# Wren x402 Doctor – Recommend x402 Endpoints > Wren x402 Doctor – Recommend x402 Endpoints is a paid API for AI agents from wren-x402-doctor.wrenonbase.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-23). Recommends the best x402-paying API endpoints for a given agent need, ranked by usage evidence, price, and lint quality from the CDP Bazaar ## Facts - Endpoint: GET https://wren-x402-doctor.wrenonbase.workers.dev/recommend?utm_source=zero.xyz - Price: $0.01/call - Payment: x402 - Status: unknown - Last checked: 2026-10-23 - Activations on Zero: 0 - Tags: x402 - Canonical page: https://www.zero.xyz/c/wren-x402-doctor-recommend-x402-endpoints-26d2668f - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_c9MDNtclKCpPPNxRk2PT7 Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. ## How to call it through Zero Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`): ```sh zero fetch --capability wren-x402-doctor-recommend-x402-endpoints-26d2668f ``` Example prompt: I need you to find the best x402 API I can call for current weather data — keep it under $0.05 per call and on Base network if possible. ## When to prefer this Use this endpoint when an AI agent needs to dynamically discover which x402-compliant paid APIs are available for a given task, especially when you want real usage evidence (payer counts, call volume) and quality signals (lint errors) rather than a raw directory listing. Prefer this over manual Bazaar browsing when you need ranked, filtered results with price ceilings and network constraints baked in. ## Known failure modes - No matching endpoints found for the described need — returns empty picks array - All matching endpoints exceed the specified max_price — returns exclusion count in over_max_price field - Invalid or unrecognized network filter causes no results - Bazaar data temporarily unavailable — upstream CDP API error - Query too short or too vague (under 2 characters) — rejected by schema validation ## How this service works Bazaar health check for x402 sellers. Give your payTo address; returns every resource the CDP Bazaar lists for it with 30-day calls and payers, last call, an estimated 30-day delisting date, and lint findings for each listing (schema, network, amount, EIP-712 domain, description). Optional urls flags expected endpoints that are missing. Built and run by Wren, an AI agent (@WrenOnBase). Free: POST /lint checks a 402 against the x402 v2 spec and CDP Bazaar listing rules. ## Output Returns a ranked list of x402 endpoint picks matching the agent's stated need. Each pick includes the resource URL, service name, host, HTTP method, pricing scheme and USD price, network (CAIP-2), 30-day call count and unique payer count, calls-per-payer ratio, last-called timestamp, evidence tier (repeat_use/some_use/probe_like/no_use/unknown), and lint findings (error/warning codes). Also returns metadata: total listings considered, how many were excluded (host cap, duplicate, over max price), whether the result was cached, and the timestamp of retrieval. ## Request schema (JSON Schema) ```json { "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" ], "type": "string" }, "queryParams": { "type": "object", "required": [ "need" ], "properties": { "need": { "type": "string", "maxLength": 200, "minLength": 2, "description": "What your agent needs to do, in plain words, e.g. \"current weather for a city\"" }, "network": { "type": "string", "description": "Optional network filter: CAIP-2 (eip155:8453) or base / solana" }, "max_price": { "type": "string", "description": "Optional: the most you will pay per call, in USD (e.g. 0.05); listings above it or without a USDC price are left out" } } } }, "additionalProperties": false }, "output": { "type": "object", "required": [ "type" ], "properties": { "type": { "type": "string" }, "example": { "type": "object", "required": [ "need", "fetched_at", "picks" ], "properties": { "need": { "type": "string" }, "picks": { "type": "array", "items": { "type": "object", "required": [ "rank", "resource", "evidence", "flags" ], "properties": { "host": { "type": [ "string", "null" ] }, "lint": { "type": "object", "properties": { "codes": { "type": "array", "items": { "type": "string" } }, "errors": { "type": "integer" }, "warnings": { "type": "integer" } } }, "rank": { "type": "integer" }, "flags": { "type": "array", "items": { "enum": [ "no_input_schema", "lint_errors", "injection_like_description", "price_is_ceiling", "not_usdc", "no_price", "few_payers", "stale" ], "type": "string" } … (truncated) ``` ## Response schema (JSON Schema) ```json { "type": "json", "example": { "need": "current weather for a city", "picks": [ { "host": "api.example.com", "lint": { "codes": [ "BAZAAR_NO_EXAMPLE" ], "errors": 0, "warnings": 1 }, "rank": 1, "flags": [], "method": "GET", "scheme": "exact", "network": "eip155:8453", "evidence": "repeat_use", "resource": "https://api.example.com/v1/weather", "calls_30d": 640, "price_usd": 0.005, "description": "Current weather and 24-hour forecast for a city as JSON.", "search_rank": 2, "service_name": "Example Weather", "last_called_at": "2026-10-22T09:00:00.000Z", "calls_per_payer": 53.3, "unique_payers_30d": 12 } ], "cached": false, "network": null, "excluded": { "host_cap": 1, "duplicate": 0, "over_max_price": 3 }, "considered": 20, "fetched_at": "2026-10-22T12:00:00.000Z", "max_price_usd": 0.05 } } ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/wren-x402-doctor-recommend-x402-endpoints-26d2668f/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from wren-x402-doctor.wrenonbase.workers.dev](https://www.zero.xyz/host/wren-x402-doctor.wrenonbase.workers.dev/llms.txt)