# SperaxOS ERC-8004 Agent Search

> SperaxOS ERC-8004 Agent Search is a paid API for AI agents from chat.sperax.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-18).

Searches for on-chain AI agents registered under the ERC-8004 standard by name, description, or service type on a specified blockchain

## Facts

- Endpoint: POST https://chat.sperax.io/api/x402/tools/erc8004/searchAgents?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/speraxos-erc-8004-agent-search-e5ca79c1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WiUPU_YpSEX1LqS7pBCCG

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 speraxos-erc-8004-agent-search-e5ca79c1 -d '<json body>'
```

Example prompt: Search the ERC-8004 agent registry on BSC testnet for any A2A agents related to DeFi trading — show me up to 10 results.

## When to prefer this

Use this endpoint when you need to discover AI agents registered on-chain via the ERC-8004 standard, especially when filtering by service type (A2A, MCP, inference) or searching by name/description keyword. Prefer this over off-chain agent directories when you need trustless, on-chain provenance of agent registrations on supported EVM networks.

## Known failure modes

- No agents found matching the query — returns empty result set
- Invalid chain identifier — chain not recognized or unsupported
- Network timeout or RPC error connecting to the specified blockchain
- Invalid serviceType filter value — unrecognized service type enum
- Limit parameter out of range — request rejected or clamped

## How this service works

AI-powered DeFi intelligence APIs payable via the x402 HTTP payment protocol. No API key required — pay per request with USDC on Base. Identity-only (SIWX) endpoints are free for wallets with an agentcash identity.

## Output

A list of on-chain AI agents matching the search criteria, including agent names, descriptions, service types, and blockchain registry metadata — up to the specified result limit.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "type": "string",
   "default": "bsc-testnet",
   "description": "Blockchain to search on"
  },
  "limit": {
   "type": "number",
   "default": 10,
   "description": "Maximum results to return"
  },
  "query": {
   "type": "string",
   "description": "Search term to match against agent names and descriptions"
  },
  "serviceType": {
   "type": "string",
   "description": "Filter by service type (e.g., A2A, MCP, inference)"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/speraxos-erc-8004-agent-search-e5ca79c1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chat.sperax.io](https://www.zero.xyz/host/chat.sperax.io/llms.txt)