# 8k4 Protocol — Cross-Chain Identity Registration Lookup

> 8k4 Protocol — Cross-Chain Identity Registration Lookup is a paid API for AI agents from api.8k4protocol.com, paid per call via x402, $0.001/call, status down (last checked 2026-09-15).

Returns all cross-chain wallet registrations associated with a given canonical ERC-8004 global agent ID

## Facts

- Endpoint: GET https://api.8k4protocol.com/identity/%7Bglobal_id%7D
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/8k4-protocol-cross-chain-identity-registration-lookup-38e4d0d9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Du123IBDbqV5vCKuwMLgO

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 8k4-protocol-cross-chain-identity-registration-lookup-38e4d0d9
```

Example prompt: Can you look up all the cross-chain registrations for the agent with global ID eip155:8453:0x8004...:21480 on the 8k4 Protocol trust system, so I can see which chains and wallets it's registered under?

## When to prefer this

Use this endpoint when you need to enumerate all blockchain/chain registrations for a known ERC-8004 canonical global ID. Prefer this over the wallet-based resolve endpoint when you already have the canonical global_id and want the full set of cross-chain records rather than resolving by wallet address.

## Known failure modes

- global_id not found — returns empty array or 404
- malformed global_id format — returns 400 bad request
- payment not attached or insufficient — returns 402 payment required
- rate limit exceeded — returns 429 too many requests
- agent has no cross-chain registrations — returns empty array

## How this service works

Get cross-chain registrations for a canonical global ID

## Output

A JSON array of registration objects, each containing the chain name, wallet address, numeric agent_id, full global_id string, and ISO 8601 creation timestamp — one entry per registered chain for the given canonical agent identity.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": [
  {
   "chain": "base",
   "wallet": "0x...",
   "agent_id": 21480,
   "global_id": "eip155:8453:0x8004...:21480",
   "created_at": "2026-01-01T00:00:00+00:00"
  }
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/8k4-protocol-cross-chain-identity-registration-lookup-38e4d0d9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.8k4protocol.com](https://www.zero.xyz/host/api.8k4protocol.com/llms.txt)