# AEML x402 Trust Precheck

> AEML x402 Trust Precheck is a paid API for AI agents from aeml-x402.zeabur.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Returns a pre-payment trust snapshot for an x402 service, including score_total, liveness_state, streak, lifecycle metadata, and record_hash from a July 2026 census snapshot.

## Facts

- Endpoint: GET https://aeml-x402.zeabur.app/trust/precheck
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/aeml-x402-trust-precheck-8c03528f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xg23FaPP0DH0HwnkQaKlw

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 aeml-x402-trust-precheck-8c03528f
```

Example prompt: Before I pay for that x402 service with ID 'svc-abc123', can you pull the trust precheck and tell me its score, liveness state, and how long it's been running?

## When to prefer this

Use this endpoint when you need a quick, low-cost ($0.01 USDC) pre-payment trust check on an x402 service before committing to a call. It is specifically designed for the x402 micropayment ecosystem and surfaces liveness, scoring, and lifecycle metadata. Accept that some fields will be unavailable due to degraded delivery mode — the endpoint is honest about this via unavailable_fields. Do not use if you need real-time verified scoring, tier data, or on-chain verification, as those fields are permanently unavailable from this source.

## Known failure modes

- Missing or invalid service ID returns error or empty result
- Data is from a 2026-07-08 census snapshot and may be stale (data_age_hours will be large)
- Many fields (tier, verified, action_hint, onchain_*) are consistently unavailable due to collector shutdown — returned as unavailable_fields
- score_total may be null if scoring data was not captured
- Network or upstream service unavailability on zeabur.app

## How this service works

[SIGNAL+PROOF] Demand record for one x402 service (?service=): demand_class (REAL/SOLO/PROBE/WASH), calls_30d, unique_payers_30d, score_total, liveness_state, lifecycle, record_hash. Model demand-v1, refreshed daily from the public CDP catalogue; score_total is an ordering key, not a rating. DEGRADED DELIVERY, see unavailable_fields - tier, verified, action_hint and the five-axis sub-scores are empty. Descriptive only, never a forecast or advice. No data -> 422 no_charge, not billed.

## Output

Returns a JSON object with service_id, score_total (overall trust score), liveness_state (e.g. active/inactive), liveness_streak (consecutive liveness count), lifecycle object, record_hash, observed_at timestamp, capture_date, data_age_hours, baseline_delta, and an unavailable_fields array listing fields that could not be populated due to the original collector being offline (tier, verified, action_hint, five-axis subscores, onchain_* fields). Also includes source_note and unavailable_reason explaining degraded delivery.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "GET"
     ]
    },
    "queryParams": {
     "type": "object",
     "additionalProperties": false,
     "properties": {
      "service": {
       "type": "string",
       "description": "required - x402 service id; samples at free /trust/preview (sample_ids)",
       "examples": [
        "api-exa-ai"
       ]
      }
     },
     "required": [
      "service"
     ]
    }
   },
   "required": [
    "type",
    "method",
    "queryParams"
   ]
  },
  "output": {
   "type": "object",
   "properties": {
    "type": {
     "const": "json"
    },
    "example": {}
   },
   "required": [
    "type"
   ]
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/aeml-x402-trust-precheck-8c03528f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from aeml-x402.zeabur.app](https://www.zero.xyz/host/aeml-x402.zeabur.app/llms.txt)