{"uid":"cap_hG6QP8LCjoxs8cq3--WAP","slug":"openai-gpt-5-6-luna-long-272k-context-chat-completions-4fa305a7","name":"OpenAI GPT-5.6 Luna Long (>272K context) Chat Completions","description":"gpt-5.6-luna-long: OpenAI GPT 5.6 Luna (>272K input tokens) chat completions, paid per call in USDC. Per 1M tokens in/out: Flex (default) 0.2/0.9, Standard 0.4/1.8, Fast 0.8/3.6; 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, xhigh (model gpt-5.6-luna-long:<level>). Empty answers are free. Rates: https://openai.mm.family/x402/pricing","url":"https://openai.mm.family/x402/v1/models/gpt-5.6-luna-long/chat/completions?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"model":{"enum":["gpt-5.6-luna-long","gpt-5.6-luna-long:none","gpt-5.6-luna-long:low","gpt-5.6-luna-long:medium","gpt-5.6-luna-long:high","gpt-5.6-luna-long:xhigh"],"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-5.6-luna-long","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_DUvdzRg-_D0vlyuCc_GfL","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":"Provides paid chat completions using OpenAI GPT-5.6 Luna model with extended context (>272K input tokens), billed per call in USDC via x402 protocol","exampleAgentPrompt":"Use GPT-5.6 Luna (long context) to analyze this 400-page legal document I'm pasting in and summarize the key liability clauses — use the standard service tier and allow up to 2000 output tokens.","exampleUseCases":[{"title":"Long document summarization with Luna","prompt":"I've got a massive 300-page research report — can you send the full text to GPT-5.6 Luna long context and ask it to produce a concise executive summary? Use the flex tier and cap the output at 1500 tokens."},{"title":"Extended conversation reasoning agent","prompt":"I need to continue a very long multi-turn conversation with a GPT-5.6 Luna model — the history is huge, well over 300K tokens. Please use the high reasoning level and fast service tier so I get a quick, high-quality reply."},{"title":"Code review across a large codebase","prompt":"Can you send the entire contents of my project's source files — probably around 350K tokens worth — to GPT-5.6 Luna long context and ask it to identify security vulnerabilities? Use the xhigh quality level and standard tier."}],"resultDescription":"Returns a chat completion object in OpenAI-compatible format, including the assistant's reply message, finish reason (e.g. 'stop'), token usage breakdown (prompt, completion, total), model name, and service tier used. Empty answers are provided free of charge.","failureModes":["Insufficient USDC balance or failed x402 payment results in 402 Payment Required","Exceeding model's maximum context length returns a context length error","Invalid model variant string returns a 400 validation error","service_tier enum mismatch (e.g. unsupported value) returns 400","max_tokens set too high relative to remaining context causes truncation or error","Rate limiting at the provider level may return 429 Too Many Requests"],"whenToPreferThis":"Choose this endpoint when your input conversation or document exceeds 272K tokens and you need GPT-5.6 Luna's specific capability profile. Prefer over the standard gpt-5.6-luna (short context) endpoint when inputs are very large. Prefer over gpt-6-astra-long if cost is a priority and GPT-5.6 quality suffices. Use when you need x402 USDC micropayment billing and want to select between flex, standard, or fast inference tiers.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-02T12:42:41.157Z","isFirstParty":false,"canonicalSlug":"openai-gpt-5-6-luna-long-272k-context-chat-completions-4fa305a7"}