# AgentProof Contract Score

> AgentProof Contract Score is a paid API for AI agents from agentproof-murex.vercel.app, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Measures API response stability and contract reliability before an agent automates against an endpoint

## Facts

- Endpoint: POST https://agentproof-murex.vercel.app/api/contract-score
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentproof-murex-vercel-app-caf9988c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2a_HX2ngXYES5ypae1k9a

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 agentproof-murex-vercel-app-caf9988c -d '<json body>'
```

Example prompt: Before I automate against the Stripe /v1/charges endpoint, can you score its contract stability using AgentProof — I want to know if the response structure is consistent enough to safely build a workflow on top of it?

## When to prefer this

Use this endpoint when you need to assess whether an external API is stable and predictable enough to automate against — especially before building agent workflows, setting up recurring automations, or integrating an unfamiliar third-party API. Prefer this over manual testing when you want a quantified stability score rather than anecdotal observations.

## Known failure modes

- Invalid or unreachable API endpoint URL provided — returns error indicating inability to fetch sample responses
- Insufficient response samples to compute a meaningful stability score — returns low-confidence score
- Payment failure for x402 micropayment — request rejected before processing
- Malformed request body missing required endpoint or sample data — returns 400 validation error

## How this service works

API contract score for agents - measure response stability before automation.

## Output

Returns a numeric contract stability score indicating how consistent and reliable the API's response structure is across calls, along with metrics about response variability and an assessment of automation readiness.

## Example request

```json
{
 "responses": [
  {
   "body": {},
   "status": 200
  }
 ]
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "schema": {
   "type": "object",
   "description": "Optional JSON Schema to score the responses against."
  },
  "responses": {
   "type": "array",
   "items": {
    "description": "Any JSON value."
   },
   "description": "Sample API responses to score for contract stability."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentproof-murex-vercel-app-caf9988c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentproof-murex.vercel.app](https://www.zero.xyz/host/agentproof-murex.vercel.app/llms.txt)