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x402AI Ask Endpoint
x402
x402AI Ask Endpoint is a paid API for AI agents from api.x402ai.dev, paid per call via x402, $0.04/call, status unknown (last checked 2026-10-02).
Answers a natural language question via AI inference, gated by a $0.04 USDC micropayment on Base mainnet using the x402 protocol.
Price / call$0.04
Success—
StatusUnknown
How this service works
Single-turn question answering from a small local LLM (qwen3.5 2B). Best for general knowledge, definitions and simple reasoning. POST JSON {"input": string}, up to 3000 characters; returns {answer, model, elapsed_ms}. Answers are brief (2-3 sentences). Typically 5-15 s. Known limits: no web access, no memory between calls, and it can hallucinate or be wrong on recent events and obscure facts. Verify anything important.
Output
Returns a JSON object with an 'answer' field containing the AI-generated text response to the submitted question.
Example use cases
On-chain AI factual lookup
“Use the x402AI pay-per-query service to answer this for me: what is the current circulating supply mechanism for Ethereum after the merge?”
Quick AI explanation for developer
“I need a concise explanation of how the ERC-4337 account abstraction standard works — can you query x402AI with that question and pay the micropayment fee?”
Autonomous agent knowledge query
“My agent needs to answer 'what are the trade-offs between optimistic rollups and zk-rollups?' — send that question to the x402AI inference endpoint and get the answer back.”
Technical details
Endpoint
POSThttps://api.x402ai.dev/api/ask?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need pay-per-query AI inference without a subscription, specifically within an agent or application that already handles x402 micropayment flows on Base mainnet. Ideal for autonomous agents that should pay for knowledge lookups on-chain with USDC, or for developers building crypto-native apps that want metered AI access at $0.04 per call.
Side effects
- Payment failure: insufficient USDC balance or x402 payment not accepted, resulting in 402 Payment Required response
- Invalid input: missing or empty 'input' field returns a validation error
- Inference timeout: AI model takes too long and returns a timeout or 500 error
- Network/mainnet issues: Base mainnet congestion or RPC errors causing payment verification failure
- Malformed request: non-string input type causes schema validation error
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | string | Question to ask |
Output
Schema · Response
| Field | Type | Description |
|---|---|---|
| answerrequired | string |
Tags
x402
Reviews
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