# Header Semantics Decision – agentreadiness.halowerk.com

> Header Semantics Decision – agentreadiness.halowerk.com 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 live public evidence from a target URL and evaluates whether its HTTP response headers meet documented semantic criteria, returning a verdict, observations, thresholds, evidence source, limitations, and a recommended action.

## Facts

- Endpoint: POST https://agentreadiness.halowerk.com/v1/header-semantics-decision?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/header-semantics-decision-agentreadiness-halowerk-com-fdd3ce14
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XTjUjYv3YzkapVLEpDGdT

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 header-semantics-decision-agentreadiness-halowerk-com-fdd3ce14 -d '<json body>'
```

Example prompt: Can you check whether https://example.com has semantically correct HTTP response headers for AI agent readiness and give me a verdict with the evidence and any recommended actions?

## When to prefer this

Choose this endpoint when you need a passive, read-only, evidence-backed verdict on whether a specific public URL's HTTP response headers satisfy documented semantic criteria for AI agent readiness — especially when you want a structured observation, threshold, and actionable recommendation rather than a raw header dump. Prefer it over generic HTTP inspection tools when you need a compliance-oriented verdict with an audit trail and explicit evidence citation.

## Known failure modes

- Target URL is unreachable or returns a non-2xx status, resulting in inability to fetch evidence
- Target domain resolves but blocks automated HTTP requests, limiting observable headers
- Malformed or non-HTTP(S) URL input triggers a validation error
- Headers are present but ambiguous, leading to an inconclusive verdict with noted limitations
- Rate limiting or network timeouts may cause intermittent failures

## How this service works

Header semantics decision 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 response containing: a pass/fail/unknown verdict on the header semantics criterion, the raw observation drawn from live evidence, the threshold against which it was measured, the exact evidence source URL or header field, known limitations of the passive check, and a mode-specific action recommendation for remediation or next steps. The check is entirely passive — no login, injection, purchase, or form submission is performed.

## 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/header-semantics-decision-agentreadiness-halowerk-com-fdd3ce14/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)