# x402 Listing Watch

> x402 Listing Watch is a paid API for AI agents from conclavex402p04.pythonanywhere.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-16).

Snapshot or change-detect a single listing from a fixed public x402 directory (payapi, cdp, payai, bazaar) by ID or payTo address, with optional since-last-seen change detection.

## Facts

- Endpoint: GET https://conclavex402p04.pythonanywhere.com/v1/listing-watch/:directory/:id?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-listing-watch-a7e9eb92
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jXDs9r_EUmHtfgS_fP28O

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 x402-listing-watch-a7e9eb92
```

Example prompt: Before I pay that x402 seller, can you snapshot their listing from the bazaar directory using seller ID abc123 and check if anything changed since timestamp 2024-06-01T00:00:00Z?

## When to prefer this

Use this endpoint when an AI agent needs to verify or snapshot a specific x402 seller listing before trusting or paying them, or when monitoring whether a previously seen listing has changed. Prefer this over the x402 Integrity Check endpoint when the goal is directory-level listing lookup and change detection rather than catalog-vs-live integrity verification of a full x402 service response.

## Known failure modes

- Listing ID or payTo address not found in specified directory — returns 404 or not-found error
- Invalid directory name (must be one of payapi, cdp, payai, bazaar) — returns validation error
- Malformed since= timestamp — returns parameter error
- Directory temporarily unavailable — returns upstream error
- Rate limiting or payment failure — returns 402 or 429

## How this service works

Call before trusting or paying a third-party x402 seller: snapshot one listing from a fixed public directory (payapi, cdp, payai, bazaar) by its id/payTo, or pass ?since= to get told whether it changed since you last saw it. Reads public directories only - never a caller-supplied URL - and returns already-public fields (JSON).

## Output

Returns a JSON snapshot of the requested listing's public fields (e.g. name, description, price, payTo address) from the specified directory. If a ?since= timestamp is provided, also returns a flag or indicator of whether the listing changed since that time. Reads only from fixed public directories; no caller-supplied URLs are followed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "pathParams": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-listing-watch-a7e9eb92/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from conclavex402p04.pythonanywhere.com](https://www.zero.xyz/host/conclavex402p04.pythonanywhere.com/llms.txt)