# Fathom Macroeconomic Data API — Series Search

> Fathom Macroeconomic Data API — Series Search is a paid API for AI agents from fsthum.vercel.app, paid per call via x402, $0.4/call, status unknown (last checked 2026-10-30).

Searches 816,000+ FRED-powered economic time series by keyword, returning matching macroeconomic data series metadata

## Facts

- Endpoint: POST https://fsthum.vercel.app/api/search?utm_source=zero.xyz
- Price: $0.4/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fathom-macroeconomic-data-api-series-search-3fcca754
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YuxpYQKTJtRmHcwmS6nBp

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-search-3fcca754 -d '<json body>'
```

Example prompt: Search the FRED macroeconomic database for time series related to 'US inflation rate' and return the top 5 matching economic indicators.

## When to prefer this

Use this endpoint when you need to discover or search across FRED's massive catalog of 816,000+ macroeconomic time series by keyword. Prefer this over direct FRED API access when you need a pre-built, payment-ready search interface. Best for agents that need to dynamically find relevant economic indicators without knowing the exact FRED series ID in advance.

## Known failure modes

- Missing required 'query' field returns a 400 or error response
- Empty query string may return zero results or an error
- Overly broad queries may return irrelevant series
- FRED upstream unavailability may cause failures
- Limit parameter passed as non-string may cause validation errors

## 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 a JSON object containing the search query echo, data source attribution, total count of matching series, and an array of matching economic time series objects (each with series metadata such as ID, title, frequency, units, and observation dates) from the FRED database.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "query"
 ],
 "properties": {
  "limit": {
   "type": "string",
   "description": "Max results (default: 10)"
  },
  "query": {
   "type": "string",
   "description": "Search keywords (e.g. 'inflation rate', 'housing starts')"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "source"
 ],
 "properties": {
  "count": {
   "type": "number"
  },
  "query": {
   "type": "string"
  },
  "series": {
   "type": "array",
   "items": {
    "type": "object"
   }
  },
  "source": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fathom-macroeconomic-data-api-series-search-3fcca754/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fsthum.vercel.app](https://www.zero.xyz/host/fsthum.vercel.app/llms.txt)