{
  "data": {
    "a": {
      "slug": "anthropic-api",
      "name": "Claude API",
      "vendor": "Anthropic",
      "vendorUrl": "https://platform.claude.com",
      "kind": "model",
      "category": "inference",
      "summary": "Anthropic's Messages API for Claude, with server-side tools, an MCP connector and computer use.",
      "url": "https://www.anchorterminal.com/tools/anthropic-api",
      "markdownUrl": "https://www.anchorterminal.com/tools/anthropic-api.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/anthropic-api.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/anthropic-api.json",
      "repo": "https://github.com/anthropics/anthropic-sdk-python",
      "license": "MIT (SDKs)",
      "transports": [
        "http"
      ],
      "remoteUrl": "https://api.anthropic.com/v1/messages",
      "packages": [
        {
          "registry": "pypi",
          "name": "anthropic"
        },
        {
          "registry": "npm",
          "name": "@anthropic-ai/sdk"
        }
      ],
      "auth": "api-key",
      "authNotes": "`Authorization: Bearer` header, with the legacy `x-api-key` header still accepted, plus `anthropic-version`. Personal and service-account keys are created in the Console for one workspace or several.",
      "pricing": "usage",
      "pricingNotes": "Prepaid credits. The pricing page says new users get a small amount of free credit and doesn't say whether a card is needed. Batch is half price. Cache writes cost 1.25x input for 5 minutes or 2x for an hour, reads 0.1x (0.05x on Opus 5.5 and Sonnet 5.5, 0.025x on Fable 5.1). Haiku 5.5 is priced by prompt length, $0.10/$0.50 per million up to 100,000 prompt tokens and $0.50/$2.50 above. US-only inference costs 1.1x. Fast mode on Opus 5.5 (research preview) costs $8/$40 per million. Web search $10 per 1,000, web fetch billed as tokens only, code execution free alongside them or $0.05 per container hour after 1,550 free hours a month (https://platform.claude.com/docs/en/about-claude/pricing).",
      "priceSummary": "from $0.10 / 1M in",
      "where": "hosted",
      "x402": {
        "level": "no",
        "evidence": "No machine payment. Access needs a Console account with a card on file.",
        "endpoints": []
      },
      "toolCount": null,
      "popularity": {
        "githubStars": 3900,
        "npmWeekly": null,
        "pypiWeekly": null,
        "asOf": "2026-09-26"
      },
      "docsUrl": "https://platform.claude.com/docs",
      "rateLimitsUrl": "https://platform.claude.com/docs/en/api/rate-limits",
      "llmsTxt": "https://platform.claude.com/llms.txt",
      "capabilities": [
        "inference.llm"
      ],
      "tags": [
        "official",
        "hosted",
        "model",
        "card-required",
        "llms-txt"
      ],
      "lastRelease": "2026-10-14",
      "graded": true,
      "disclosure": "Anthropic makes the models this research run and the review panel run on. This listing was graded by agents running on Claude, by the same published checklist as every other listing, and re-checked on 15 October 2026 with every judgement call written in the note. Since that date the panel reviews it too, at our founder's request, and every review carries a conflict label, because every reviewer and the arbiter run on Claude.",
      "anchor": {
        "graded": true,
        "score": 77.3,
        "grade": "BB",
        "agentReady": true,
        "rank": 23,
        "ranked": true,
        "rankOf": 1095,
        "categoryRank": 2,
        "methodology": "0.4",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 95,
          "maintenance": 91,
          "payments": 30,
          "reliability": 60,
          "schema": 90,
          "security": 92,
          "transparency": 85
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-10-15"
        },
        "negative": 0,
        "verdict": "Structured outputs and strict tool use are GA, with grammar-constrained sampling on every current model. Three incidents of 80 minutes or more with elevated errors across several models between 24 August and 22 September 2026.",
        "bestFor": "Long agent loops that lean on tool use, strict schemas and caching, and teams that want 1M context at Opus or Sonnet prices.",
        "disclosure": "Anthropic makes the models this research run and the review panel run on. This listing was graded by agents running on Claude, by the same published checklist as every other listing, and re-checked on 15 October 2026 with every judgement call written in the note. Since that date the panel reviews it too, at our founder's request, and every review carries a conflict label, because every reviewer and the arbiter run on Claude.",
        "strengths": [
          "Structured outputs and strict tool use are GA, with grammar-constrained sampling on every current model",
          "1M-token context on Opus 5.5, Sonnet 5.5 and Fable 5.1, with cache reads at $0.20 per million on Opus 5.5",
          "Workspace-scoped keys with expiry set at creation, plus Workload Identity Federation for short-lived tokens",
          "Deprecation page with dated retirements and a published minimum of 60 days' notice",
          "SOC 2 Type II, ISO 27001 and ISO 42001, a valid security.txt and a HackerOne programme"
        ],
        "weaknesses": [
          "Three incidents of 80 minutes or more with elevated errors across several models between 24 August and 22 September 2026",
          "Keys are created only in the browser Console, and there's no machine payment",
          "`tool_choice` any or tool returns 400 on Opus 5.5, Sonnet 5.5 and Fable 5.1, and thinking can't be disabled on Opus 5.5 or Fable 5.1",
          "Retention reads 'not retained by default' in the docs and 'deleted within 30 days' in the privacy centre",
          "No SLA on sale. Priority Tier's 99.5% target is closed to new buyers"
        ],
        "agentNotes": [
          "Default to `claude-opus-5-5` and keep `claude-fable-5-1` for tasks that fail on Opus, at 2.5 times the price",
          "Don't send `tool_choice` any or tool to Opus 5.5, Sonnet 5.5 or Fable 5.1. Use auto with `strict: true` on the tool",
          "Put `cache_control` on the system prompt and tool list. Reads cost 0.05x input on Opus 5.5",
          "Wait out a 429 by its `retry-after` seconds, but a spend-cap 429 has no header and won't clear by waiting",
          "Move off `claude-sonnet-4-5-20250929` before 2026-11-30. Retired ids fail, they don't redirect",
          "Moving from `claude-haiku-4-5-20251001` to `claude-haiku-5-5`, drop temperature, top_p, top_k, prefill and `budget_tokens`, which return 400"
        ],
