{"uid":"cap_5_KJZATMtRbrNvUBH0y9l","slug":"model-access-gateway-claude-opus-4-5-via-x402-4f0fccd6","name":"Model Access Gateway – Claude Opus 4.5 via x402","description":"LLM inference API: OpenAI-compatible chat completions for 136 AI models (Claude, GPT, Gemini, Grok, DeepSeek, Qwen, Kimi, GLM), paid per call in USDC on Base with x402. No account, no API key, automatic refund if the model fails.","url":"https://agent402-arb.rosariovitale0096.workers.dev/llm/claude-opus-5.5?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"model":{"type":"string","description":"Optional: fixed by the route (anthropic/claude-opus-5.5)"},"tools":{"type":"array"},"stream":{"type":"boolean","description":"true: server-sent events after payment"},"messages":{"type":"array","items":{"type":"object","required":["role"],"properties":{"role":{"enum":["system","user","assistant","tool","developer"],"type":"string"},"content":{"type":["string","array","null"]}}},"minItems":1},"max_tokens":{"type":"integer","maximum":16384,"minimum":1,"description":"Optional, default 4096"},"temperature":{"type":"number","maximum":2,"minimum":0},"response_format":{"type":"object"}}},"responseSchema":{"type":"json","example":{"id":"chatcmpl-7f3c2a91","model":"anthropic/claude-opus-5.5","usage":{"total_tokens":10,"prompt_tokens":9,"completion_tokens":1},"object":"chat.completion","choices":[{"index":0,"message":{"role":"assistant","content":"OK"},"finish_reason":"stop"}],"created":1791979200}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.0014","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":"$0.0014/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.0014","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.0014","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_yFTzqR2Mmd9pXpAQIKjPD","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.0014","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Proxies OpenAI-compatible chat completion requests to Anthropic Claude Opus 4.5, billed per request in USDC on Base via x402 protocol — no API key required.","exampleAgentPrompt":"Send this conversation to Claude Opus 4.5 and get a response: the system prompt says 'You are a helpful assistant' and the user asked 'What is the capital of France?' — pay per request using USDC on Base.","exampleUseCases":[{"title":"Permissionless LLM for autonomous agent","prompt":"I'm building an AI agent that needs to call Claude Opus for complex reasoning steps, but I don't want to manage API keys — can you route my chat messages to Claude Opus 4.5 and just charge me per call in USDC?"},{"title":"One-off Claude Opus inference task","prompt":"I need Claude Opus to analyze this legal clause and summarize the key obligations: 'The licensee shall indemnify...' — just pay the per-request fee in USDC and give me the response."},{"title":"Multi-model comparison via unified gateway","prompt":"Run my prompt through Claude Opus 4.5 using the x402 gateway so I can compare its answer to GPT-4o — the prompt is: 'Explain the trolley problem and its ethical implications in three sentences.'"}],"resultDescription":"Returns an OpenAI-compatible chat.completion JSON object including the assistant's message content, model name (anthropic/claude-opus-5.5), token usage (prompt, completion, total), finish reason, and a completion ID and timestamp. The response mirrors the standard OpenAI /v1/chat/completions format for easy drop-in integration.","failureModes":["Payment not provided or insufficient USDC balance — gateway returns HTTP 402 Payment Required","Malformed request body (missing required 'input' field or invalid bodyType) — returns 400 Bad Request","Model temporarily unavailable upstream at Anthropic — returns 503 or upstream error","Rate limiting on the worker — returns 429 Too Many Requests","Invalid or expired x402 payment token — returns 402 with rejection details"],"whenToPreferThis":"Choose this endpoint when you need Claude Opus 4.5 specifically (Anthropic's highest-capability model) without holding an Anthropic API key, and you want to pay per request in USDC on Base using the x402 protocol. It is ideal for autonomous agents operating in crypto-native environments, one-off inference tasks, or multi-model pipelines where account management overhead is undesirable. Prefer alternatives if you need streaming responses, batch inference at scale, or are already holding Anthropic or OpenAI API keys with volume discounts.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-18T06:47:31.382Z","isFirstParty":false,"canonicalSlug":"model-access-gateway-claude-opus-4-5-via-x402-4f0fccd6"}