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Head to head · LLM inference · October 2026 research run

Meta Model API vs StepFun API

Meta Model API scores 52.2 (D) on agent readiness against StepFun API's 44.1 (E), and leads in 4 of 7 scored categories. Both do llm inference.

Best model APIs and inference for AI agents · All 171 models comparisons

Meta Model APIMeta · Model API D52.2/100#757 of 993 StepFun APIStepFun · Model API E44.1/100#905 of 993

Which one, for what

Meta Model API D

Best for Long-running agent and coding work over text, images, video, audio and PDFs with a 1M-token context, where training must stay off by default.

Ahead on

  • Reliability, 40 against 28
  • Schema & documentation, 60 against 53
  • Agent ergonomics, 75 against 68
  • Security & auth, 64 against 41

Watch for

Muse Wonder is labelled a preview, and no deprecation policy or notice period was found

StepFun API E

Best for Long-context agent and coding work over text, screenshots and video at a low per-token price, where a preview model is acceptable.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

Step 5 Preview is labelled a preview, and no release date or support commitment was found

Score by category

CategoryWeight this runMeta Model APIStepFun APIEdge
Reliability16%204028Meta Model API +12
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26053Meta Model API +7
Agent ergonomics13%16.27568Meta Model API +7
Security & auth14%17.56441Meta Model API +23
Payments & pricing10%12.52020even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.84650StepFun API +4
Transparency & trust7%8.85255StepFun API +3
Negative events≤1500
TotalD 52.2/100E 44.1/100

Facts side by side

FactMeta Model APIStepFun API
KindModel APIModel API
VendorMetaStepFun
Hosted endpointhttps://api.meta.ai/v1https://api.stepfun.ai/v1
TransportsHTTPHTTP
AuthAPI keyAPI key
PricingPay per usePay per use
x402nono
LicenceClosed service under the Meta Model API Terms of Service (last updated 9 October 2026), with Meta Platforms, Inc., or Meta Platforms Ireland Limited in the European Region, as the contracting party.Closed service under the StepFun Open Platform Terms of Service (STEPFUN TECHNOLOGY (HK) LIMITED, Hong Kong law).
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-12none
Terms last updatedcouldn't be read
Privacy policy last updatedcouldn't be readcouldn't be read
Customer content may train modelscouldn't be read
Terms restrict automated accesscouldn't be read
Terms restrict benchmarkingcouldn't be read
Terms or service can change without noticecouldn't be read
Arbitration or class-action waivercouldn't be read

Verdicts

Meta Model API

Meta Model API serves Muse Wonder, in preview since 12 October 2026, and Muse Spark with 1M-token context, constrained JSON Schema output, automatic prompt caching and per-token prices published without a login. Standard-mode content is not used for training. There's no free allowance, status history, OpenAPI file, deprecation policy or way to force a tool call.

StepFun API

StepFun's API serves Step 5 Preview with a 1M-token context, video input, strict JSON Schema output and published per-token prices, documented in Markdown with an llms.txt. The model is a preview with no release date found, there's no free allowance or SLA, and the terms and privacy policy leave room to train on customer data.

Before you call either

Meta Model API

  1. Use muse-wonder-1.0 for long multi-step work and muse-spark-1.3 for cheaper, high-volume calls. Both take the same requests
  2. Keep personal or confidential data away from -contributor model IDs. Meta may train on that content
  3. Honour Retry-After on 429 and 503, which is 60 seconds for service_overloaded, and check GET https://api.meta.ai/v1/status, which needs no key
  4. Pass the key to the OpenAI SDK explicitly or set OPENAI_API_KEY. The SDK doesn't read MODEL_API_KEY
  5. Leave tool_choice at auto. The docs say none and required are not supported

StepFun API

  1. Set max_tokens yourself. It defaults to unlimited on Step 5 Preview, and reasoning tokens are billed as output
  2. Use response_format with type: json_schema and strict: true when the shape matters. JSON Mode alone isn't schema-checked
  3. Back off and retry on 429, 500, 503 and 504. The docs give no Retry-After header or backoff schedule
  4. Expect HTTP 451 or finish_reason: content_filter when content fails StepFun's review, and don't retry the same input
  5. Use api.stepfun.ai for the international platform. api.stepfun.com is the China platform with yuan pricing

Questions

Which is better for AI agents, Meta Model API or StepFun API?

Meta Model API scores 52.2 (D) on agent readiness against StepFun API's 44.1 (E), and leads in 4 of 7 scored categories.

Do Meta Model API and StepFun API need an API key?

Both need an API key.

Can an agent call Meta Model API and StepFun API without installing anything?

Yes. Meta Model API has a hosted endpoint at https://api.meta.ai/v1 and StepFun API at https://api.stepfun.ai/v1.

Other comparisons with Meta Model API or StepFun API

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