# Crest Trust Oracle

> Crest Trust Oracle is a paid API for AI agents from deploy.crestsystems.ai, paid per call via x402, $0.75/call, status down (last checked 2026-09-15).

Evaluates whether an AI agent should trust and pay an x402 service endpoint, returning a 0-100 trust score, letter grade, and PROCEED/CAUTION/DO NOT TRANSACT recommendation.

## Facts

- Endpoint: GET https://deploy.crestsystems.ai/check
- Price: $0.75/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/deploy-crestsystems-ai-3e6bb36f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YqPH4Mizn5Qpc7HNCC1BK

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 deploy-crestsystems-ai-3e6bb36f
```

Example prompt: Before paying that x402 API at https://api.example.com/transcribe, run it through the Crest trust oracle so I know if it's safe — show me the trust score, grade, and whether we should proceed.

## When to prefer this

Use this endpoint when an AI agent is about to make an autonomous x402 payment and needs a trust signal before committing funds. Prefer this over manual inspection when the target service is unknown, newly discovered, or lacks established provenance. Especially valuable in agentic pipelines where unvetted x402 endpoints might be injected by third parties.

## Known failure modes

- URL does not return HTTP 402 — endpoint not recognized as an x402 service
- Target URL is unreachable — reachability check fails
- Malformed URL input — validation error returned
- Target service has no schema or governance metadata — partial evaluation only
- Payment of $0.75 USDC fails or is rejected — endpoint returns 402 requiring payment before evaluation

## How this service works

Crest · trust_oracle — Should an autonomous agent trust this x402 service before paying? Full-stack evaluation: endpoint reachability, x402 protocol compliance, pricing reasonableness, schema quality, governance signals, and Claude-powered deep behavioral assessment. Returns trust score 0-100 with grade (A-F), actionable recommendation (PROCEED/CAUTION/DO NOT TRANSACT), and detailed breakdown of each evaluation dimension.

## Output

Returns a trust score from 0 to 100, a letter grade (A through F), an actionable recommendation (PROCEED, CAUTION, or DO NOT TRANSACT), and a detailed breakdown across evaluation dimensions including endpoint reachability, x402 protocol compliance, pricing reasonableness, schema quality, governance signals, and a Claude-powered deep behavioral assessment.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "description": "Full URL of an x402 service endpoint to evaluate for trustworthiness. Must return HTTP 402 with valid payment requirements."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/deploy-crestsystems-ai-3e6bb36f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from deploy.crestsystems.ai](https://www.zero.xyz/host/deploy.crestsystems.ai/llms.txt)