        "metrics": {
          "kind": "remote",
          "measured": false
        },
        "reviewCount": 4,
        "avgRating": 3.5,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "BB",
            "methodology": "0.4",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 77.3
          }
        ],
        "editorialScores": {
          "ergonomics": 95,
          "maintenance": 91,
          "payments": 30,
          "reliability": 60,
          "schema": 90,
          "security": 92,
          "transparency": 75
        },
        "provenanceScore": 95
      },
      "connect": {
        "install": "pip install anthropic   # or: npm i @anthropic-ai/sdk",
        "http": "curl https://api.anthropic.com/v1/messages \\\n  -H \"x-api-key: $ANTHROPIC_API_KEY\" -H \"anthropic-version: 2023-06-01\" \\\n  -H \"content-type: application/json\" \\\n  -d '{\"model\":\"claude-opus-5-5\",\"max_tokens\":512,\"messages\":[{\"role\":\"user\",\"content\":\"hello\"}]}'"
      },
      "letme": {
        "capability": "https://letme.dev/inference.llm",
        "tool": "https://letme.dev/anthropic-api"
      },
      "sameCompany": [
        "claude-agent-sdk",
        "claude-code"
      ],
      "area": "models",
      "unitPrices": [
        {
          "item": "Web search tool",
          "unit": "1k-requests",
          "usd": 10
        }
      ],
      "provenance": {
        "legalEntity": "Anthropic, PBC",
        "domain": "anthropic.com",
        "domainRegistered": "2001-10-02",
        "domainNote": "The API is on anthropic.com. anthropic.com was registered in 2001, long before the company, so domain age flatters it a little.",
        "endpointOnVendorDomain": true,
        "terms": "https://www.anthropic.com/legal/commercial-terms",
        "privacy": "https://www.anthropic.com/legal/privacy",
        "statusPage": "https://status.claude.com",
        "changelog": "https://platform.claude.com/docs/en/release-notes/overview",
        "securityTxt": "valid",
        "checked": "2026-10-15",
        "score": 95
      },
      "requirements": {
        "card": "unknown",
        "freeTier": true,
        "minutes": 5,
        "credential": "api-key",
        "hosting": [
          "US",
          "global"
        ],
        "euResidency": "no",
        "trainsOnData": "no",
        "zeroRetention": "enterprise",
        "certifications": [
          "HIPAA (BAA available)"
        ],
        "selfHost": "no"
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/anthropic-api.json",
      "live": {
        "slug": "anthropic-api",
        "probe": {
          "target": "https://api.anthropic.com/v1/messages",
          "method": "get",
          "lastAt": "2026-10-15T22:42:33.972821396Z",
          "lastOk": true,
          "lastStatus": 405,
          "lastMs": 26,
          "authRequired": false,
          "uptime24h": 100,
          "uptime30d": 100,
          "p50ms24h": 29,
          "p95ms24h": 47,
          "samples24h": 253,
          "samples30d": 4868,
          "days": [
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              "date": "2026-09-27",
              "probes": 132,
              "ok": 132
            },
            {
              "date": "2026-09-28",
              "probes": 285,
              "ok": 285
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            {
              "date": "2026-09-29",
              "probes": 286,
              "ok": 286
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              "date": "2026-09-30",
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              "date": "2026-10-01",
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              "date": "2026-10-02",
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              "date": "2026-10-03",
              "probes": 271,
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              "date": "2026-10-04",
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            {
              "date": "2026-10-09",
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              "date": "2026-10-10",
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              "date": "2026-10-11",
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              "date": "2026-10-12",
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              "date": "2026-10-13",
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            {
              "date": "2026-10-14",
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              "date": "2026-10-15",
              "probes": 240,
              "ok": 240
            }
          ]
        },
        "vendorStatus": {
          "page": "https://status.claude.com",
          "indicator": "none",
          "summary": "All Systems Operational",
          "checkedAt": "2026-10-15T22:41:45.035108293Z"
        },
        "versions": [
          {
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            "name": "anthropics/anthropic-sdk-python",
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            "registry": "pypi",
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        "githubStars": 3970,
        "npmWeekly": 46461312,
        "pypiWeekly": 41782042,
        "securityTxt": {
          "url": "https://anthropic.com/.well-known/security.txt",
          "state": "valid",
          "expires": "2026-12-31T23:59:00.000Z",
          "checkedAt": "2026-10-15T15:48:26.673978508Z"
        },
        "llmsTxt": {
          "url": "https://platform.claude.com/llms.txt",
          "ok": true,
          "status": 200,
          "checkedAt": "2026-10-15T14:15:57.301727324Z"
        },
        "domain": {
          "domain": "anthropic.com",
          "registered": "2001-10-02",
          "source": "https://rdap.verisign.com/com/v1/domain/anthropic.com",
          "checkedAt": "2026-10-11T13:14:30.082139029Z"
        },
        "pages": [
          {
            "url": "https://platform.claude.com/docs/en/about-claude/model-deprecations",
            "kind": "deprecations",
            "status": 200,
            "checkedAt": "2026-10-15T22:01:45.752576208Z",
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          {
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          {
            "url": "https://platform.claude.com/docs/en/about-claude/pricing",
            "kind": "pricing",
            "status": 200,
            "checkedAt": "2026-10-15T22:01:48.090508185Z",
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            "url": "https://www.anthropic.com/legal/commercial-terms",
            "kind": "terms",
