# Dev Reference – HTTP Status Code Lookup

> Dev Reference – HTTP Status Code Lookup is a paid API for AI agents from dev-reference.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-31).

Returns the meaning, typical cause, client action, and cacheability of any HTTP status code from the IANA registry and RFC 9110.

## Facts

- Endpoint: GET https://dev-reference.x402tookit.com/http-status?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/dev-reference-http-status-code-lookup-dbbc2c90
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_JRNA8AOuqCkgxq533bgqz

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 dev-reference-http-status-code-lookup-dbbc2c90
```

Example prompt: What does HTTP status code 429 mean — what causes it, should my client retry, and is it cacheable by default?

## When to prefer this

Choose this endpoint when you need authoritative, spec-grounded information about a specific HTTP status code — including its IANA registration status, RFC 9110 semantics, cacheability, and actionable client guidance. Prefer it over general web search when you need structured, machine-readable output for use in retry logic, error handling, documentation generation, or developer tooling.

## Known failure modes

- Code out of range (below 100 or above 599) — likely returns an error or null fields
- Unregistered or proprietary status codes may return partial data with registered=false
- Missing required 'code' query parameter returns a validation error
- Non-integer input rejected by schema validation

## How this service works

HTTP status code meaning, typical cause, client action and cacheability, from the IANA registry and RFC 9110.

## Output

A structured record containing the status code number, its official name, class (1xx–5xx), one-line meaning, typical cause, recommended client action, retry hint, whether it is cacheable by default, whether it is IANA-registered, the authoritative RFC reference, any vendor-specific notes, and a summary verdict — all sourced from the IANA registry and RFC 9110.

## 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",
     "required": [
      "code"
     ],
     "properties": {
      "code": {
       "type": "integer",
       "description": "Status code, 100 to 599"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "code": {
       "type": [
        "null",
        "number"
       ]
      },
      "name": {
       "type": [
        "null",
        "string"
       ]
      },
      "class": {
       "type": [
        "null",
        "string"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "vendor": {},
      "meaning": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "reference": {
       "type": [
        "null",
        "string"
       ]
      },
      "retryHint": {
       "type": [
        "null",
        "string"
       ]
      },
      "classDigit": {
       "type": [
        "null",
        "number"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "registered": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "clientAction": {
       "type": [
        "null",
        "string"
       ]
      },
      "registryNote": {},
      "typicalCause": {
       "ty
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/dev-reference-http-status-code-lookup-dbbc2c90/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from dev-reference.x402tookit.com](https://www.zero.xyz/host/dev-reference.x402tookit.com/llms.txt)