Apache-2.0, with a NOTICE naming Tirso García Ibáñez as the copyright holder). Letta is open source (Apache-2.0).\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/axlr-vs-letta.json, and with the fewest tokens: https://www.anchorterminal.com/compare/axlr-vs-letta.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"axlr\", \"b\": \"letta\"}`. From a terminal: `anchor compare axlr letta`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/axlr.json and https://www.anchorterminal.com/api/v1/tools/letta.json\n\n## Other comparisons with AXLR or Letta\n\n- [Agent Zero vs AXLR](https://www.anchorterminal.com/compare/agent-zero-vs-axlr.md)\n- [Agent Zero vs Letta](https://www.anchorterminal.com/compare/agent-zero-vs-letta.md)\n- [Aider vs AXLR](https://www.anchorterminal.com/compare/aider-vs-axlr.md)\n- [Aider vs Letta](https://www.anchorterminal.com/compare/aider-vs-letta.md)\n- [Amp vs AXLR](https://www.anchorterminal.com/compare/amp-vs-axlr.md)\n- [Amp vs Letta](https://www.anchorterminal.com/compare/amp-vs-letta.md)\n- [Antigravity CLI vs AXLR](https://www.anchorterminal.com/compare/antigravity-cli-vs-axlr.md)\n- [Antigravity CLI vs Letta](https://www.anchorterminal.com/compare/antigravity-cli-vs-letta.md)\n- [Auggie CLI vs AXLR](https://www.anchorterminal.com/compare/auggie-vs-axlr.md)\n- [Auggie CLI vs Letta](https://www.anchorterminal.com/compare/auggie-vs-letta.md)\n- [AXLR vs Claude Code](https://www.anchorterminal.com/compare/axlr-vs-claude-code.md)\n- [AXLR vs Cline](https://www.anchorterminal.com/compare/axlr-vs-cline.md)\n- [AXLR vs Conductor](https://www.anchorterminal.com/compare/axlr-vs-conductor.md)\n- [AXLR vs Crush](https://www.anchorterminal.com/compare/axlr-vs-crush.md)\n- [AXLR vs Cursor CLI](https://www.anchorterminal.com/compare/axlr-vs-cursor-cli.md)\n- [AXLR vs DeepSeek Harness (dsh)](https://www.anchorterminal.com/compare/axlr-vs-deepseek-harness.md)\n- [AXLR vs dsh-superagent (DeepSeek)](https://www.anchorterminal.com/compare/axlr-vs-deepseek-superagent.md)\n- [AXLR vs Devin](https://www.anchorterminal.com/compare/axlr-vs-devin.md)\n- [AXLR vs Droid CLI](https://www.anchorterminal.com/compare/axlr-vs-droid-cli.md)\n- [AXLR vs Pi](https://www.anchorterminal.com/compare/axlr-vs-earendil-pi.md)\n- [AXLR vs Emdash](https://www.anchorterminal.com/compare/axlr-vs-emdash.md)\n- [AXLR vs Gemini CLI](https://www.anchorterminal.com/compare/axlr-vs-gemini-cli.md)\n- [AXLR vs GitHub Copilot CLI](https://www.anchorterminal.com/compare/axlr-vs-github-copilot-cli.md)\n- [AXLR vs goose](https://www.anchorterminal.com/compare/axlr-vs-goose.md)\n- [AXLR vs Harness²](https://www.anchorterminal.com/compare/axlr-vs-harness2.md)\n- [AXLR vs HarnessRouter](https://www.anchorterminal.com/compare/axlr-vs-harnessrouter.md)\n- [AXLR vs Jules](https://www.anchorterminal.com/compare/axlr-vs-jules.md)\n- [AXLR vs Junie CLI](https://www.anchorterminal.com/compare/axlr-vs-junie.md)\n- [AXLR vs Kilo Code CLI](https://www.anchorterminal.com/compare/axlr-vs-kilo-code-cli.md)\n- [AXLR vs Kimi Code CLI](https://www.anchorterminal.com/compare/axlr-vs-kimi-code-cli.md)\n- [AXLR vs Kiro CLI](https://www.anchorterminal.com/compare/axlr-vs-kiro-cli.md)\n- [AXLR vs mini-swe-agent](https://www.anchorterminal.com/compare/axlr-vs-mini-swe-agent.md)\n- [AXLR vs MiniMax Code](https://www.anchorterminal.com/compare/axlr-vs-minimax-code.md)\n- [AXLR vs Mistral Vibe CLI](https://www.anchorterminal.com/compare/axlr-vs-mistral-vibe-cli.md)\n- [AXLR vs Muse Code](https://www.anchorterminal.com/compare/axlr-vs-muse-code.md)\n- [AXLR