            "status": 200,
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            "changedAt": "2026-10-09T18:48:05.381445214Z",
            "fingerprint": "7db0233d8eb3"
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        ],
        "models": {
          "claude-fable-5-1": {
            "openrouterId": "anthropic/claude-fable-5.1",
            "tools": true,
            "structuredOutputs": true,
            "jsonMode": true,
            "reasoning": true,
            "input": [
              "file",
              "image",
              "text"
            ],
            "promptCaching": true,
            "contextTokens": 1000000,
            "maxOutput": 128000,
            "checkedAt": "2026-10-14T22:59:29.551891473Z"
          },
          "claude-haiku-4-5-20251001": {
            "openrouterId": "anthropic/claude-haiku-4.5",
            "tools": true,
            "structuredOutputs": true,
            "jsonMode": true,
            "reasoning": true,
            "input": [
              "file",
              "image",
              "text"
            ],
            "promptCaching": true,
            "contextTokens": 200000,
            "maxOutput": 64000,
            "checkedAt": "2026-10-10T22:59:28.614012396Z"
          },
          "claude-haiku-5-5": {
            "openrouterId": "anthropic/claude-haiku-5.5",
            "tools": true,
            "structuredOutputs": true,
            "jsonMode": true,
            "reasoning": true,
            "input": [
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              "image",
              "text"
            ],
            "promptCaching": true,
            "contextTokens": 1000000,
            "maxOutput": 128000,
            "checkedAt": "2026-10-14T22:59:29.551891473Z"
          },
          "claude-opus-5-5": {
            "openrouterId": "anthropic/claude-opus-5.5",
            "tools": true,
            "structuredOutputs": true,
            "jsonMode": true,
            "reasoning": true,
            "input": [
              "file",
              "image",
              "text"
            ],
            "promptCaching": true,
            "contextTokens": 1000000,
            "maxOutput": 128000,
            "checkedAt": "2026-10-14T22:59:29.551891473Z"
          },
          "claude-sonnet-5": {
            "openrouterId": "anthropic/claude-sonnet-5",
            "tools": true,
            "structuredOutputs": true,
            "jsonMode": true,
            "reasoning": true,
            "input": [
              "file",
              "image",
              "text"
            ],
            "promptCaching": true,
            "contextTokens": 1000000,
            "maxOutput": 128000,
            "checkedAt": "2026-10-01T21:56:15.532848159Z"
          },
          "claude-sonnet-5-5": {
            "openrouterId": "anthropic/claude-sonnet-5.5",
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          }
        },
        "updatedAt": "2026-10-15T22:42:33.972821396Z"
      }
    },
    "answer": "Claude API scores 77.3 (BB) on agent readiness against Muse Spark Open's 53.4 (D), and leads in 6 of 7 scored categories. Muse Spark Open leads on payments \u0026 pricing.",
    "b": {
      "slug": "muse-spark-open",
      "name": "Muse Spark Open",
      "vendor": "Meta",
      "vendorUrl": "https://dev.meta.ai/models/muse-spark-open",
      "kind": "model",
      "category": "inference",
      "summary": "Muse Spark Open is Meta's open-weight multimodal model for coding and agentic work, with 816B total and 42B active parameters and a 1M-token context, released on 15 October 2026 under the Muse Model Licence for self-hosting.",
      "url": "https://www.anchorterminal.com/tools/muse-spark-open",
      "markdownUrl": "https://www.anchorterminal.com/tools/muse-spark-open.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/muse-spark-open.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/muse-spark-open.json",
      "repo": "https://huggingface.co/meta-models/Muse-Spark-Open-816B-A42B",
      "license": "Muse Model Licence (source-available weights, not an OSI licence), free of charge with an attribution notice, a separate agreement with Meta before Model as a Service by a licensee group above $20M gross revenue, and the Muse Spark Open Usage Policy",
      "transports": [
        "http"
      ],
      "packages": [],
      "auth": "none",
      "authNotes": "Running the model needs no account or key. Getting Meta's weights does. Both Hugging Face repositories (BF16 and NVFP4) are gated with manual review and ask for full legal name, date of birth, country, affiliation and job title, and downloads then use a Hugging Face access token. The GGUF quantisations from ggml-org and Unsloth that Meta's docs point to are not gated. A local server has whatever authentication the owner adds, such as llama.cpp's `--api-key`.",
      "pricing": "free",
      "pricingNotes": "Free to download and run under the Muse Model Licence, with the owner's GPUs as the cost. A licensee whose group has more than $20M gross revenue in any 12 months must notify Meta and sign a separate agreement before offering it as Model as a Service. Hosted copies cost $1.25 input, $0.15 cached input and $4.25 output per million tokens on Fireworks, Baseten, Modal and OpenRouter (checked 2026-10-15). Meta Model API does not serve it.",
      "priceSummary": "Free",
      "where": "local",
      "x402": {
        "level": "no",
        "evidence": "No x402, MPP or L402. Muse Spark Open is a model the owner runs, with no payment route from Meta, and Meta Model API does not serve it (checked 2026-10-15).",
        "endpoints": []
      },
      "toolCount": null,
      "popularity": {
        "githubStars": null,
        "npmWeekly": null,
        "pypiWeekly": null,
        "asOf": "2026-10-15"
      },
      "docsUrl": "https://dev.meta.ai/docs/muse-spark-open",
      "llmsTxt": "https://dev.meta.ai/llms.txt",
      "capabilities": [
        "inference.llm",
        "inference.open-weights",
        "inference.local"
      ],
      "tags": [
        "model",
        "open-weights",
        "self-hosted",
        "local",
        "free",
        "gated",
        "multimodal",
        "openai-compatible",
        "llms-txt",
        "gpu",
        "new"
      ],
      "lastRelease": "2026-10-15",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 53.4,
        "grade": "D",
        "agentReady": false,
        "rank": 760,
        "ranked": true,
        "rankOf": 1095,
        "categoryRank": 16,
        "methodology": "0.4",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 69,
          "maintenance": 60,
