# HTTPay Agent Directory

> HTTPay Agent Directory is a paid API for AI agents from httpay.xyz, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Query and filter all ERC-8004 registered AI agents on the Base blockchain, paginated and searchable by capability.

## Facts

- Endpoint: POST https://httpay.xyz/api/agent-directory
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/httpay-xyz-278a13c9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_sUo05BtDtJjV-qLMrrvO2

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 httpay-xyz-278a13c9 -d '<json body>'
```

Example prompt: Can you search the on-chain ERC-8004 agent directory on Base and show me the first 10 agents that have a 'translation' capability?

## When to prefer this

Use this endpoint when you need to discover AI agents registered on the Base blockchain that conform to the ERC-8004 standard, especially when filtering by specific capabilities or paginating through large agent lists. Prefer this over generic Web2 agent directories when you need verified on-chain agent metadata.

## Known failure modes

- Payment required (402) if no x402 or MPP payment header is provided
- Invalid capability filter returns empty list
- Offset beyond total agent count returns empty results
- Malformed request body returns 400 error
- Base RPC unavailability may cause on-chain lookup failures

## How this service works

Query all ERC-8004 registered agents on Base. Filter by capability, paginate with limit/offset. Returns structured agent list with on-chain data and parsed metadata.

## Output

Returns a structured list of ERC-8004 registered agents on Base, including on-chain data and parsed metadata for each agent, filtered by the specified capability, with pagination support via limit and offset.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "description": "Query all ERC-8004 registered agents on Base. Filter by capability, paginate with limit/offset. Returns structured agent list with on-chain data and parsed metadata."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/httpay-xyz-278a13c9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from httpay.xyz](https://www.zero.xyz/host/httpay.xyz/llms.txt)