# US Government Federal Register Search (x402)

> US Government Federal Register Search (x402) is a paid API for AI agents from test5-x402-gov.stackstats.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-20).

Pay-per-call keyword search of US Federal Register documents via an unofficial proxy backed by federalregister.gov

## Facts

- Endpoint: GET https://test5-x402-gov.stackstats.workers.dev/fedreg/search?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/us-government-federal-register-search-x402-d7252598
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MsYsRcNs886fW3eVMXFpn

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 us-government-federal-register-search-x402-d7252598
```

Example prompt: Search the Federal Register for documents about 'cybersecurity surface transportation' and show me the first 10 results from page 1.

## When to prefer this

Use this endpoint when you need keyword-based search across Federal Register documents (notices, proposed rules, final rules, executive orders) and want a simple pay-per-call interface without setting up your own federalregister.gov API integration. Prefer it for ad-hoc regulatory research, compliance monitoring, or legal discovery tasks where direct government API access isn't already configured. Not suitable when you need real-time guaranteed accuracy, bulk downloads, or structured access to other US government datasets beyond the Federal Register.

## Known failure modes

- Missing required 'q' query parameter returns a validation error
- Query exceeding 200 characters may be rejected or truncated
- Page number outside 1-5 range returns an error
- limit outside 1-25 range returns a validation error
- Upstream federalregister.gov API unavailability causes failures
- Payment of $0.005 USDC not provided results in HTTP 402 response
- Results are unofficial and may lag or differ from the authoritative source

## How this service works

Pay-per-call search of public US government data. Unofficial; verify at source. Provided AS IS with no warranty of any kind, express or implied, including accuracy, completeness, timeliness, merchantability or fitness for a particular purpose. Not affiliated with or endorsed by any U.S. government agency.

## Output

Returns a JSON object containing a paginated list of Federal Register documents matching the search query, including each document's title, type (e.g. Notice, Rule, Proposed Rule), document number, publication date, HTML and PDF URLs, and associated agencies. Also includes total result count, total pages, cache status (hit/miss), the source URL used to fetch data, a disclaimer label, and a link to federalregister.gov API terms.

## 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": [
      "q"
     ],
     "properties": {
      "q": {
       "type": "string",
       "description": "Search keywords (max 200 chars)"
      },
      "page": {
       "type": "integer",
       "default": 1,
       "maximum": 5,
       "minimum": 1,
       "description": "Page number 1-5"
      },
      "limit": {
       "type": "integer",
       "default": 10,
       "maximum": 25,
       "minimum": 1,
       "description": "Rows per page (max 25)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "label",
      "disclaimer",
      "source_url",
      "data"
     ],
     "properties": {
      "data": {
       "type": "object",
       "required": [],
       "properties": {
        "count": {
         "type": "integer"
        },
        "results": {
         "type": "array",
         "items": {
          "type": "object",
          "required": [],
          "properties": {
           "type": {
            "type": "string"
           },
           "title": {
            "type": "string"
           },
           "pdf_url": {
            "type": "string"
           },
           "abstract": {
            "type": [
             "string",
             "null"
            ]
           },
           "agencies": {
            "type": "array"
           },
           "html_url": {
            "type": "string"
           },
           "document_number": {
            "type": "string"
           },
           "publication_date": {
            "type": "string"
           }
          }
         }
        },
        "total_pages": {
         "type": "integer"
        }
       }
      },
      "cache": {
       "enum": [
        "hit",
        "miss"
       ],
       "type": "string"
      },
      "label": {
       "type": "string",
       "const": "Unofficial; verify at source"
      },
      "disclaimer": {
       "type": "string"
      
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {
   "count": 4669,
   "results": [
    {
     "type": "Notice",
     "title": "Cybersecurity Measures for Surface Modes",
     "html_url": "https://www.federalregister.gov/d/2026-12345",
     "document_number": "2026-12345",
     "publication_date": "2026-10-01"
    }
   ],
   "total_pages": 5
  },
  "cache": "miss",
  "label": "Unofficial; verify at source",
  "disclaimer": "Unofficial; verify at source. Provided AS IS with no warranty of any kind, express or implied, including accuracy, completeness, timeliness, merchantability or fitness for a particular purpose. Not affiliated with or endorsed by any U.S. government agency.",
  "source_url": "https://www.federalregister.gov/api/v1/documents.json?per_page=1&page=1&conditions[term]=cybersecurity",
  "source_terms": "https://www.federalregister.gov/reader-aids/developer-resources/rest-api"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/us-government-federal-register-search-x402-d7252598/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from test5-x402-gov.stackstats.workers.dev](https://www.zero.xyz/host/test5-x402-gov.stackstats.workers.dev/llms.txt)