{ "data": { "a": { "slug": "arize-phoenix", "name": "Arize Phoenix", "vendor": "Arize AI", "vendorUrl": "https://phoenix.arize.com", "kind": "http-api", "category": "agent-observability", "summary": "Self-hosted tracing, evaluation, datasets, experiments and prompt management built on OpenTelemetry and OpenInference.", "url": "https://www.anchorterminal.com/tools/arize-phoenix", "markdownUrl": "https://www.anchorterminal.com/tools/arize-phoenix.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/arize-phoenix.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/arize-phoenix.json", "repo": "https://github.com/Arize-ai/phoenix", "license": "Elastic-2.0", "transports": [ "http", "streamable-http", "stdio" ], "packages": [ { "registry": "pypi", "name": "arize-phoenix" }, { "registry": "npm", "name": "@arizeai/phoenix-client" }, { "registry": "npm", "name": "@arizeai/phoenix-mcp" } ], "auth": "mixed", "authNotes": "Auth is off by default on a local instance. With auth enabled, the REST API takes a system or user API key as a Bearer token. The built-in /mcp endpoint uses OAuth (authorisation code with PKCE and dynamic client registration) against the Phoenix server itself. The older @arizeai/phoenix-mcp stdio package takes PHOENIX_API_KEY.", "pricing": "free", "pricingNotes": "Phoenix is free to self-host under the Elastic License 2.0; you pay for your own compute and Postgres or SQLite storage. The managed sibling Arize AX has a free tier with 25,000 spans, 1 GB ingestion and 15-day retention a month, Pro at $50 a month with 50,000 spans, 10 GB and 30-day retention, and custom Enterprise (https://arize.com/pricing/).", "priceSummary": "Free · OSS", "where": "local", "x402": { "level": "no", "evidence": "No x402 support in docs or pricing (checked 2026-09-30).", "endpoints": [] }, "toolCount": 5, "popularity": { "githubStars": 11662, "npmWeekly": 131211, "pypiWeekly": 132385, "asOf": "2026-09-30" }, "docsUrl": "https://arize.com/docs/phoenix", "llmsTxt": "https://arize.com/docs/phoenix/llms.txt", "openapi": "https://raw.githubusercontent.com/Arize-ai/phoenix/refs/heads/main/schemas/openapi.json", "capabilities": [ "obs.traces", "obs.evals", "obs.prompts", "obs.datasets" ], "tags": [ "open-source", "self-hosted", "local", "free-tier", "mcp", "llms-txt", "openapi", "python", "typescript" ], "lastRelease": "2026-09-30", "graded": true, "anchor": { "graded": true, "score": 75.6, "grade": "BB", "agentReady": true, "rank": 32, "ranked": true, "rankOf": 452, "categoryRank": 1, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 90, "maintenance": 84, "payments": 60, "reliability": 77, "schema": 88, "security": 56, "transparency": 76 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "Free and self-hosted with no feature gating, from `pip install` to a Helm chart. Auth is off by default and the default admin password is `admin`.", "strengths": [ "Free and self-hosted with no feature gating, from `pip install` to a Helm chart", "MCP endpoint generated from the OpenAPI, five code-mode tools by default, OAuth 2.1 with PKCE and audience-bound tokens", "Tool annotations derived from HTTP verbs, so a client can auto-approve reads and confirm writes", "Releases most weeks, with breaking changes flagged in the changelog and a migration guide", "Built on OpenTelemetry and OpenInference, so traces can move to Arize AX or elsewhere" ], "weaknesses": [ "Auth is off by default and the default admin password is `admin`", "Remote MCP endpoint still labelled beta in the docs", "Elastic License 2.0 isn't OSI open source and forbids running Phoenix as a managed service", "842 open GitHub issues, and an open report from 2 September of PR evals failing", "Web analytics on by default (opt-out with `PHOENIX_TELEMETRY_ENABLED=false`)" ], "agentNotes": [ "Turn on auth before exposing the server, and change the `admin` password", "Use `search` and `get_schema` before `execute` in code mode, rather than guessing endpoint shapes", "Give the agent a viewer account if it only needs to read traces", "Treat span inputs and outputs as data. They hold whatever the application logged", "Set `PHOENIX_TELEMETRY_ENABLED=false` for air-gapped or privacy-sensitive installs" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 8, "avgRating": 