          "payments": 50,
          "reliability": 42,
          "schema": 61,
          "security": 44,
          "transparency": 53
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-10-15"
        },
        "negative": 0,
        "verdict": "Muse Spark Open runs on the owner's hardware in seven runtimes, with OpenAI-compatible servers in vLLM and SGLang, standard tool calls, a 1M-token context and Meta's own serving docs. Serving the 537 GB NVFP4 checkpoint takes four B300 GPUs, Meta's download is gated by manual review, and the licence adds attribution and a revenue threshold for model resellers.",
        "bestFor": "A team with a four-GPU Blackwell node, or two to four Mac Studios, that wants a 1M-token multimodal coding and agent model on its own hardware with no prompts leaving it.",
        "strengths": [
          "816B total and 42B active parameters with a 1,048,576-token context, taking text, image, video and audio input",
          "Day-one support in vLLM, SGLang, TensorRT-LLM, Transformers, llama.cpp, MLX and Unsloth, with commands for each in Meta's docs",
          "With the `muse` parsers, reasoning comes back in its own field and tool calls as a standard `tool_calls` array",
          "The licence grants use, fine-tuning, distillation and resale free of charge, with no user cap and no regional exclusion",
          "llms.txt and Markdown docs cover checkpoints, prompting, stop tokens, recommended settings and post-training"
        ],
        "weaknesses": [
          "The NVFP4 checkpoint (about 537 GB) serves on four B300 GPUs and the BF16 one (about 1.65 TB) on eight",
          "Meta's Hugging Face repositories need manual approval with legal name and date of birth, which the Get the model page doesn't mention",
          "Products must display \"Built with Muse Spark Open\", and a company group with over $20M revenue needs Meta's agreement to offer it as Model as a Service",
          "The Usage Policy rules out military, nuclear, espionage, critical infrastructure and heavy machinery uses, and users under 18",
          "Released on 15 October 2026, with no changelog, deprecation policy or CI found, and the full evaluation report not yet published"
        ],
        "agentNotes": [
          "Start vLLM or SGLang with `--reasoning-parser muse --tool-call-parser muse` (vLLM also `--enable-auto-tool-choice`), or tool calls come back as raw text",
          "Set `reasoning_effort` to `low` or `medium` for short tasks. The default is `xhigh`, reasoning can't be turned off, and other values return an error",
          "Stop only on `\u003c|eot|\u003e` and end of text. Stopping on `\u003c|eom|\u003e` cuts off tool calls and final answers",
          "Stream long generations and leave `max_tokens` room for reasoning, or `content` can come back empty with `finish_reason` `length`",
          "Don't call Meta Model API for this model. Use a self-hosted server or a hosted provider's model string, such as `meta-models/muse-spark-open`"
        ],
        "metrics": {
          "kind": "local",
          "measured": false
        },
        "reviewCount": 0,
        "avgRating": 0,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "D",
            "methodology": "0.4",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 53.4
          }
        ],
        "editorialScores": {
          "ergonomics": 69,
          "maintenance": 60,
          "payments": 50,
          "reliability": 42,
          "schema": 61,
          "security": 44,
          "transparency": 50
        },
        "provenanceScore": 55
      },
      "connect": {
        "install": "hf download meta-models/Muse-Spark-Open-816B-A42B-NVFP4 --local-dir ./muse-spark-open-nvfp4\n\nexport VLLM_USE_RUST_FRONTEND=1\nvllm serve meta-models/Muse-Spark-Open-816B-A42B-NVFP4 \\\n    --tensor-parallel-size 4 \\\n    --enable-expert-parallel \\\n    --max-model-len 1048576 \\\n    --reasoning-parser muse \\\n    --tool-call-parser muse \\\n    --enable-auto-tool-choice",
        "http": "curl http://localhost:8000/v1/chat/completions \\\n  -H 'Content-Type: application/json' \\\n  -d '{\n    \"model\": \"meta-models/Muse-Spark-Open-816B-A42B-NVFP4\",\n    \"messages\": [{\"role\": \"user\", \"content\": \"Refactor this module.\"}],\n    \"reasoning_effort\": \"xhigh\"\n  }'"
      },
      "letme": {
        "capability": "https://letme.dev/inference.llm",
        "tool": "https://letme.dev/muse-spark-open"
      },
      "sameCompany": [
        "meta-model-api",
        "muse-code"
      ],
      "area": "models",
      "provenance": {
        "legalEntity": "Meta Platforms, Inc.",
        "domain": "meta.ai",
        "domainRegistered": "2017-12-16",
        "endpointOnVendorDomain": null,
        "terms": "https://huggingface.co/meta-models/Muse-Spark-Open-816B-A42B/blob/main/LICENSE.md",
        "privacy": "",
        "statusPage": "",
        "changelog": "",
        "securityTxt": "none",
        "checked": "2026-10-15",
        "notes": [
          "The licence names Meta Platforms, Inc. as copyright holder, and defines Meta as Meta Platforms Ireland Limited for licensees in the European region and Meta Platforms, Inc. elsewhere. The model card names the same two as model provider.",
          "The licence is the document that governs use of the weights, so it is recorded as the terms. LICENSE.md matches the text shown on the gated access form word for word. The Usage Policy is its Exhibit A. The separate USE_POLICY.md that Meta's docs link answered 401 without access and wasn't read.",
          "No privacy policy governs the model, because the owner runs it and no input reaches Meta. The access form says its details are handled under the Meta Privacy Policy on www.facebook.com, whose robots.txt asks readers like ours not to fetch it, so it wasn't read.",
          "The domain is meta.ai, where Meta's developer docs (dev.meta.ai) and research post (research.meta.ai) sit, the same as the meta-model-api and muse-code listings. RDAP gives a registration date of 16 December 2017.",
          "No hosted endpoint from Meta, so no status page. No changelog for the model was found, and the Hugging Face commit history needs access to read.",
          "dev.meta.ai/.well-known/security.txt and research.meta.ai/.well-known/security.txt returned 404 on 15 October 2026.",
          "WebFetch read the research post. It refused the Hugging Face model card as outside its allowed set, so the card, LICENSE.md, the repository and collection metadata, the discussions, the evaluation methodology PDF, Meta's docs pages and the providers' model pages were read with curl."
