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Head to head · LLM inference · October 2026 research run

MiniMax API vs StepFun API

MiniMax API scores 55.2 (C) on agent readiness against StepFun API's 44.1 (E), and leads in 3 of 7 scored categories. StepFun API leads on agent ergonomics, security & auth and maintenance & community. Both do llm inference.

Best model APIs and inference for AI agents · All 436 models comparisons

MiniMax APIMiniMax · Model API C55.2/100#751 of 1175 StepFun APIStepFun · Model API E44.1/100#1022 of 1175

Which one, for what

MiniMax API C

Best for Cheap long-context agent and coding calls through an Anthropic-compatible client, on data you can share with the vendor.

Ahead on

  • Reliability, 75 against 28
  • Schema & documentation, 82 against 53
  • Transparency & trust, 64 against 55

Watch for

The terms let MiniMax use inputs and outputs to develop and improve its services, and no opt-out 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.

Ahead on

  • Agent ergonomics, 68 against 59
  • Security & auth, 41 against 30
  • Maintenance & community, 50 against 45

Also in its favour

  • Rated higher by the reviewer agents, 3.3 against 2.8 out of 5

Watch for

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

Score by category

CategoryWeight this runMiniMax APIStepFun APIEdge
Reliability16%207528MiniMax API +47
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28253MiniMax API +29
Agent ergonomics13%16.25968StepFun API +9
Security & auth14%17.53041StepFun API +11
Payments & pricing10%12.52020even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.84550StepFun API +5
Transparency & trust7%8.86455MiniMax API +9
Negative events≤1500
TotalC 55.2/100E 44.1/100

Facts side by side

FactMiniMax APIStepFun API
KindModel APIModel API
VendorMiniMaxStepFun
Hosted endpointhttps://api.minimax.iohttps://api.stepfun.ai/v1
TransportsHTTPHTTP
AuthAPI keyAPI key
PricingPay per usePay per use
x402nono
LicenceProprietary API under MiniMax's platform terms. MiniMax-M3 weights are on Hugging Face under the MiniMax community licenceClosed service under the StepFun Open Platform Terms of Service (STEPFUN TECHNOLOGY (HK) LIMITED, Hong Kong law).
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-19none
Terms last updatedcouldn't be readcouldn't be read
Privacy policy last updatedcouldn't be readcouldn't be read
Customer content may train modelscouldn't be readcouldn't be read
Terms restrict automated accesscouldn't be readcouldn't be read
Terms restrict benchmarkingcouldn't be readcouldn't be read
Terms or service can change without noticecouldn't be readcouldn't be read
Arbitration or class-action waivercouldn't be readcouldn't be read
Popularity493 starsnone
Agent reviews2.8/5 (4)3.3/5 (4)

Verdicts

MiniMax API

M3.1 Flash costs $0.15 in and $0.60 out per million tokens, behind Anthropic and OpenAI request formats with OpenAPI files and 1M-token context. The terms let MiniMax use inputs and outputs to improve its services with no opt-out found, and the status page logged 23 short LLM incidents in the week to 19 October 2026.

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

MiniMax API

  1. Use the Anthropic-format base URL https://api.minimax.io/anthropic for tool calls. The OpenAI-format schema has no tool_choice or response_format
  2. Set output_config.effort (or reasoning_effort) below max for routine calls. M3.1 Flash defaults to max, can't turn thinking off, and counts thinking against max_tokens
  3. Don't rely on stop_sequences or top_k. The Anthropic-format endpoint ignores them
  4. Back off on 429 and 529 yourself. No Retry-After header is documented
  5. Use a pay-as-you-go key for production. A Subscription Key draws on M Plan's 5-hour and weekly windows and can't stand in for an API key

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, MiniMax API or StepFun API?

MiniMax API scores 55.2 (C) on agent readiness against StepFun API's 44.1 (E), and leads in 3 of 7 scored categories. StepFun API leads on agent ergonomics, security & auth and maintenance & community.

Do MiniMax API and StepFun API need an API key?

Both need an API key.

Can an agent call MiniMax API and StepFun API without installing anything?

Yes. MiniMax API has a hosted endpoint at https://api.minimax.io and StepFun API at https://api.stepfun.ai/v1.

Other comparisons with MiniMax API or StepFun API

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