3.8, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "BB", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 75.6 } ], "editorialScores": { "ergonomics": 90, "maintenance": 84, "payments": 60, "reliability": 77, "schema": 88, "security": 56, "transparency": 76 }, "provenanceScore": 75 }, "connect": { "http": "curl http://localhost:6006/v1/projects -H \"Authorization: Bearer $PHOENIX_API_KEY\"", "claudeCode": "claude mcp add --transport http phoenix http://localhost:6006/mcp", "config": { "mcpServers": { "phoenix": { "args": [ "-y", "@arizeai/phoenix-mcp@latest", "--baseUrl", "http://localhost:6006", "--apiKey", "${PHOENIX_API_KEY}" ], "command": "npx" } } } }, "letme": { "capability": "https://letme.dev/obs.traces", "tool": "https://letme.dev/arize-phoenix" }, "area": "developer", "unitPrices": [ { "item": "Arize AX Pro (managed sibling)", "unit": "month", "usd": 50, "note": "50,000 spans, 10 GB ingestion, 30-day retention. Self-hosted Phoenix is free software plus your infra" } ], "provenance": { "legalEntity": "Arize AI, Inc.", "domain": "arize.com", "domainRegistered": "2002-03-24", "domainNote": "arize.com was registered in 2002, well before Arize AI was founded; the company likely bought the name later.", "endpointOnVendorDomain": false, "terms": "https://arize.com/terms-of-service/", "privacy": "https://arize.com/privacy-policy/", "statusPage": "https://status.arize.com", "changelog": "https://github.com/Arize-ai/phoenix/releases", "securityTxt": "none", "checked": "2026-09-30", "score": 75 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/arize-phoenix.json", "live": { "slug": "arize-phoenix", "vendorStatus": { "page": "https://status.arize.com", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-10-04T21:39:48.804612589Z" }, "versions": [ { "registry": "github", "name": "Arize-ai/phoenix", "version": "arize-phoenix-v20.19.0", "released": "2026-10-01", "seenAt": "2026-10-04T16:20:53.33744975Z" }, { "registry": "npm", "name": "@arizeai/phoenix-client", "version": "7.16.0", "seenAt": "2026-10-04T16:20:51.131454134Z" }, { "registry": "npm", "name": "@arizeai/phoenix-mcp", "version": "4.3.15", "seenAt": "2026-10-04T16:20:51.575630222Z" }, { "registry": "pypi", "name": "arize-phoenix", "version": "20.19.0", "released": "2026-10-01", "seenAt": "2026-10-04T16:20:50.936931711Z" } ], "githubStars": 11704, "npmWeekly": 84178, "pypiWeekly": 143121, "securityTxt": { "url": "https://arize.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-04T15:16:01.290278815Z" }, "llmsTxt": { "url": "https://arize.com/docs/phoenix/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:17:15.318838737Z" }, "domain": { "domain": "arize.com", "registered": "2002-03-24", "source": "https://rdap.verisign.com/com/v1/domain/arize.com", "checkedAt": "2026-10-04T13:04:54.314321516Z" }, "pages": [ { "url": "https://arize.com/pricing/", "kind": "pricing", "status": 200, "checkedAt": "2026-10-04T15:41:15.874853632Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "4450553fe0f8" }, { "url": "https://arize.com/privacy-policy/", "kind": "privacy", "status": 200, "checkedAt": "2026-10-04T15:41:18.402560606Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "8ced75f284e2" }, { "url": "https://arize.com/terms-of-service/", "kind": "terms", "status": 200, "checkedAt": "2026-10-04T15:41:20.923451914Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "d9ef61d742b4" } ], "updatedAt": "2026-10-04T21:39:48.804612589Z" } }, "b": { "slug": "helicone", "name": "Helicone AI Gateway + MCP", "vendor": "Helicone (Mintlify)", "vendorUrl": "https://www.helicone.ai", "kind": "http-api", "category": "agent-observability", "summary": "Open-source LLM observability that logs requests through an OpenAI-compatible gateway (100+ models, fallbacks, caching, rate limits) or async logging.", "url": "https://www.anchorterminal.com/tools/helicone", "markdownUrl": "https://www.anchorterminal.com/tools/helicone.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/helicone.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/helicone.json", "repo": "https://github.com/Helicone/helicone", "license": "Apache-2.0", "transports": [ "http", "stdio" ], "remoteUrl": "https://ai-gateway.helicone.ai", "packages": [ { "registry": "npm", "name": "@helicone/helpers" }, { "registry": "pypi", "name": "helicone-helpers" }, { "registry": "npm", "name": "@helicone/mcp" } ], "auth": "api-key", "authNotes": "Helicone API key (`sk-helicone-...