{"uid":"cap_swsmw0JBwtX5j1DB5jvJV","slug":"openai-gpt-5-1-chat-completions-x402-usdc-05587275","name":"OpenAI GPT-5.1 Chat Completions (x402/USDC)","description":"gpt-5.1: OpenAI GPT 5.1 chat completions, paid per call in USDC. Per 1M tokens in/out: Flex (default) 0.625/5.0, Standard 1.25/10.0, Fast 2.5/20.0; pick with service_tier. Plus $0.0005 (Base) or $0.0005 (Solana) per call; the quote charges input plus 10% of max_tokens. Levels: none, low, medium, high (model gpt-5.1:<level>). Empty answers are free. Rates: https://openai.mm.family/x402/pricing","url":"https://openai.mm.family/x402/v1/models/gpt-5.1/chat/completions?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"model":{"enum":["gpt-5.1","gpt-5.1:none","gpt-5.1:low","gpt-5.1:medium","gpt-5.1:high"],"type":"string"},"tools":{"type":"array"},"stream":{"type":"boolean"},"messages":{"type":"array","items":{"type":"object","required":["role","content"],"properties":{"role":{"type":"string"},"content":{"type":"string"}}}},"max_tokens":{"type":"integer"},"service_tier":{"enum":["flex","default","standard","auto","fast","priority"],"type":"string"},"response_format":{"type":"object"},"reasoning_effort":{"type":"string"}}},"responseSchema":{"type":"json","example":{"id":"chatcmpl-x","model":"gpt-5.1","usage":{"total_tokens":9,"prompt_tokens":8,"completion_tokens":1},"object":"chat.completion","choices":[{"index":0,"message":{"role":"assistant","content":"Hello","refusal":null},"finish_reason":"stop"}],"service_tier":"flex"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_V4oUDXg3vTrJQfCW5m0ci","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Runs OpenAI GPT-5.1 chat completions via a pay-per-call USDC gateway, with selectable service tiers (Flex, Standard, Fast) and reasoning levels","exampleAgentPrompt":"Using GPT-5.1 on standard tier with high reasoning, answer this multi-step logic problem for me: 'A farmer has 17 sheep, all but 9 die — how many are left?' and limit the response to 200 tokens.","exampleUseCases":[{"title":"Complex reasoning with high effort","prompt":"I need GPT-5.1 to work through a difficult legal clause analysis for me — use the high reasoning level and standard service tier, and keep the output under 500 tokens."},{"title":"Fast low-cost question answering","prompt":"Use GPT-5.1 on flex tier to quickly answer: what are the top 3 differences between REST and GraphQL? Keep it concise, max 150 tokens."},{"title":"Agentic tool-calling workflow","prompt":"Set up a GPT-5.1 chat completion on standard tier with my custom tools list — I want the model to decide whether to call my 'search_web' tool or answer directly based on the user's question about current stock prices."}],"resultDescription":"Returns a JSON chat completion object containing the assistant's reply message, token usage breakdown (prompt, completion, total), finish reason, model name, service tier used, and a unique completion ID. Empty completions (e.g. for quota checks) are returned free of charge.","failureModes":["Insufficient USDC balance — payment fails before inference runs","max_tokens too low — model truncates output at limit with finish_reason='length'","Invalid model enum value — 400 error if model string not in allowed list","Rate limit exceeded on chosen service tier — 429 response","Malformed messages array (missing role or content) — 422 validation error","Network timeout on fast/flex tier during high load"],"whenToPreferThis":"Choose this endpoint when you need GPT-5.1 specifically (vs GPT-5-nano or GPT-5.2) and want pay-per-call USDC billing without an OpenAI subscription. Prefer the Flex tier for cost-sensitive batch workloads, Standard for balanced throughput, and Fast for latency-critical agent loops. Use the reasoning level suffix (none/low/medium/high) when you need to control compute depth for complex tasks.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-02T12:41:37.028Z","isFirstParty":false,"canonicalSlug":"openai-gpt-5-1-chat-completions-x402-usdc-05587275"}