# Paddock Circular Signal — AI Agent Commerce Self-Funding Detection

> Paddock Circular Signal — AI Agent Commerce Self-Funding Detection is a paid API for AI agents from paddock.finance, paid per call via x402, $0.99/call, status unknown (last checked 2026-09-15).

Returns facilitator-level data detecting circular/self-funding payment patterns in AI agent commerce, including cluster volume, self-funding percentage, and flagged share of listed endpoints.

## Facts

- Endpoint: GET https://paddock.finance/api/paddock/mcp/circular-signal
- Price: $0.99/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/paddock-circular-signal-ai-agent-commerce-self-funding-detection-370d7c03
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_s9Ar08WESdKSNdF5B2Li7

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 paddock-circular-signal-ai-agent-commerce-self-funding-detection-370d7c03
```

Example prompt: Pull the Paddock circular signal for the last 30 days — I want to see which facilitators have high self-funding percentages and how much of their listed volume is flagged.

## When to prefer this

Use this endpoint when you need to assess payment integrity, detect self-dealing or circular transaction patterns, or audit facilitators in the AI agent commerce ecosystem. Prefer this over generic analytics endpoints when the specific question is about whether payment volume is organic vs. self-funded, or when flagging suspicious cluster behavior across facilitators.

## Known failure modes

- Invalid window parameter (must be '7d' or '30d') returns a validation error
- Payment not included or insufficient (x402 protocol) returns 402 Payment Required
- Endpoint unavailable or data not yet computed returns 503 or empty response
- Malformed input object missing required 'type' or 'method' fields returns schema validation error

## How this service works

The live, neutral, citable source for what AI agents are paying for and where the market is concentrating. Free dashboards, API & MCP, monthly intelligence report.

## Output

A JSON object containing a list of facilitators, each with: trend (e.g. stable), facilitator name, cluster count, self-funding percentage, cluster volume in USD for 7d and 30d windows, external payer count, and flagged share of listed percentage. Also includes the methodology version used.

## 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"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "window": {
       "enum": [
        "7d",
        "30d"
       ],
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "tool": "get_circular_signal",
  "facilitators": [
   {
    "trend": "stable",
    "facilitator": "meridian",
    "cluster_count": 2,
    "self_funding_pct": 100,
    "cluster_volume_usd": {
     "d7": 41203.84,
     "d30": 215915.91
    },
    "external_payer_count": 0,
    "flagged_share_of_listed_pct": 1.06
   }
  ],
  "methodology_version": "v0.1"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/paddock-circular-signal-ai-agent-commerce-self-funding-detection-370d7c03/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from paddock.finance](https://www.zero.xyz/host/paddock.finance/llms.txt)