# Animica x402 API Search Index > Animica x402 API Search Index is a paid API for AI agents from animica.dev, paid per call via x402, $0.0018/call, status unknown (last checked 2026-09-15). Search a live index of x402 pay-per-call API endpoints by capability, parameter, schema field, or network to find callable services matching your query. ## Facts - Endpoint: POST https://animica.dev/x402/index - Price: $0.0018/call - Payment: x402 - Status: unknown - Last checked: 2026-09-15 - Activations on Zero: 0 - Tags: x402 - Canonical page: https://www.zero.xyz/c/animica-x402-api-search-index-223038ab - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_0Zd3aDSwibrCOgAsg0Dx2 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 animica-x402-api-search-index-223038ab -d '' ``` Example prompt: Search the Animica x402 API index for endpoints related to 'ERC20 token balance' — give me up to 10 results priced at $0.01 or less, and only show ones that are directly callable. ## When to prefer this Use this endpoint when an AI agent needs to dynamically discover other x402 pay-per-call API services by capability, parameter name, schema field, or blockchain network — especially when you want BM25-ranked results filtered by price or callability. Prefer this over manually browsing x402scan or hardcoding endpoint URLs when building agent pipelines that need to self-configure their tool set at runtime. ## Known failure modes - Query string missing or empty — may return empty results or error - limit out of range (must be 1–25) — may return default of 10 or validation error - max_price set to 0 or negative — likely returns no results - No matching endpoints in index — returns count 0 and empty results array - Index temporarily unavailable — service error response - Payment not settled via x402 — 402 Payment Required response before results are returned ## How this service works Full-text search over what machine-payable services actually publish — their descriptions, input schemas, parameter names, prices and settlement networks — across ~18,000 x402 endpoints. Built from their own payment challenges, which a general crawler discards as a dead page: ask for a parameter name, a schema field or a network and you match services whose one-line blurb never mentions it. Filter by price ceiling, by whether the service publishes a call spec, and by payment protocol. Every response states how many documents were searched and how stale the oldest is, because an index that will not tell you its size is asking to be trusted about the one thing you cannot check. Ranked by BM25 — no model, so the same query ranks the same way twice. If the index is empty or nothing matches, you are NOT charged. ## Output Returns a JSON object with the total count of matched endpoints, corpus metadata (document count, last build time), applied filters, BM25 relevance-ranked results array (each with URL, host, rank, score, title, snippet, callability flag, price in USD, HTTP method, payment protocol, and indexed timestamp), query execution time in milliseconds, and search timestamp. ## Request schema (JSON Schema) ```json { "type": "object", "properties": { "limit": { "type": "integer", "description": "results to return, 1..25 (default 10)" }, "query": { "type": "string", "description": "words to match: a capability, a parameter name, a schema field, a network" }, "max_price": { "type": "number", "description": "only services at or under this price in USD" }, "callable_only": { "type": "boolean", "description": "only services that publish a call spec" } } } ``` ## Response schema (JSON Schema) ```json { "type": "json", "example": { "count": 3, "query": "wallet_address erc20 balance", "corpus": { "sources": { "x402": 17987 }, "documents": 17987, "last_build": "2026-08-22T01:26:16.570Z", "oldest_document_age_seconds": 454 }, "filters": { "max_price": 0.01 }, "matched": 38, "ranking": "bm25(title x8, description x4, content x1) — deterministic, no model", "results": [ { "url": "https://signals.edge.report/v1/erc20-balance", "host": "signals.edge.report", "rank": 1, "score": 20.116, "title": "signals.edge.report/v1/erc20-balance", "snippet": "Get ERC20 token balance for any wallet and token contract on Base (or Ethereum). Returns balance, decimals, and symbol via balanceOf. Use for live … ", "callable": false, "price_usd": 0.001, "indexed_at": "2026-08-22T01:26:14.000Z", "http_method": "GET", "payment_protocol": "x402" }, { "url": "https://a2a.elonsusk.com/x402/data.evm.erc20_balance", "host": "a2a.elonsusk.com", "rank": 2, "score": 19.8317, "title": "a2a.elonsusk.com/x402/data.evm.erc20_balance", "snippet": "ERC-20 token balance of an address, auto-scaled by decimals, Base/Ethereum.\na2a.elonsusk.com/x402/data.evm.erc20_balance\neip155:8453\nUSD … ", "callable": false, "price_usd": 0.002, "indexed_at": "2026-08-22T01:26:16.000Z", "http_method": "POST", "payment_protocol": "x402" }, { "url": "https://api.x402node.dev/chain/balance", "host": "api.x402node.dev", "rank": 3, "score": 19.7807, "title": "api.x402node.dev/chain/balance", "snippet": "Native coin balance for any address on Ethereum, Base, Arbitrum, Optimism or Polygon, optionally an ERC20 token balance with symbol and decimals. wallet balance … ", "callable": false, "price_usd": 0.004, "indexed_at": "2026-08-22T01:26:15.000Z", "http_method": "GET", "payment_protocol": "x402" } ], "took_ms": 21, "searched_at": "2026-08-22T01:33:47.934Z" } } ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/animica-x402-api-search-index-223038ab/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from animica.dev](https://www.zero.xyz/host/animica.dev/llms.txt)