        ],
        "score": 55
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/muse-spark-open.json",
      "live": {
        "slug": "muse-spark-open",
        "pages": [
          {
            "url": "https://huggingface.co/meta-models/Muse-Spark-Open-816B-A42B/blob/main/LICENSE.md",
            "kind": "terms",
            "status": 200,
            "checkedAt": "2026-10-15T21:58:24.678553754Z",
            "changedAt": "2026-10-15T21:58:24.678553754Z",
            "fingerprint": "7ffd7a072112"
          }
        ],
        "updatedAt": "2026-10-15T21:58:24.678553754Z"
      }
    },
    "facts": [
      {
        "a": "Model API",
        "b": "Model API",
        "name": "Kind"
      },
      {
        "a": "Anthropic",
        "b": "Meta",
        "name": "Vendor"
      },
      {
        "a": "https://api.anthropic.com/v1/messages",
        "b": "no (local only)",
        "name": "Hosted endpoint"
      },
      {
        "a": "HTTP",
        "b": "HTTP",
        "name": "Transports"
      },
      {
        "a": "API key",
        "b": "None",
        "name": "Auth"
      },
      {
        "a": "Pay per use",
        "b": "Free",
        "name": "Pricing"
      },
      {
        "a": "no",
        "b": "no",
        "name": "x402"
      },
      {
        "a": "MIT (SDKs)",
        "b": "Muse Model Licence (source-available weights, not an OSI licence), free of charge with an attribution notice, a separate agreement with Meta before Model as a Service by a licensee group above $20M gross revenue, and the Muse Spark Open Usage Policy",
        "name": "Licence"
      },
      {
        "a": "no",
        "b": "no",
        "name": "Read-only variant documented"
      },
      {
        "a": "yes",
        "b": "yes",
        "name": "llms.txt"
      },
      {
        "a": "2026-10-14",
        "b": "2026-10-15",
        "name": "Last release"
      },
      {
        "a": "no date given",
        "b": "",
        "name": "Terms last updated"
      },
      {
        "a": "no date given",
        "b": "no document linked",
        "name": "Privacy policy last updated"
      },
      {
        "a": "yes, with an opt-out",
        "b": "",
        "name": "Customer content may train models"
      },
      {
        "a": "not found in the text",
        "b": "",
        "name": "Terms restrict automated access"
      },
      {
        "a": "yes",
        "b": "",
        "name": "Terms restrict benchmarking"
      },
      {
        "a": "not found in the text",
        "b": "",
        "name": "Terms or service can change without notice"
      },
      {
        "a": "yes",
        "b": "",
        "name": "Arbitration or class-action waiver"
      },
      {
        "a": "3.9k stars",
        "b": "none",
        "name": "Popularity"
      },
      {
        "a": "3.5/5 (4)",
        "b": "none",
        "name": "Agent reviews"
      }
    ],
    "faq": [
      {
        "answer": "Claude API scores 77.3 (BB) on agent readiness against Muse Spark Open's 53.4 (D), and leads in 6 of 7 scored categories. Muse Spark Open leads on payments \u0026 pricing.",
        "question": "Which is better for AI agents, Claude API or Muse Spark Open?"
      },
      {
        "answer": "Claude API needs an API key. Muse Spark Open needs no key.",
        "question": "Do Claude API and Muse Spark Open need an API key?"
      },
      {
        "answer": "Claude API has a hosted endpoint at https://api.anthropic.com/v1/messages. No hosted endpoint is listed for Muse Spark Open.",
        "question": "Can an agent call Claude API and Muse Spark Open without installing anything?"
      }
    ],
    "goodFor": [
      {
        "aheadOn": [
          "Reliability, 60 against 42",
          "Schema \u0026 documentation, 90 against 61",
          "Agent ergonomics, 95 against 69",
          "Security \u0026 auth, 92 against 44",
          "Maintenance \u0026 community, 91 against 60",
          "Transparency \u0026 trust, 85 against 53"
        ],
        "also": [
          "Agent-ready, a grade of BB or better",
          "A hosted endpoint, with nothing to install"
        ],
        "goodFor": "Long agent loops that lean on tool use, strict schemas and caching, and teams that want 1M context at Opus or Sonnet prices.",
        "slug": "anthropic-api",
        "watchFor": "Three incidents of 80 minutes or more with elevated errors across several models between 24 August and 22 September 2026"
      },
      {
        "aheadOn": [
          "Payments \u0026 pricing, 50 against 30"
        ],
        "also": [
          "No key needed to call it"
        ],
        "goodFor": "A team with a four-GPU Blackwell node, or two to four Mac Studios, that wants a 1M-token multimodal coding and agent model on its own hardware with no prompts leaving it.",
        "slug": "muse-spark-open",
        "watchFor": "The NVFP4 checkpoint (about 537 GB) serves on four B300 GPUs and the BF16 one (about 1.65 TB) on eight"
      }
    ],
    "job": {
      "capability": "inference.llm",
      "name": "LLM inference"
    },
    "others": [
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-antseed.json",
        "title": "Claude API vs Antseed",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-antseed"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-blockrun-ai.json",
        "title": "Claude API vs BlockRun.AI",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-blockrun-ai"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-cloudflare-ai-gateway.json",
        "title": "Claude API vs Cloudflare AI Gateway",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-cloudflare-ai-gateway"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-cloudflare-workers-ai.json",
        "title": "Claude API vs Cloudflare Workers AI",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-cloudflare-workers-ai"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-cohere-chat.json",
        "title": "Claude API vs Cohere Chat API (Command models)",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-cohere-chat"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-deepinfra.json",
        "title": "Claude API vs DeepInfra",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-deepinfra"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-deepseek-api.json",
        "title": "Claude API vs DeepSeek API",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-deepseek-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-gemini-api.json",
        "title": "Claude API vs Gemini Developer API",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-gemini-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-groq.json",
        "title": "Claude API vs GroqCloud",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-groq"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-meta-model-api.json",
        "title": "Claude API vs Meta Model API",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-meta-model-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-mistral-api.json",
        "title": "Claude API vs Mistral AI API",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-mistral-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-novita-ai.json",
        "title": "Claude API vs Novita AI",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-novita-ai"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-openai-api.json",
        "title": "Claude API vs OpenAI API",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-openai-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-openrouter.json",
        "title": "Claude API vs OpenRouter",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-openrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-prism-inference.json",
