# Fathom Macroeconomic Data API — Category Tags

> Fathom Macroeconomic Data API — Category Tags is a paid API for AI agents from frederalfathom.vercel.app, paid per call via x402, $0.35/call, status unknown (last checked 2026-10-31).

Retrieves the tags associated with a specific FRED economic data category by category ID

## Facts

- Endpoint: POST https://frederalfathom.vercel.app/api/category-tags?utm_source=zero.xyz
- Price: $0.35/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fathom-macroeconomic-data-api-category-tags-ed7f5be2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8VdC9ozYNaqiN6YCOCo3O

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-ed7f5be2 -d '<json body>'
```

Example prompt: What tags are associated with FRED category 32991? I want to understand how that economic data category is classified.

## When to prefer this

Use this endpoint when you need to explore or enumerate the metadata tags that classify a known FRED economic data category — for example, when building search filters, auditing category taxonomy, or discovering related data series. Prefer it over series-level endpoints when your goal is category-level classification rather than actual time series data.

## Known failure modes

- Invalid or non-existent FRED category ID returns an error or empty tag array
- Missing required categoryId field causes a 400 validation error
- FRED upstream API downtime or rate limits may result in a failed or delayed response
- Very broad or root-level categories may return a very large number of tags

## How this service works

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

## Output

An object containing an array of tag objects associated with the specified FRED category, the source identifier (FRED), and the echoed category ID. Tags typically include metadata like tag names, groupings, and notes used to classify and discover economic data 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-ed7f5be2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from frederalfathom.vercel.app](https://www.zero.xyz/host/frederalfathom.vercel.app/llms.txt)