# DDG Change Detection Service

> DDG Change Detection Service is a paid API for AI agents from agents.daedalusdevelopmentgroup.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Detects changes between two HTTP request/response states and returns a bounded result indicating whether a change occurred

## Facts

- Endpoint: POST https://agents.daedalusdevelopmentgroup.com/v1/change-detect
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ddg-change-detection-service-fb771d50
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wQ56K1NhjctnWcXrmBnqm

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 ddg-change-detection-service-fb771d50 -d '<json body>'
```

Example prompt: Check if the response from that JSON API endpoint has changed — POST to it with this body and tell me if anything is different from before.

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call change detection signal for HTTP-accessible resources without managing your own polling infrastructure. Best suited for agents that need to autonomously detect state changes on APIs or web endpoints and can pay $0.01 USDC per check via x402 multi-chain payment rails.

## Known failure modes

- Missing required 'input' or 'output' fields returns a validation error
- Invalid HTTP method (e.g. GET instead of POST/PUT/PATCH) rejected by schema
- Payment failure or insufficient USDC balance blocks the request via x402 protocol
- Malformed body or unsupported bodyType enum value causes rejection
- Target endpoint unreachable results in error response

## How this service works

Machine-payable DDG services for AI agents. Current public live payment rails are x402 multi-chain USDC and direct-crypto auto/manual for public receiving-address families. MPP/Stripe/Tempo is installed but pending live provider env plus penny-settlement proof before any MPP-live advertisement. DDG sells bounded artifacts/results, not raw provider account access.

## Output

A JSON object with an 'ok' boolean field indicating whether the change detection operation completed successfully, plus any detected change metadata.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input",
  "output"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object"
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": true
  },
  "output": {
   "type": "object",
   "required": [
    "type",
    "example"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "ok": true
    }
   },
   "additionalProperties": true
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ddg-change-detection-service-fb771d50/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agents.daedalusdevelopmentgroup.com](https://www.zero.xyz/host/agents.daedalusdevelopmentgroup.com/llms.txt)