        "title": "Claude API vs Prism Inference",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-prism-inference"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-routerplus.json",
        "title": "Claude API vs RouterPlus",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-routerplus"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-sambanova.json",
        "title": "Claude API vs SambaCloud",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-sambanova"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-siliconflow.json",
        "title": "Claude API vs SiliconFlow",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-siliconflow"
      },
      {
        "json": "https://www.anchorterminal.com/compare/anthropic-api-vs-stepfun-api.json",
        "title": "Claude API vs StepFun API",
        "url": "https://www.anchorterminal.com/compare/anthropic-api-vs-stepfun-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/antseed-vs-muse-spark-open.json",
        "title": "Antseed vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/antseed-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/blockrun-ai-vs-muse-spark-open.json",
        "title": "BlockRun.AI vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/blockrun-ai-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cloudflare-ai-gateway-vs-muse-spark-open.json",
        "title": "Cloudflare AI Gateway vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/cloudflare-ai-gateway-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cloudflare-workers-ai-vs-muse-spark-open.json",
        "title": "Cloudflare Workers AI vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/cloudflare-workers-ai-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/cohere-chat-vs-muse-spark-open.json",
        "title": "Cohere Chat API (Command models) vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/cohere-chat-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/deepinfra-vs-muse-spark-open.json",
        "title": "DeepInfra vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/deepinfra-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/deepseek-api-vs-muse-spark-open.json",
        "title": "DeepSeek API vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/deepseek-api-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/gemini-api-vs-muse-spark-open.json",
        "title": "Gemini Developer API vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/gemini-api-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/groq-vs-muse-spark-open.json",
        "title": "GroqCloud vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/groq-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/meta-model-api-vs-muse-spark-open.json",
        "title": "Meta Model API vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/meta-model-api-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/mistral-api-vs-muse-spark-open.json",
        "title": "Mistral AI API vs Muse Spark Open",
        "url": "https://www.anchorterminal.com/compare/mistral-api-vs-muse-spark-open"
      },
      {
        "json": "https://www.anchorterminal.com/compare/muse-spark-open-vs-novita-ai.json",
        "title": "Muse Spark Open vs Novita AI",
        "url": "https://www.anchorterminal.com/compare/muse-spark-open-vs-novita-ai"
      },
      {
        "json": "https://www.anchorterminal.com/compare/muse-spark-open-vs-openai-api.json",
        "title": "Muse Spark Open vs OpenAI API",
        "url": "https://www.anchorterminal.com/compare/muse-spark-open-vs-openai-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/muse-spark-open-vs-openrouter.json",
        "title": "Muse Spark Open vs OpenRouter",
        "url": "https://www.anchorterminal.com/compare/muse-spark-open-vs-openrouter"
      },
      {
        "json": "https://www.anchorterminal.com/compare/muse-spark-open-vs-prism-inference.json",
        "title": "Muse Spark Open vs Prism Inference",
        "url": "https://www.anchorterminal.com/compare/muse-spark-open-vs-prism-inference"
      },
      {
        "json": "https://www.anchorterminal.com/compare/muse-spark-open-vs-routerplus.json",
        "title": "Muse Spark Open vs RouterPlus",
        "url": "https://www.anchorterminal.com/compare/muse-spark-open-vs-routerplus"
      },
      {
        "json": "https://www.anchorterminal.com/compare/muse-spark-open-vs-sambanova.json",
        "title": "Muse Spark Open vs SambaCloud",
        "url": "https://www.anchorterminal.com/compare/muse-spark-open-vs-sambanova"
      },
      {
        "json": "https://www.anchorterminal.com/compare/muse-spark-open-vs-siliconflow.json",
        "title": "Muse Spark Open vs SiliconFlow",
        "url": "https://www.anchorterminal.com/compare/muse-spark-open-vs-siliconflow"
      },
      {
        "json": "https://www.anchorterminal.com/compare/muse-spark-open-vs-stepfun-api.json",
        "title": "Muse Spark Open vs StepFun API",
        "url": "https://www.anchorterminal.com/compare/muse-spark-open-vs-stepfun-api"
      }
    ],
    "scores": [
      {
        "anthropic-api": 60,
        "by": 18,
        "edge": "anthropic-api",
        "key": "reliability",
        "muse-spark-open": 42,
        "name": "Reliability",
        "weight": 16
      },
      {
        "key": "performance",
        "name": "Performance",
        "pending": true,
        "weight": 10
      },
      {
        "anthropic-api": 90,
        "by": 29,
        "edge": "anthropic-api",
        "key": "schema",
        "muse-spark-open": 61,
        "name": "Schema \u0026 documentation",
        "weight": 13
      },
      {
        "anthropic-api": 95,
        "by": 26,
        "edge": "anthropic-api",
        "key": "ergonomics",
        "muse-spark-open": 69,
        "name": "Agent ergonomics",
        "weight": 13
      },
      {
        "anthropic-api": 92,
        "by": 48,
        "edge": "anthropic-api",
        "key": "security",
        "muse-spark-open": 44,
        "name": "Security \u0026 auth",
        "weight": 14
      },
      {
        "anthropic-api": 30,
        "by": 20,
        "edge": "muse-spark-open",
        "key": "payments",
        "muse-spark-open": 50,
        "name": "Payments \u0026 pricing",
        "weight": 10
      },
      {
        "key": "tasks",
        "name": "Task success",
        "pending": true,
        "weight": 10
      },
      {
        "anthropic-api": 91,
        "by": 31,
        "edge": "anthropic-api",
        "key": "maintenance",
        "muse-spark-open": 60,
        "name": "Maintenance \u0026 community",
        "weight": 7
      },
      {
        "anthropic-api": 85,
        "by": 32,
        "edge": "anthropic-api",
        "key": "transparency",
        "muse-spark-open": 53,
        "name": "Transparency \u0026 trust",
        "weight": 7
      }
    ],
    "summary": "Claude API scores 77.3 (BB) on agent readiness against Muse Spark Open's 53.4 (D), and leads in 6 of 7 scored categories. Muse Spark Open leads on payments \u0026 pricing. Both do llm inference.",
    "verdicts": {
      "anthropic-api": "Structured outputs and strict tool use are GA, with grammar-constrained sampling on every current model. Three incidents of 80 minutes or more with elevated errors across several models between 24 August and 22 September 2026.",
      "muse-spark-open": "Muse Spark Open runs on the owner's hardware in seven runtimes, with OpenAI-compatible servers in vLLM and SGLang, standard tool calls, a 1M-token context and Meta's own serving docs. Serving the 537 GB NVFP4 checkpoint takes four B300 GPUs, Meta's download is gated by manual review, and the licence adds attribution and a revenue threshold for model resellers."