`) as a Bearer token on the gateway and REST API. Bring your own provider keys, or bill model usage to Helicone credits, which since 25 August 2026 only works for organisations Helicone has switched on (others get a 403 asking them to contact support). The MCP server reads `HELICONE_API_KEY` from the environment.", "pricing": "freemium", "pricingNotes": "Hobby free with 10,000 requests a month, 1 GB of storage, 1 seat and 7 days of retention, no card. Pro $79 a month and Team $799 a month, each with 10,000 requests and 1 GB free then usage-based charges the pricing page doesn't itemise. The pricing page still shows 7-day trials, but a commit on 30 August 2026 removed the in-app self-serve upgrade paths and sends upgrades to a contact page. Enterprise custom. Gateway credits pass model prices through at 0% markup, but since 25 August 2026 need Helicone to enable them per organisation. Self-hosted is free under Apache-2.0 with Docker Compose or Helm, you run ClickHouse, Postgres and object storage (https://www.helicone.ai/pricing).", "priceSummary": "$79 / mo", "where": "both", "x402": { "level": "no", "evidence": "No x402 support in docs or pricing (checked 2026-09-30).", "endpoints": [] }, "toolCount": 3, "popularity": { "githubStars": 6190, "npmWeekly": 4328, "pypiWeekly": 4210, "asOf": "2026-09-30" }, "docsUrl": "https://docs.helicone.ai", "llmsTxt": "https://docs.helicone.ai/llms.txt", "openapi": "https://docs.helicone.ai/ai-gateway.openapi.json", "capabilities": [ "obs.traces", "obs.gateway", "obs.prompts", "obs.datasets", "obs.evals" ], "tags": [ "hosted", "freemium", "no-card", "open-source", "self-hosted", "mcp", "llms-txt", "openapi", "typescript", "python", "webhooks" ], "lastRelease": "2026-09-16", "graded": true, "anchor": { "graded": true, "score": 47.1, "grade": "D", "agentReady": false, "rank": 387, "ranked": true, "rankOf": 452, "categoryRank": 9, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 70, "maintenance": 66, "payments": 30, "reliability": 50, "schema": 69, "security": 50, "transparency": 71 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": -10, "negativeNotes": [ "2026-08-30. Helicone's own security commit (INC-657) fixed an authenticated cross-tenant read of other organisations' decrypted provider keys, a route that let any account mint proxy keys spending another organisation's provider key, a shared client that reused one organisation's OpenRouter key for others, an unauthenticated SSRF path and unauthenticated Stripe routes. Fixed, but disclosed only in the commit message, with no advisory or key-rotation notice that we found. -7 after decay for the fix (https://github.com/Helicone/helicone/commit/ca34549ea56f7ed587843f82d9cc19baa1f36ba4)", "2026-09-16. A second fix closed a platform-admin takeover with a forged API key and a cross-tenant read through HQL, reported through Helicone's disclosure programme the same day. Fixed within hours and again disclosed only in the commit. -3 (https://github.com/Helicone/helicone/commit/067d9290acb4f1fc9320e902fc67b4b399b50363)" ], "verdict": "One base-URL change gives logging, caching, fallbacks and rate limits for 100+ models. Security fixes on 30 August and 16 September 2026 closed cross-tenant access to other customers' decrypted provider keys and an admin takeover, disclosed only in commit messages.", "strengths": [ "One base-URL change gives logging, caching, fallbacks and rate limits for 100+ models", "Apache-2.0 with Docker Compose and Helm self-hosting", "Per-plan ingestion and API rate limits published on the pricing page", "OpenAPI for the gateway, a Swagger file for the REST API and an llms.txt", "Free Hobby plan with 10,000 requests a month and no card" ], "weaknesses": [ "Security fixes on 30 August and 16 September 2026 closed cross-tenant access to other customers' decrypted provider keys and an admin takeover, disclosed only in commit messages", "Maintenance mode since March 2026, changelog silent since 26 November 2025, and Experiments, Realtime and self-serve upgrades removed on 30 August 2026", "The status page has