{"uid":"cap_Oa8wxmZwW0hqhBoBxg8Vo","slug":"cortexcloud-messages-api-openai-compatible-x402-edcfa201","name":"CortexCloud Messages API (OpenAI-compatible, x402)","description":"OpenAI-compatible AI and data API for agents. Pay per call in USDC on Base via x402 — no API keys, no subscriptions, no lock-in.","url":"https://api.cortexcloud.org/x402/v1/messages","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"model":{"type":"string"},"messages":{"type":"array","items":{"type":"object"}},"max_tokens":{"type":"integer"}}},"responseSchema":{"type":"object","format":"application/json","example":{}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_4_QnLCD-4Il7x5nBv4Ilb","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Sends chat completion messages to an OpenAI-compatible LLM endpoint, paying per call in USDC on Base via x402 with no API key required.","exampleAgentPrompt":"Using the CortexCloud pay-per-call AI API, send the message 'Explain the concept of compound interest in two sentences' to gpt-3.5-turbo with a max of 150 tokens, paying in USDC — no API key needed.","exampleUseCases":[{"title":"Keyless LLM for autonomous agent pipeline","prompt":"I'm building an autonomous agent that needs to call an LLM without managing API keys or subscriptions — use CortexCloud to send 'Summarize this support ticket: customer reports login failure after password reset' to gpt-3.5-turbo with max 200 tokens, paying per call in USDC."},{"title":"One-off AI answer with crypto micropayment","prompt":"Ask the CortexCloud AI: 'What are three best practices for writing unit tests in Python?' using gpt-4 with max 300 tokens — I want to pay per call in USDC on Base, no account needed."},{"title":"On-demand content generation without subscription","prompt":"Use the pay-per-call Cortex AI to generate a short product description for 'a reusable silicone food storage bag' — send it as a chat message to gpt-3.5-turbo with max 100 tokens and pay the $0.005 USDC fee automatically."}],"resultDescription":"Returns an OpenAI-compatible chat completion JSON object containing the AI-generated assistant message, model used, token usage statistics, and finish reason. The response mirrors the standard OpenAI /v1/chat/completions response format.","failureModes":["Insufficient USDC balance on Base — payment fails with 402 Payment Required","Invalid or unsupported model name — returns 400 or model error","Malformed messages array — returns validation error","max_tokens exceeds model context limit — returns parameter error","Network or service downtime — returns 5xx error","Payment transaction not confirmed on Base — request not processed"],"whenToPreferThis":"Choose this endpoint when you need OpenAI-compatible LLM inference without committing to an API key or subscription, especially in agentic or automated pipelines that already handle x402/USDC micropayments on Base. It is ideal for pay-as-you-go usage patterns, wallet-native AI agents, or scenarios where avoiding vendor lock-in and account management overhead is a priority.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T00:50:21.606Z","isFirstParty":false}