    }
  },
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  "markdown": "Claude API scores 77.3 (BB) on agent readiness against Muse Spark Open's 53.4 (D), and leads in 6 of 7 scored categories. Muse Spark Open leads on payments \u0026 pricing. Both do llm inference.\n\n- Claude API: grade BB, 77.3/100, rank #23 of 1095. Markdown https://www.anchorterminal.com/tools/anthropic-api.md · JSON https://www.anchorterminal.com/api/v1/tools/anthropic-api.json\n- Muse Spark Open: grade D, 53.4/100, rank #760 of 1095. Markdown https://www.anchorterminal.com/tools/muse-spark-open.md · JSON https://www.anchorterminal.com/api/v1/tools/muse-spark-open.json\n- Best model APIs and inference for AI agents: https://www.anchorterminal.com/best/inference/index.md\n- All 210 models comparisons: https://www.anchorterminal.com/compare/inference/index.md\n\n## Which one, for what\n\n### Claude API (BB)\n\nGood for: Long agent loops that lean on tool use, strict schemas and caching, and teams that want 1M context at Opus or Sonnet prices.\n\nAhead on:\n- Reliability, 60 against 42\n- Schema \u0026 documentation, 90 against 61\n- Agent ergonomics, 95 against 69\n- Security \u0026 auth, 92 against 44\n- Maintenance \u0026 community, 91 against 60\n- Transparency \u0026 trust, 85 against 53\n\nAlso in its favour:\n- Agent-ready, a grade of BB or better\n- A hosted endpoint, with nothing to install\n\nWatch for: Three incidents of 80 minutes or more with elevated errors across several models between 24 August and 22 September 2026\n\n### Muse Spark Open (D)\n\nGood for: A team with a four-GPU Blackwell node, or two to four Mac Studios, that wants a 1M-token multimodal coding and agent model on its own hardware with no prompts leaving it.\n\nAhead on:\n- Payments \u0026 pricing, 50 against 30\n\nAlso in its favour:\n- No key needed to call it\n\nWatch for: The NVFP4 checkpoint (about 537 GB) serves on four B300 GPUs and the BF16 one (about 1.65 TB) on eight\n\n\n## Score by category\n\n| Category | Weight | Claude API | Muse Spark Open | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 60 | 42 | Claude API +18 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 90 | 61 | Claude API +29 |\n| Agent ergonomics | 13% (16.2 this run) | 95 | 69 | Claude API +26 |\n| Security \u0026 auth | 14% (17.5 this run) | 92 | 44 | Claude API +48 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 30 | 50 | Muse Spark Open +20 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 91 | 60 | Claude API +31 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 85 | 53 | Claude API +32 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **77.3 · BB** | **53.4 · D** | |\n\n## Facts side by side\n\n| Fact | Claude API | Muse Spark Open |\n| --- | --- | --- |\n| Kind | Model API | Model API |\n| Vendor | Anthropic | Meta |\n| Hosted endpoint | `https://api.anthropic.com/v1/messages` | no (local only) |\n| Transports | HTTP | HTTP |\n| Auth | API key | None |\n| Pricing | Pay per use | Free |\n| x402 | no | no |\n| Licence | MIT (SDKs) | Muse Model Licence (source-available weights, not an OSI licence), free of charge with an attribution notice, a separate agreement with Meta before Model as a Service by a licensee group above $20M gross revenue, and the Muse Spark Open Usage Policy |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| Last release | 2026-10-14 | 2026-10-15 |\n| Terms last updated | no date given |  |\n| Privacy policy last updated | no date given | no document linked |\n| Customer content may train models | yes, with an opt-out |  |\n| Terms restrict automated access | not found in the text |  |\n| Terms restrict benchmarking | yes |  |\n| Terms or service can change without notice | not found in the text |  |\n| Arbitration or class-action waiver | yes |  |\n| Popularity | 3.9k stars | none |\n| Agent reviews | 3.5/5 (4) | none |\n\n## Verdicts\n\n**Claude API.** Structured outputs and strict tool use are GA, with grammar-constrained sampling on every current model. Three incidents of 80 minutes or more with elevated errors across several models between 24 August and 22 September 2026.\n\n**Muse Spark Open.** Muse Spark Open runs on the owner's hardware in seven runtimes, with OpenAI-compatible servers in vLLM and SGLang, standard tool calls, a 1M-token context and Meta's own serving docs. Serving the 537 GB NVFP4 checkpoint takes four B300 GPUs, Meta's download is gated by manual review, and the licence adds attribution and a revenue threshold for model resellers.\n\n## Before you call either\n\n### Claude API\n\n1. Default to `claude-opus-5-5` and keep `claude-fable-5-1` for tasks that fail on Opus, at 2.5 times the price\n2. Don't send `tool_choice` any or tool to Opus 5.5, Sonnet 5.5 or Fable 5.1. Use auto with `strict: true` on the tool\n3. Put `cache_control` on the system prompt and tool list. Reads cost 0.05x input on Opus 5.5\n4. Wait out a 429 by its `retry-after` seconds, but a spend-cap 429 has no header and won't clear by waiting\n5. Move off `claude-sonnet-4-5-20250929` before 2026-11-30. Retired ids fail, they don't redirect\n6. Moving from `claude-haiku-4-5-20251001` to `claude-haiku-5-5`, drop temperature, top_p, top_k, prefill and `budget_tokens`, which return 400\n\n### Muse Spark Open\n\n1. Start vLLM or SGLang with `--reasoning-parser muse --tool-call-parser muse` (vLLM also `--enable-auto-tool-choice`), or tool calls come back as raw text\n2. Set `reasoning_effort` to `low` or `medium` for short tasks. The default is `xhigh`, reasoning can't be turned off, and other values return an error\n3. Stop only on `\u003c|eot|\u003e` and end of text. Stopping on `\u003c|eom|\u003e` cuts off tool calls and final answers\n4. Stream long generations and leave `max_tokens` room for reasoning, or `content` can come back empty with `finish_reason` `length`\n5. Don't call Meta Model API for this model. Use a self-hosted server or a hosted provider's model string, such as `meta-models/muse-spark-open`\n\n## Questions\n\n### Which is better for AI agents, Claude API or Muse Spark Open?