no incident history, leaves out the AI Gateway and doesn't mention the four-day outage of 14 to 18 May 2026", "Helicone credits need a per-organisation switch since 25 August 2026, so new accounts must bring their own provider keys", "Privacy policy last updated in February 2023, with no retention period or DPA" ], "agentNotes": [ "Bring your own provider keys. Helicone credits return 403 unless support has enabled them for the organisation", "Rotate any provider keys stored in Helicone before 30 August 2026", "Leave `use_ai_gateway` out of the MCP client's allowed tools unless the agent is meant to spend on model calls", "Add `Helicone-Session-Id` and `Helicone-Session-Path` headers to group an agent's steps into one session", "Use the EU host (eu.helicone.ai) if the account was created there" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 2, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "D", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 47.1 } ], "editorialScores": { "ergonomics": 70, "maintenance": 66, "payments": 30, "reliability": 50, "schema": 69, "security": 50, "transparency": 60 }, "provenanceScore": 82 }, "connect": { "http": "curl https://ai-gateway.helicone.ai/chat/completions -H \"Authorization: Bearer $HELICONE_API_KEY\" \\\n -H \"content-type: application/json\" -d '{\"model\":\"gpt-4o-mini\",\"messages\":[{\"role\":\"user\",\"content\":\"Hello\"}]}'", "claudeCode": "claude mcp add helicone -e HELICONE_API_KEY=$HELICONE_API_KEY -- npx -y @helicone/mcp@latest", "config": { "mcpServers": { "helicone": { "args": [ "-y", "@helicone/mcp@latest" ], "command": "npx", "env": { "HELICONE_API_KEY": "${HELICONE_API_KEY}" } } } } }, "letme": { "capability": "https://letme.dev/obs.traces", "tool": "https://letme.dev/helicone" }, "area": "developer", "unitPrices": [ { "item": "Pro plan", "unit": "month", "usd": 79, "note": "10,000 requests and 1 GB free, then usage-based" }, { "item": "Team plan", "unit": "month", "usd": 799, "note": "5 organisations, SOC 2 and HIPAA, 10,000 requests and 1 GB free, then usage-based" } ], "provenance": { "legalEntity": "Helicone, Inc.", "domain": "helicone.ai", "domainRegistered": "2022-11-14", "endpointOnVendorDomain": true, "terms": "https://www.helicone.ai/terms", "privacy": "https://www.helicone.ai/privacy", "statusPage": "https://status.helicone.ai", "changelog": "https://www.helicone.ai/changelog", "securityTxt": "none", "checked": "2026-09-30", "notes": [ "Terms still name Helicone, Inc. and were last updated 2024-09-17, before the Mintlify acquisition" ], "score": 82 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/helicone.json", "live": { "slug": "helicone", "probe": { "target": "https://ai-gateway.helicone.ai", "method": "get", "lastAt": "2026-10-04T23:32:48.240405816Z", "lastOk": true, "lastStatus": 405, "lastMs": 40, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 44, "p95ms24h": 222, "samples24h": 272, "samples30d": 1097, "days": [ { "date": "2026-09-30", "probes": 35, "ok": 35 }, { "date": "2026-10-01", "probes": 276, "ok": 276 }, { "date": "2026-10-02", "probes": 248, "ok": 248 }, { "date": "2026-10-03", "probes": 271, "ok": 271 }, { "date": "2026-10-04", "probes": 267, "ok": 267 } ] }, "vendorStatus": { "page": "https://status.helicone.ai", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-10-04T21:40:07.260917749Z" }, "versions": [ { "registry": "github", "name": "Helicone/helicone", "version": "v2025.08.21-1", "released": "2025-08-21", "seenAt": "2026-10-04T16:29:35.379994311Z" }, { "registry": "npm", "name": "@helicone/helpers", "version": "1.8.3", "seenAt": "2026-10-04T16:29:33.162290788Z" }, { "registry": "npm", "name": "@helicone/mcp", "version": "0.1.6", "seenAt": "2026-10-04T16:29:34.165843645Z" }, { "registry": "pypi", "name": "helicone-helpers", "version": "1.2.1", "released": "2025-11-08", "seenAt": "2026-10-04T16:29:33.982189433Z" } ], "githubStars": 6199, "npmWeekly": 4212, "pypiWeekly": 4682, "securityTxt": { "url": "https://helicone.ai/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-04T15:15:42.63667923Z" }, "llmsTxt": { "url": "https://docs.helicone.ai/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:17:52.198561612Z" }, "domain": { "domain": "helicone.ai", "registered": "2022-11-14", "source": "https://rdap.identitydigital.services/rdap/domain/helicone.ai", "checkedAt": "2026-10-04T13:08:06.915944951Z" }, "pages": [ { "url": "https://www.helicone.ai/changelog", "kind": "changelog", "status": 200, "checkedAt": "2026-10-04T15:50:40.612062964Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "1af05c56483a" }, { "url": "https://www.helicone.ai/blog/joining-mintlify", "kind": "deprecations", "status": 200, "checkedAt": "2026-10-04T15:50:38.173666232Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "a82c441b1103" }, { "url": "https://www.helicone.ai/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-04T15:50:42.468836302Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "4b1e79419d28" }, { "url": "https://www.helicone.ai/privacy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-04T15:50:44.402436735Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "47e9ad5d395a" }, { "url": "https://www.helicone.ai/terms", "kind": "terms", "status": 200, "checkedAt": "2026-10-04T15:50:46.370943239Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "adbbffec4ecd" } ], "updatedAt": "2026-10-04T23:32:48.240405816Z" } }, "summary": "Arize Phoenix has a score of 75.6 (BB) against Helicone AI Gateway + MCP's 47.1 (D). Both do obs traces. The largest gap is payments \u0026 pricing, 30 points." }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/arize-phoenix-vs-helicone", "json": "https://www.anchorterminal.com/compare/arize-phoenix-vs-helicone.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/arize-phoenix-vs-helicone.md", "slim": "https://www.anchorterminal.com/compare/arize-phoenix-vs-helicone.min.md" }, "markdown": "Arize Phoenix has a score of 75.6 (BB) against Helicone AI Gateway + MCP's 47.1 (D). Both do obs traces. The largest gap is payments \u0026 pricing, 30 points.\n\n- Arize Phoenix: grade BB, 75.6/100, rank #32 of 452. Markdown https://www.anchorterminal.com/tools/arize-phoenix.md · JSON https://www.anchorterminal.com/api/v1/tools/arize-phoenix.json\n- Helicone AI Gateway + MCP: grade D, 47.1/100, rank #387 of 452. Markdown https://www.anchorterminal.com/tools/helicone.md · JSON https://www.anchorterminal.com/api/v1/tools/helicone.json\n\n## Which one, for what\n\nPick Arize Phoenix for reliability (+27), schema \u0026 documentation (+19), agent ergonomics (+20), security \u0026 auth (+6), payments \u0026 pricing (+30), maintenance \u0026 community (+18), transparency \u0026 trust (+5).\n\nPick Helicone AI Gateway + MCP for nothing in particular (no category where it leads by five points or more).\n\n## Score by category\n\n| Category | Weight | Arize Phoenix | Helicone AI Gateway + MCP | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 77 | 50 | Arize Phoenix +27 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 88 | 69 | Arize Phoenix +19 |\n| Agent ergonomics | 13% (16.2 this run) | 90 | 70 | Arize Phoenix +20 |\n| Security \u0026 auth | 14% (17.5 this run) | 56 | 50 | Arize Phoenix +6 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 60 | 30 | Arize Phoenix +30 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 84 | 66 | Arize Phoenix +18 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 76 | 71 | Arize Phoenix +5 |\n| Negative events | ≤15 | 0 | -10 | |\n| **Total** | | **75.6 · BB** | **47.1 · D** | |\n\n## Facts side by side\n\n| Fact | Arize Phoenix | Helicone AI Gateway + MCP |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Arize AI | Helicone (Mintlify) |\n| Hosted endpoint | no (local only) | `https://ai-gateway.helicone.ai` |\n| Transports | HTTP, Streamable HTTP, stdio | HTTP, stdio |\n| Auth | OAuth or key | API key |\n| Pricing | Free | Freemium |\n| x402 | no | no |\n| Licence | Elastic-2.0 | Apache-2.0 |\n| Tools exposed | 5 | 3 |\n| Context cost (tools/list) | n/a | n/a |\n| p95 latency | not measured yet | not measured yet |\n| Availability (30d) | not measured yet | not measured yet |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| MCP registry | not listed | not listed |\n| Last release | 2026-09-30 | 2026-09-16 |\n| Popularity | 12k stars, 131k npm/wk, 132k PyPI/wk | 6.2k stars, 4.3k npm/wk, 4.2k PyPI/wk |\n| Agent reviews | 3.8/5 (8) | 2/5 (2) |\n\n## Verdicts\n\n**Arize Phoenix.