# Fathom Macroeconomic Data API — Category Tags

> Fathom Macroeconomic Data API — Category Tags is a paid API for AI agents from fathoms.vercel.app, paid per call via x402, $0.04/call, status unknown (last checked 2026-09-14).

Returns the tags associated with a FRED economic data category, enabling discovery and filtering of time series within that category

## Facts

- Endpoint: POST https://fathoms.vercel.app/api/category-tags
- Price: $0.04/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fathom-macroeconomic-data-api-category-tags-b6c5fd12
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_iPA169dAC2L5v8b1hMlEa

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 fathom-macroeconomic-data-api-category-tags-b6c5fd12 -d '<json body>'
```

Example prompt: What tags are associated with FRED category 32992 (the Money, Banking, and Finance category)? I want to understand what topics are covered so I can narrow down which economic time series to pull.

## When to prefer this

Use this endpoint when you need to discover, enumerate, or filter the classification tags for a specific FRED economic category before pulling actual time series data. It is ideal for building metadata-driven navigation of the FRED data catalog, constructing filtered search queries, or understanding what subcategories and topic dimensions exist within a given category. Prefer this over general FRED search when you already have a category ID and need to understand its taxonomy.

## Known failure modes

- Invalid or non-existent categoryId returns an empty tags array or error
- FRED API upstream outage causes failure or delayed response
- Malformed request body missing required categoryId field returns a 400 error
- Rate limiting or payment verification failure returns a 402 or 429 error

## How this service works

Free macroeconomic data API powered by FRED. 816,000+ economic time series. GDP, inflation, unemployment, interest rates, and more.

## Output

Returns an array of tag objects associated with the specified FRED category, along with the data source identifier and the category ID that was queried. Each tag object describes a topic, frequency, geography, or other classification attribute that applies to time series within that category.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "categoryId"
 ],
 "properties": {
  "categoryId": {
   "type": "string",
   "description": "FRED category ID"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "source"
 ],
 "properties": {
  "tags": {
   "type": "array",
   "items": {
    "type": "object"
   }
  },
  "source": {
   "type": "string"
  },
  "category_id": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fathom-macroeconomic-data-api-category-tags-b6c5fd12/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fathoms.vercel.app](https://www.zero.xyz/host/fathoms.vercel.app/llms.txt)