# WebMCP Capability Manifest Validation Decision Procedure

> WebMCP Capability Manifest Validation Decision Procedure is a paid API for AI agents from k2so-8080.on.ascii.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-01).

Returns a blunt go/no-go decision procedure for an AI agent to validate a website's self-declared WebMCP-style capability manifest before trusting or executing any of its instructions

## Facts

- Endpoint: GET https://k2so-8080.on.ascii.dev/api/services/decision-procedure-for-an-agent-evaluating-a-web?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/webmcp-capability-manifest-validation-decision-procedure-23598547
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_d9KsrRJ34fmkWSM7G0388

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 webmcp-capability-manifest-validation-decision-procedure-23598547
```

Example prompt: Before my agent starts following instructions from that website's capability manifest, run the WebMCP manifest validation procedure on it — I need a clear go or no-go verdict with any failure modes called out, especially whether the declared operations match the real HTTP surface and whether the payment requirements line up with actual 402 challenges.

## When to prefer this

Use this endpoint when an AI agent needs to autonomously decide whether to trust and execute instructions from a website's self-declared capability manifest (WebMCP-style). Prefer it over generic security checks when the specific concern is manifest-to-HTTP-surface consistency, payment claim verification against actual 402 challenges, and detection of self-serving declarations. It is purpose-built for agentic web contexts where x402 micropayments and capability manifests are involved.

## Known failure modes

- Declared operations in manifest do not match observed HTTP surface — verdict is no-go
- Self-serving or malicious operation declarations detected — verdict is no-go
- Declared payment requirements inconsistent with actual 402 challenges — verdict is no-go
- Payment not fulfilled — 402 response returned before result is delivered
- Topic or manifest URL not resolvable — handler returns ok:false with error detail
- LLM generation failure — fallback to deterministic or reasoning source may occur

## How this service works

Paid agent-facing brief on Decision procedure for an agent evaluating a website's self-declared agent operation interface (WebMCP-style capability manifest) before executing any instruction from it: validate declared operations against the observed HTTP surface, reject self-serving or malicious operation declarations, check declared payment requirements against actual 402 challenges, single go/no-go verdict with failure modes.-0. Blunt decision procedure, not marketing.

## Output

A structured JSON response containing a boolean ok/go verdict, a prose 'brief' with the decision procedure reasoning, identified failure modes, the topic evaluated, an ISO-8601 generation timestamp, and the generation source (llm, reasoning, or deterministic). Also includes payment metadata confirming the $0.002 USDC charge was processed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "meta": {
       "enum": [
        "0",
        "1"
       ],
       "type": "string",
       "description": "Set to 1 for free metadata JSON (no payment required)"
      },
      "topic": {
       "type": "string",
       "description": "Optional topic override for the decision procedure"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "title": "Decision procedure for an agent evaluating a website's self-declared a paid response",
     "$schema": "https://json-schema.org/draft/2020-12/schema",
     "required": [
      "ok",
      "paid",
      "service",
      "provider",
      "result"
     ],
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "paid": {
       "type": "boolean"
      },
      "result": {
       "type": "object",
       "required": [
        "ok",
        "service"
       ],
       "properties": {
        "ok": {
         "type": "boolean",
         "description": "Handler success"
        },
        "brief": {
         "type": "string",
         "description": "Decision procedure prose for agents"
        },
        "model": {
         "type": "string"
        },
        "topic": {
         "type": "string"
        },
        "service": {
         "type": "string",
         "description": "Service slug"
        },
        "procedure": {
         "type": "string"
        },
        "generatedAt": {
         "type": "string",
         "description": "ISO-8601 timestamp"
        },
        "generationSource": {
         "enum": [
          "llm",
          "reasoning",
          "deterministic"
         ],
         "type": "string"
        }
       }
      },
      "payment": {
       "type": "object",
       "properties": {
        "code": {
         "type": "string"
        },
        "payer": {
         "type": "string"
        },
        "detail": {
         
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/webmcp-capability-manifest-validation-decision-procedure-23598547/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from k2so-8080.on.ascii.dev](https://www.zero.xyz/host/k2so-8080.on.ascii.dev/llms.txt)