# Agent Readiness llms.txt Substantive Repair Check

> Agent Readiness llms.txt Substantive Repair Check is a paid API for AI agents from agentreadiness.halowerk.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-14).

Fetches public evidence from a target URL and evaluates whether its llms.txt file is substantive enough to guide AI agents, returning a verdict, evidence, and a concrete repair action.

## Facts

- Endpoint: POST https://agentreadiness.halowerk.com/v1/llms-substantive-repair?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-readiness-llms-txt-substantive-repair-check-09e386e2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uYTcChA0yPJolZvb6WlR0

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 agent-readiness-llms-txt-substantive-repair-check-09e386e2 -d '<json body>'
```

Example prompt: Check whether the llms.txt at example.com is substantive enough to properly guide AI agents — give me the verdict, what evidence you found, and a specific repair plan if it falls short.

## When to prefer this

Choose this endpoint when you specifically need to evaluate whether a site's llms.txt is substantive and actionable (not just present), and want a concrete repair recommendation. Prefer this over the 'llms.txt available' check when you already know the file exists but need to assess its quality and content depth. Ideal for site owners, SEO/AI-readiness auditors, or agents building optimization pipelines.

## Known failure modes

- Target URL is unreachable or returns non-200 status — check fails with a network error
- llms.txt file is missing entirely — returns a specific not-found observation rather than a substantive check
- Target is behind authentication or a firewall — passive check cannot access the file
- Malformed target URL — validation error returned before any fetch is attempted
- Rate limiting or bot blocking on the target domain prevents fetching

## How this service works

Substantive llms.txt repair plan fetches current public evidence from the supplied target and evaluates the documented criterion. It returns the observation, threshold, verdict, exact evidence source, limitations and a mode-specific action. The check is passive: no login attempt, payload injection, exploit, purchase, form submission or load test is performed.

## Output

Returns a structured report including: the observation (what was found in the llms.txt), the threshold criteria being evaluated, a pass/fail verdict, the exact evidence source URL, known limitations of the passive check, and a mode-specific repair action the site owner can take to bring the llms.txt up to standard.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "target": {
   "type": "string",
   "maxLength": 2048,
   "minLength": 3,
   "description": "Public HTTP(S) URL or domain to inspect. A bare domain is normalized to HTTPS."
  },
  "context": {
   "type": "object",
   "description": "Optional non-secret correlation labels returned unchanged only in the request lifecycle.",
   "maxProperties": 12,
   "additionalProperties": {
    "type": [
     "string",
     "number",
     "boolean",
     "null"
    ]
   }
  },
  "baseline": {
   "type": [
    "object",
    "null"
   ],
   "description": "Optional baseline returned by a previous snapshot call.",
   "additionalProperties": true
  },
  "compare_url": {
   "type": "string",
   "maxLength": 2048,
   "minLength": 3,
   "description": "Optional public comparison URL. Used by change and monitoring services."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-readiness-llms-txt-substantive-repair-check-09e386e2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentreadiness.halowerk.com](https://www.zero.xyz/host/agentreadiness.halowerk.com/llms.txt)