vs OpenAI Agents API](https://www.anchorterminal.com/compare/axlr-vs-openai-agents-api.md)\n- [AXLR vs OpenAI Codex](https://www.anchorterminal.com/compare/axlr-vs-openai-codex.md)\n- [AXLR vs OpenCode](https://www.anchorterminal.com/compare/axlr-vs-opencode.md)\n- [AXLR vs OpenHands](https://www.anchorterminal.com/compare/axlr-vs-openhands.md)\n- [AXLR vs OpenMausBot](https://www.anchorterminal.com/compare/axlr-vs-openmausbot.md)\n- [AXLR vs Orca](https://www.anchorterminal.com/compare/axlr-vs-orca.md)\n- [AXLR vs Paseo](https://www.anchorterminal.com/compare/axlr-vs-paseo.md)\n- [AXLR vs Prime Agent](https://www.anchorterminal.com/compare/axlr-vs-prime-agent.md)\n- [AXLR vs Qoder CLI](https://www.anchorterminal.com/compare/axlr-vs-qoder-cli.md)\n- [AXLR vs Qwen Code](https://www.anchorterminal.com/compare/axlr-vs-qwen-code.md)\n- [AXLR vs Mirror CLI](https://www.anchorterminal.com/compare/axlr-vs-reflection-mirror.md)\n- [AXLR vs Rovo Dev CLI](https://www.anchorterminal.com/compare/axlr-vs-rovo-dev-cli.md)\n- [AXLR vs Sculptor](https://www.anchorterminal.com/compare/axlr-vs-sculptor.md)\n- [AXLR vs T3 Code](https://www.anchorterminal.com/compare/axlr-vs-t3-code.md)\n- [AXLR vs Traycer](https://www.anchorterminal.com/compare/axlr-vs-traycer.md)\n- [AXLR vs Unstoppable](https://www.anchorterminal.com/compare/axlr-vs-unstoppable.md)\n- [AXLR vs Verdent](https://www.anchorterminal.com/compare/axlr-vs-verdent.md)\n- [AXLR vs Vibe-Trading](https://www.anchorterminal.com/compare/axlr-vs-vibe-trading.md)\n- [AXLR vs Warp (Warp Agent CLI and the Oz Agent API)](https://www.anchorterminal.com/compare/axlr-vs-warp.md)\n- [Claude Code vs Letta](https://www.anchorterminal.com/compare/claude-code-vs-letta.md)\n- [Cline vs Letta](https://www.anchorterminal.com/compare/cline-vs-letta.md)\n- [Conductor vs Letta](https://www.anchorterminal.com/compare/conductor-vs-letta.md)\n- [Crush vs Letta](https://www.anchorterminal.com/compare/crush-vs-letta.md)\n- [Cursor CLI vs Letta](https://www.anchorterminal.com/compare/cursor-cli-vs-letta.md)\n- [DeepSeek Harness (dsh) vs Letta](https://www.anchorterminal.com/compare/deepseek-harness-vs-letta.md)\n- [dsh-superagent (DeepSeek) vs Letta](https://www.anchorterminal.com/compare/deepseek-superagent-vs-letta.md)\n- [Devin vs Letta](https://www.anchorterminal.com/compare/devin-vs-letta.md)\n- [Droid CLI vs Letta](https://www.anchorterminal.com/compare/droid-cli-vs-letta.md)\n- [Pi vs Letta](https://www.anchorterminal.com/compare/earendil-pi-vs-letta.md)\n- [Emdash vs Letta](https://www.anchorterminal.com/compare/emdash-vs-letta.md)\n- [Gemini CLI vs Letta](https://www.anchorterminal.com/compare/gemini-cli-vs-letta.md)\n- [GitHub Copilot CLI vs Letta](https://www.anchorterminal.com/compare/github-copilot-cli-vs-letta.md)\n- [goose vs Letta](https://www.anchorterminal.com/compare/goose-vs-letta.md)\n- [Harness² vs Letta](https://www.anchorterminal.com/compare/harness2-vs-letta.md)\n- [HarnessRouter vs Letta](https://www.anchorterminal.com/compare/harnessrouter-vs-letta.md)\n- [Jules vs Letta](https://www.anchorterminal.com/compare/jules-vs-letta.md)\n- [Junie CLI vs Letta](https://www.anchorterminal.com/compare/junie-vs-letta.md)\n- [Kilo Code CLI vs Letta](https://www.anchorterminal.com/compare/kilo-code-cli-vs-letta.md)\n- [Kimi Code CLI vs Letta](https://www.anchorterminal.com/compare/kimi-code-cli-vs-letta.md)\n- [Kiro CLI vs Letta](https://www.anchorterminal.com/compare/kiro-cli-vs-letta.md)\n- [Letta vs mini-swe-agent](https://www.anchorterminal.com/compare/letta-vs-mini-swe-agent.md)\n- [Letta