# ylk-brief

> ylk-brief is a paid API for AI agents from ylk.one, paid per call via x402, $0.08/call, status down (last checked 2026-10-25).

Returns a composite due-diligence brief for a single x402 payTo address, bundling trust vetting, business profile, market pulse, and spike data in one paid call.

## Facts

- Endpoint: GET https://ylk.one/v1/x402/brief?utm_source=zero.xyz
- Price: $0.08/call
- Payment: x402
- Status: down
- Last checked: 2026-10-25
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ylk-brief-082cd579
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_LO8gMFafEKWQOD0E-5sRu

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 ylk-brief-082cd579
```

Example prompt: Run a full due-diligence brief on the x402 payTo address 0xAbC123...def on Base — I want the trust verdict, business profile, pulse, and any market spikes all in one report.

## When to prefer this

Choose this endpoint when you need a comprehensive, single-call due-diligence package on an x402 payTo address and want to avoid making separate calls to /v1/vet, pulse, and business endpoints. It is the paid upgrade path from /v1/vet and is ideal when you need trust verdict, business context, and live market signals together. Prefer sibling endpoints (ylk-vet, ylk-spikes, ylk-rails) when you only need one dimension of data and want to minimize cost.

## Known failure modes

- Missing or invalid payTo address (parameter 'a' not provided or not a valid 0x address) — returns 400 or error response
- Address not found in x402 settlement data — may return empty or sparse brief
- Payment failure (x402 $0.08 USDC not settled) — returns 402 Payment Required
- Address on wrong chain (not Base) — results may be incomplete or inapplicable
- Rate limiting or upstream data lag — returns 429 or stale data warning

## How this service works

Composite due-diligence brief: vet + business + pulse + market spikes header for one payTo. Paid upgrade after /v1/vet — replaces separate pulse/business Bazaar rows.

## Output

A composite JSON brief containing: trust verdict (organic/concentrated/fragile/solo/opaque), settlement data, business profile details, live market pulse metrics ($/hr, tx/hr vs 24h baseline), and recent market spike signals — all for the specified payTo address on Base.

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "a": {
       "type": "string",
       "description": "0x… x402 payTo / service wallet on Base (required at call time)"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ylk-brief-082cd579/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ylk.one](https://www.zero.xyz/host/ylk.one/llms.txt)