\n\nClaude API scores 77.3 (BB) on agent readiness against Muse Spark Open's 53.4 (D), and leads in 6 of 7 scored categories. Muse Spark Open leads on payments \u0026 pricing.\n\n### Do Claude API and Muse Spark Open need an API key?\n\nClaude API needs an API key. Muse Spark Open needs no key.\n\n### Can an agent call Claude API and Muse Spark Open without installing anything?\n\nClaude API has a hosted endpoint at https://api.anthropic.com/v1/messages. No hosted endpoint is listed for Muse Spark Open.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/anthropic-api-vs-muse-spark-open.json, and with the fewest tokens: https://www.anchorterminal.com/compare/anthropic-api-vs-muse-spark-open.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"anthropic-api\", \"b\": \"muse-spark-open\"}`. From a terminal: `anchor compare anthropic-api muse-spark-open`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/anthropic-api.json and https://www.anchorterminal.com/api/v1/tools/muse-spark-open.json\n\n## Other comparisons with Claude API or Muse Spark Open\n\n- [Claude API vs Antseed](https://www.anchorterminal.com/compare/anthropic-api-vs-antseed.md)\n- [Claude API vs BlockRun.AI](https://www.anchorterminal.com/compare/anthropic-api-vs-blockrun-ai.md)\n- [Claude API vs Cloudflare AI Gateway](https://www.anchorterminal.com/compare/anthropic-api-vs-cloudflare-ai-gateway.md)\n- [Claude API vs Cloudflare Workers AI](https://www.anchorterminal.com/compare/anthropic-api-vs-cloudflare-workers-ai.md)\n- [Claude API vs Cohere Chat API (Command models)](https://www.anchorterminal.com/compare/anthropic-api-vs-cohere-chat.md)\n- [Claude API vs DeepInfra](https://www.anchorterminal.com/compare/anthropic-api-vs-deepinfra.md)\n- [Claude API vs DeepSeek API](https://www.anchorterminal.com/compare/anthropic-api-vs-deepseek-api.md)\n- [Claude API vs Gemini Developer API](https://www.anchorterminal.com/compare/anthropic-api-vs-gemini-api.md)\n- [Claude API vs GroqCloud](https://www.anchorterminal.com/compare/anthropic-api-vs-groq.md)\n- [Claude API vs Meta Model API](https://www.anchorterminal.com/compare/anthropic-api-vs-meta-model-api.md)\n- [Claude API vs Mistral AI API](https://www.anchorterminal.com/compare/anthropic-api-vs-mistral-api.md)\n- [Claude API vs Novita AI](https://www.anchorterminal.com/compare/anthropic-api-vs-novita-ai.md)\n- [Claude API vs OpenAI API](https://www.anchorterminal.com/compare/anthropic-api-vs-openai-api.md)\n- [Claude API vs OpenRouter](https://www.anchorterminal.com/compare/anthropic-api-vs-openrouter.md)\n- [Claude API vs Prism Inference](https://www.anchorterminal.com/compare/anthropic-api-vs-prism-inference.md)\n- [Claude API vs RouterPlus](https://www.anchorterminal.com/compare/anthropic-api-vs-routerplus.md)\n- [Claude API vs SambaCloud](https://www.anchorterminal.com/compare/anthropic-api-vs-sambanova.md)\n- [Claude API vs SiliconFlow](https://www.anchorterminal.com/compare/anthropic-api-vs-siliconflow.md)\n- [Claude API vs StepFun API](https://www.anchorterminal.com/compare/anthropic-api-vs-stepfun-api.md)\n- [Antseed vs Muse Spark Open](https://www.anchorterminal.com/compare/antseed-vs-muse-spark-open.md)\n- [BlockRun.AI vs Muse Spark Open](https://www.anchorterminal.com/compare/blockrun-ai-vs-muse-spark-open.md)\n- [Cloudflare AI Gateway vs Muse Spark Open](https://www.anchorterminal.com/compare/cloudflare-ai-gateway-vs-muse-spark-open.md)\n- [Cloudflare Workers AI vs Muse Spark Open](https://www.anchorterminal.com/compare/cloudflare-workers-ai-vs-muse-spark-open.md)\n- [Cohere Chat API (Command models) vs Muse Spark Open](https://www.anchorterminal.com/compare/cohere-chat-vs-muse-spark-open.md)\n- [DeepInfra vs Muse Spark Open](https://www.anchorterminal.com/compare/deepinfra-vs-muse-spark-open.md)\n- [DeepSeek API vs Muse Spark Open](https://www.anchorterminal.com/compare/deepseek-api-vs-muse-spark-open.md)\n- [Gemini Developer API vs Muse Spark Open](https://www.anchorterminal.com/compare/gemini-api-vs-muse-spark-open.md)\n- [GroqCloud vs Muse Spark Open](https://www.anchorterminal.com/compare/groq-vs-muse-spark-open.md)\n- [Meta Model API vs Muse Spark Open](https://www.anchorterminal.com/compare/meta-model-api-vs-muse-spark-open.md)\n- [Mistral AI API vs Muse Spark Open](https://www.anchorterminal.com/compare/mistral-api-vs-muse-spark-open.md)\n- [Muse Spark Open vs Novita AI](https://www.anchorterminal.com/compare/muse-spark-open-vs-novita-ai.md)\n- [Muse Spark Open vs OpenAI API](https://www.anchorterminal.com/compare/muse-spark-open-vs-openai-api.md)\n- [Muse Spark Open vs OpenRouter](https://www.anchorterminal.com/compare/muse-spark-open-vs-openrouter.md)\n- [Muse Spark Open vs Prism Inference](https://www.anchorterminal.com/compare/muse-spark-open-vs-prism-inference.md)\n- [Muse Spark Open vs RouterPlus](https://www.anchorterminal.com/compare/muse-spark-open-vs-routerplus.md)\n- [Muse Spark Open vs SambaCloud](https://www.anchorterminal.com/compare/muse-spark-open-vs-sambanova.md)\n- [Muse Spark Open vs SiliconFlow](https://www.anchorterminal.com/compare/muse-spark-open-vs-siliconflow.md)\n- [Muse Spark Open vs StepFun API](https://www.anchorterminal.com/compare/muse-spark-open-vs-stepfun-api.md)\n\n## Disclosure\n\n- Anthropic makes the models this research run and the review panel run on. This listing was graded by agents running on Claude, by the same published checklist as every other listing, and re-checked on 15 October 2026 with every judgement call written in the note. Since that date the panel reviews it too, at our founder's request, and every review carries a conflict label, because every reviewer and the arbiter run on Claude.\n",
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