vs MiniMax Code](https://www.anchorterminal.com/compare/letta-vs-minimax-code.md)\n- [Letta vs Mistral Vibe CLI](https://www.anchorterminal.com/compare/letta-vs-mistral-vibe-cli.md)\n- [Letta vs Muse Code](https://www.anchorterminal.com/compare/letta-vs-muse-code.md)\n- [Letta vs OpenAI Agents API](https://www.anchorterminal.com/compare/letta-vs-openai-agents-api.md)\n- [Letta vs OpenAI Codex](https://www.anchorterminal.com/compare/letta-vs-openai-codex.md)\n- [Letta vs OpenCode](https://www.anchorterminal.com/compare/letta-vs-opencode.md)\n- [Letta vs OpenHands](https://www.anchorterminal.com/compare/letta-vs-openhands.md)\n- [Letta vs OpenMausBot](https://www.anchorterminal.com/compare/letta-vs-openmausbot.md)\n- [Letta vs Orca](https://www.anchorterminal.com/compare/letta-vs-orca.md)\n- [Letta vs Paseo](https://www.anchorterminal.com/compare/letta-vs-paseo.md)\n- [Letta vs Prime Agent](https://www.anchorterminal.com/compare/letta-vs-prime-agent.md)\n- [Letta vs Qoder 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- [AXLR vs Clawboo](https://www.anchorterminal.com/compare/axlr-vs-clawboo.md)\n- [AXLR vs CLI Manager](https://www.anchorterminal.com/compare/axlr-vs-cli-manager.md)\n- [AXLR vs Harness](https://www.anchorterminal.com/compare/axlr-vs-harness-autonomous.md)\n- [AXLR vs Paperclip](https://www.anchorterminal.com/compare/axlr-vs-paperclip.md)\n- [AXLR vs Parallax](https://www.anchorterminal.com/compare/axlr-vs-parallax-agents.md)\n- [Clawboo vs Letta](https://www.anchorterminal.com/compare/clawboo-vs-letta.md)\n- [CLI Manager vs Letta](https://www.anchorterminal.com/compare/cli-manager-vs-letta.md)\n- [Harness vs Letta](https://www.anchorterminal.com/compare/harness-autonomous-vs-letta.md)\n- [Letta vs Paperclip](https://www.anchorterminal.com/compare/letta-vs-paperclip.md)\n- [Letta vs Parallax](https://www.anchorterminal.com/compare/letta-vs-parallax-agents.md)\n",
  "meta": {
    "attribution": "Anchor Terminal (https://www.anchorterminal.com)",
    "attributionRequired": true,
    "credit": "CC BY 4.0, credit Anchor Terminal and link the page or API address you took it from (https://www.anchorterminal.com/terms/#data)",
    "docs": "https://www.anchorterminal.com/docs/",
    "generatedAt": "2026-11-07",
    "license": "CC-BY-4.0",
    "method": "https://www.anchorterminal.com/benchmark/",
    "methodology": "0.7",
    "openapi": "https://www.anchorterminal.com/openapi.json",
    "preview": false,
    "run": "2026-10-01",
    "runLabel": "October 2026 research run",
    "terms": "https://www.anchorterminal.com/terms/#data"
  },
  "page": {
    "breadcrumbs": [
      {
        "name": "Home",
        "url": "https://www.anchorterminal.com/"
      },
      {
        "name": "Compare",
        "url": "https://www.anchorterminal.com/compare/"
      },
      {
        "name": "AXLR vs Letta",
        "url": ""
      }
    ],
    "description": "AXLR scores 70.6 (BB) to Letta's 59.7 (C) for agent harnesses. Prices, MCP, x402, uptime and agent notes side by side.",
    "facts": [
      "AXLR BB 70.6",
      "Letta C 59.7",
      "scores"
    ],
    "h1": "AXLR vs Letta",
    "image": "https://www.anchorterminal.com/assets/og/default.png",
    "path": "/compare/axlr-vs-letta",
    "published": "2026-10-01",
    "section": "tools",
    "title": "AXLR vs Letta for AI agents in 2026: scores and prices",
    "toc": null,
    "updated": "2026-11-07",
    "url": "https://www.anchorterminal.com/compare/axlr-vs-letta"
  },
  "tokens": {
    "markdown": 6750,
    "slim": 3180
  },
  "version": 1
}
