# SperaxOS ERC-8004 Agent Registration

> SperaxOS ERC-8004 Agent Registration is a paid API for AI agents from chat.sperax.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-19).

Registers a new ERC-8004 agent identity on-chain with a name, description, metadata URI, and wallet address via the SperaxOS x402 API

## Facts

- Endpoint: POST https://chat.sperax.io/api/x402/v1/erc8004/register?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/speraxos-erc-8004-agent-registration-b06d0d26
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CLmQdn8WTJLynGQW0dY4w

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-registration-b06d0d26 -d '<json body>'
```

Example prompt: Register my AI agent called 'YieldBot' on Arbitrum with the description 'Autonomous DeFi yield optimizer' and link it to my wallet 0xAbC1234567890abcdef1234567890abcdef123456 using the metadata URI https://mymeta.io/yieldbot.json — pay the $0.001 USDC fee via x402.

## When to prefer this

Use this endpoint when you need to create a verifiable, on-chain ERC-8004 identity record for an AI agent, linking a wallet address to a human-readable name and metadata. Prefer this over off-chain identity systems when blockchain-level verifiability and discoverability are required. It is ideal for autonomous agent fleets that need persistent, decentralized identities payable without API keys via USDC micropayments.

## Known failure modes

- Invalid wallet address format (not a 0x-prefixed 40-hex-char address) returns a validation error
- Metadata URI is not a valid URI format — returns schema validation error
- Name exceeds 256 characters or is empty — returns length validation error
- Description exceeds 2000 characters — returns length validation error
- Insufficient USDC balance to cover $0.001 x402 micropayment — payment fails before request is processed
- x402 payment header malformed or missing — returns 402 Payment Required
- Chain identifier not supported — returns error or defaults to Arbitrum
- Duplicate registration for the same wallet/name combination may return a conflict error

## 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

Returns a confirmation of the on-chain ERC-8004 agent registration, including the registered agent's name, wallet address, chain, description, and metadata URI, along with a transaction or record identifier confirming the registration was created on the target chain.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "name": {
   "type": "string",
   "maxLength": 256,
   "minLength": 1
  },
  "chain": {
   "type": "string",
   "default": "arbitrum"
  },
  "description": {
   "type": "string",
   "maxLength": 2000
  },
  "metadataUri": {
   "type": "string",
   "format": "uri"
  },
  "walletAddress": {
   "type": "string",
   "pattern": "^0x[a-fA-F0-9]{40}$"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/speraxos-erc-8004-agent-registration-b06d0d26/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)