{"uid":"cap_LyujQoSqQyYGE4FA4fMN2","slug":"gpt-5-3-codex-chat-completions-via-x402-get-e6bf8eae","name":"GPT-5.3 Codex Chat Completions via x402 (GET)","description":"GPT-5.6 Luna API Base USDC and OpenAI-compatible x402 chat: one request for $0.00293, paid by browser wallet or a quote-first agent fallback.","url":"https://gpt55.558686.xyz/v1/chat/completions/gpt-5.3-codex","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"pathParams":{"type":"object","additionalProperties":true},"queryParams":{"type":"object","properties":{"q":{"type":"string"},"input":{"type":"string"},"model":{"enum":["gpt-5.6-sol","gpt-5.6","gpt-5.6-luna","gpt-5.6-terra","gpt-5.5","gpt-5.3-codex","gpt-5.4"],"type":"string"},"prompt":{"type":"string"},"system":{"type":"string"},"message":{"type":"string"},"max_tokens":{"type":"integer","maximum":128000,"minimum":1},"system_prompt":{"type":"string"},"max_output_tokens":{"type":"integer","maximum":128000,"minimum":1}},"additionalProperties":true}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","required":["id","object","model","choices"],"properties":{"id":{"type":"string"},"model":{"type":"string"},"usage":{"type":"object"},"object":{"type":"string"},"choices":{"type":"array"}},"additionalProperties":true}}}}},"responseSchema":{"type":"json","example":{"id":"chatcmpl_example","model":"gpt-5.6-luna","usage":{"total_tokens":44,"prompt_tokens":32,"completion_tokens":12},"object":"chat.completion","choices":[{"index":0,"message":{"role":"assistant","content":"A concise answer from GPT-5.5."},"finish_reason":"stop"}]}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.007472","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":"$0.007472/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.007472","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.007472","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_EUhMtW0huuS3DJp3epknR","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.007472","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Generates GPT-5.3-Codex coding-oriented chat completions via GET query parameters, paid per-request with USDC over x402.","exampleAgentPrompt":"Can you use the GPT-5.3 Codex model to help me plan and write a Python patch for rate-limiting middleware — keep the response under 2000 tokens?","exampleUseCases":[{"title":"Generate code for REST API","prompt":"Use the GPT-5.3 Codex model to write a Node.js REST API endpoint that handles user authentication with JWT tokens — pay per call with USDC and keep the output concise."},{"title":"Plan a software refactor","prompt":"I need to refactor a legacy Python monolith into microservices — can you use GPT-5.3 Codex to create a structured patch plan with file-by-file changes and keep it under 3000 tokens?"},{"title":"Fix a bug in code","prompt":"There's a bug in my TypeScript async function where promises aren't being awaited correctly — can you ask the GPT-5.3 Codex model to diagnose and fix it, using a pay-per-call USDC request?"}],"resultDescription":"Returns an OpenAI-compatible chat completion object containing an id, model name, choices array with assistant message content (typically code or structured development output), and a usage object with token counts. Actual output length depends on upstream availability, request parameters, and account policy up to 128000 tokens.","failureModes":["Payment not provided or insufficient — 402 Payment Required returned","Input exceeds 700000 character limit — request rejected","Upstream model unavailable — 503 or timeout error","Invalid model enum value in query param — 400 Bad Request","max_tokens out of range (must be 1–128000) — validation error","Missing required 'input' query parameter — 400 error"],"whenToPreferThis":"Choose this endpoint when you need coding-oriented GPT chat completions (patch planning, code generation, structured dev output) via a simple GET request with x402 USDC micropayment on Base or Solana, without needing a long-lived API key. Ideal for AI agents that support x402 payment flows and want Codex-class output on a pay-per-call basis.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T00:43:55.617Z","isFirstParty":false}