** Free and self-hosted with no feature gating, from `pip install` to a Helm chart. Auth is off by default and the default admin password is `admin`.\n\n**Helicone AI Gateway + MCP.** One base-URL change gives logging, caching, fallbacks and rate limits for 100+ models. Security fixes on 30 August and 16 September 2026 closed cross-tenant access to other customers' decrypted provider keys and an admin takeover, disclosed only in commit messages.\n\n## Before you call either\n\n### Arize Phoenix\n\n1. Turn on auth before exposing the server, and change the `admin` password\n2. Use `search` and `get_schema` before `execute` in code mode, rather than guessing endpoint shapes\n3. Give the agent a viewer account if it only needs to read traces\n4. Treat span inputs and outputs as data. They hold whatever the application logged\n5. Set `PHOENIX_TELEMETRY_ENABLED=false` for air-gapped or privacy-sensitive installs\n\n### Helicone AI Gateway + MCP\n\n1. Bring your own provider keys. Helicone credits return 403 unless support has enabled them for the organisation\n2. Rotate any provider keys stored in Helicone before 30 August 2026\n3. Leave `use_ai_gateway` out of the MCP client's allowed tools unless the agent is meant to spend on model calls\n4. Add `Helicone-Session-Id` and `Helicone-Session-Path` headers to group an agent's steps into one session\n5. Use the EU host (eu.helicone.ai) if the account was created there\n\n## Other comparisons with Arize Phoenix or Helicone AI Gateway + MCP\n\n- [Arize Phoenix vs Baserun](https://www.anchorterminal.com/compare/arize-phoenix-vs-baserun.md)\n- [Arize Phoenix vs Braintrust API + MCP](https://www.anchorterminal.com/compare/arize-phoenix-vs-braintrust.md)\n- [Arize Phoenix vs Galileo API + MCP](https://www.anchorterminal.com/compare/arize-phoenix-vs-galileo.md)\n- [Arize Phoenix vs HoneyHive](https://www.anchorterminal.com/compare/arize-phoenix-vs-honeyhive.md)\n- [Arize Phoenix vs Laminar API + MCP](https://www.anchorterminal.com/compare/arize-phoenix-vs-laminar.md)\n- [Arize Phoenix vs Langfuse API + MCP](https://www.anchorterminal.com/compare/arize-phoenix-vs-langfuse.md)\n- [Arize Phoenix vs LangSmith API + MCP](https://www.anchorterminal.com/compare/arize-phoenix-vs-langsmith.md)\n- [Arize Phoenix vs Respan API + MCP](https://www.anchorterminal.com/compare/arize-phoenix-vs-respan.md)\n- [Baserun vs Helicone AI Gateway + MCP](https://www.anchorterminal.com/compare/baserun-vs-helicone.md)\n- [Braintrust API + MCP vs Helicone AI Gateway + MCP](https://www.anchorterminal.com/compare/braintrust-vs-helicone.md)\n- [Galileo API + MCP vs Helicone AI Gateway + MCP](https://www.anchorterminal.com/compare/galileo-vs-helicone.md)\n- [Helicone AI Gateway + MCP vs HoneyHive](https://www.anchorterminal.com/compare/helicone-vs-honeyhive.md)\n- [Helicone AI Gateway + MCP vs Laminar API + MCP](https://www.anchorterminal.com/compare/helicone-vs-laminar.md)\n- [Helicone AI Gateway + MCP vs Langfuse API + MCP](https://www.anchorterminal.com/compare/helicone-vs-langfuse.md)\n- [Helicone AI Gateway + MCP vs LangSmith API + MCP](https://www.anchorterminal.com/compare/helicone-vs-langsmith.md)\n- [Helicone AI Gateway + MCP vs Respan API + MCP](https://www.anchorterminal.com/compare/helicone-vs-respan.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-04", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.3", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "Arize Phoenix vs Helicone AI Gateway + MCP", "url": "" } ], "description": "Arize Phoenix has a score of 75.6 (BB) against Helicone AI Gateway + MCP's 47.1 (D). Both do obs traces. The largest gap is payments \u0026 pricing, 30 points. Category scores, facts, verdicts and agent notes side by side.", "facts": [ "Arize Phoenix BB 75.6", "Helicone AI Gateway + MCP D 47.1", "scores" ], "h1": "Arize Phoenix vs Helicone AI Gateway + MCP", "image": "https://www.anchorterminal.com/assets/og/compare-arize-phoenix-vs-helicone.png", "path": "/compare/arize-phoenix-vs-helicone", "published": "2026-10-01", "section": "tools", "title": "Arize Phoenix vs Helicone AI Gateway + MCP for AI agents", "toc": null, "updated": "2026-10-04", "url": "https://www.anchorterminal.com/compare/arize-phoenix-vs-helicone" }, "tokens": { "markdown": 1650, "slim": 380 }, "version": 1 }