# Fathom Macroeconomic Data API — Series Tags

> Fathom Macroeconomic Data API — Series Tags is a paid API for AI agents from fredthom.vercel.app, paid per call via x402, $0.35/call, status unknown (last checked 2026-09-15).

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

## Facts

- Endpoint: POST https://fredthom.vercel.app/api/series-tags
- Price: $0.35/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fathom-macroeconomic-data-api-series-tags-73b0ce23
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_EFpS7Wn89kMmyDKsqvaVR

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-series-tags-73b0ce23 -d '<json body>'
```

Example prompt: What are the tags associated with the FRED series UNRATE — I want to know how it's classified and what topics it covers.

## When to prefer this

Use this endpoint when you need to discover the metadata classification tags for a specific FRED economic time series — useful for understanding what category, frequency, geography, or theme a series belongs to. Prefer this over a general series search when you already know the series ID and want enrichment metadata rather than the actual data values.

## Known failure modes

- Invalid or unknown FRED series ID returns empty tags array or error
- Series ID missing from request body returns validation error
- FRED upstream service unavailable causes proxy failure
- Malformed series ID string may return no results without explicit 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 series, along with the series ID and data source identifier. Tags typically include category labels, geographic scope, frequency, seasonal adjustment status, and topic classifications used to describe and group the economic time series.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fathom-macroeconomic-data-api-series-tags-73b0ce23/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fredthom.vercel.app](https://www.zero.xyz/host/fredthom.vercel.app/llms.txt)