{"uid":"cap_JGxBh6iPDwfMJayVeBVFY","slug":"api-the402-ai-aa99fe88","name":"the402.ai Thread Message Sender","description":"Send thread message (free with API key)","url":"https://api.the402.ai/v1/threads/thread_f4a7d2a2575b4beb/messages","method":"POST","headers":{},"bodySchema":{"type":"object","required":["id"],"properties":{"id":{"type":"string"}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"settled","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"down","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_DwnY7GaO25FzHapQ2qFpm","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Posts a new message to a specific thread on the the402.ai platform using an API key for free access","exampleAgentPrompt":"Send the message 'Hello, can you summarize the latest project updates?' to thread thread_f4a7d2a2575b4beb on the402.ai.","exampleUseCases":null,"resultDescription":"Returns confirmation of the message being posted to the thread, typically including a message ID, the thread ID, content echoed back, and a timestamp indicating when the message was created.","failureModes":["Invalid or missing API key returns 401 unauthorized","Non-existent thread ID returns 404 not found","Empty or malformed message body returns 400 bad request","Rate limit exceeded returns 429 too many requests","Payment or quota issues may return 402 payment required despite free tier claim"],"whenToPreferThis":"Use this endpoint when you need to programmatically post messages into a specific the402.ai thread, particularly when operating with an API key for free-tier access. Prefer this over paid alternatives when your use case fits the free-with-API-key tier and you already have a valid thread ID on the platform.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T12:28:01.800Z","isFirstParty":false}