# US Federal Agencies Directory

> US Federal Agencies Directory is a paid API for AI agents from us-regulations.use.x402atlas.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-28).

Returns Federal Register agency slugs, names, short names, and parent-child relationships, searchable by substring.

## Facts

- Endpoint: GET https://us-regulations.use.x402atlas.com/agencies?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-28
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/us-federal-agencies-directory-8fed3d97
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__f9Nrn8grG7hn3dZ9VYRE

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-federal-agencies-directory-8fed3d97
```

Example prompt: Can you find the Federal Register slug for the Environmental Protection Agency so I can use it to filter EPA regulations?

## When to prefer this

Use this endpoint when you need to resolve a human-readable agency name or abbreviation into the exact Federal Register slug required by regulation search or filter endpoints. Prefer this over guessing slugs, as agency names may have unexpected formatting (e.g. hyphens, abbreviations). Essential as a prerequisite step before calling US Regulation Search, US Regulation Counts, or US Regulation Updates endpoints on the same platform.

## Known failure modes

- Empty results array if no agency matches the query substring
- Query too long (over 200 characters) rejected at input validation
- Network or payment authorization failure returns no data
- Ambiguous short substring may return too many results requiring refinement

## How this service works

US federal agency directory — the Federal Register's agency slugs, names, short names and parent-child links, searchable by substring. Use to find the slug an agency filter needs, e.g. environmental-protection-agency for the EPA.

## Output

Returns a JSON object with a list of matching agencies, each containing: slug (for use in regulation API filters), full name, short name (if any), parent agency slug (empty for top-level), and list of child agency slugs. Also includes retrieval timestamp, query echo, result count, source citation, and a normalization caveat.

## 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": [
      "query"
     ],
     "properties": {
      "query": {
       "type": "string",
       "maxLength": 200,
       "description": "Substring of slug, name or short name, case-insensitive"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "as_of",
      "source",
      "caveat",
      "modified",
      "query",
      "count",
      "agencies"
     ],
     "properties": {
      "note": {
       "type": "string",
       "description": "Present only on a sample or empty response"
      },
      "as_of": {
       "type": "string",
       "format": "date-time",
       "description": "Retrieval time, UTC"
      },
      "count": {
       "type": "integer"
      },
      "query": {
       "type": "string"
      },
      "caveat": {
       "type": "string",
       "description": "Fixed interpretation note"
      },
      "source": {
       "type": "object",
       "required": [
        "name",
        "url",
        "citation"
       ],
       "properties": {
        "url": {
         "type": "string"
        },
        "name": {
         "type": "string"
        },
        "citation": {
         "type": "string"
        }
       },
       "additionalProperties": false
      },
      "agencies": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "slug",
         "name",
         "short_name",
         "parent_slug",
         "children"
        ],
        "properties": {
         "name": {
          "type": "string"
         },
         "slug": {
          "type": "string",
          "description": "Pass to the agency filter"
         },
         "children": {
          "type": "array",
          "items": {
           "type": "string"
          },
          "description": "Sub-agency slugs"
         },
         "short_name": {
          "type": 
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/us-federal-agencies-directory-8fed3d97/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from us-regulations.use.x402atlas.com](https://www.zero.xyz/host/us-regulations.use.x402atlas.com/llms.txt)