# Fathom Macroeconomic Data API — Vintage Series

> Fathom Macroeconomic Data API — Vintage Series is a paid API for AI agents from fsthum.vercel.app, paid per call via x402, $0.4/call, status unknown (last checked 2026-10-29).

Retrieves vintage date data for a specific FRED economic time series, returning historical revision snapshots for macroeconomic indicators.

## Facts

- Endpoint: POST https://fsthum.vercel.app/api/vintage?utm_source=zero.xyz
- Price: $0.4/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fathom-macroeconomic-data-api-vintage-series-dfa64de8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_mBvns_R_SLLvQlOLF5H4t

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-vintage-series-dfa64de8 -d '<json body>'
```

Example prompt: Pull the vintage date history for the FRED series GDPC1 — I want to see the last 10 revision snapshots for US real GDP.

## When to prefer this

Choose this endpoint when you need historical revision snapshots (vintage dates) for a specific FRED macroeconomic series — particularly useful for understanding how economic data estimates have been revised over time. Prefer this over general data lookups when the focus is on data revisions rather than just current values, and when the FRED series ID is already known.

## Known failure modes

- Invalid or unknown FRED series ID returns an error or empty result
- Missing required seriesId field causes a validation error
- Limit parameter set too high may cause slow responses or truncated results
- Network or upstream FRED API unavailability causes request failure
- Malformed request body returns a 400-level 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 a JSON object containing the source name, the requested FRED series ID, and an array of vintage date objects representing historical data revision snapshots for that economic time series.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "seriesId"
 ],
 "properties": {
  "limit": {
   "type": "string",
   "description": "Max results (default: 10)"
  },
  "seriesId": {
   "type": "string",
   "description": "FRED series ID"
  }
 }
}
```

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fathom-macroeconomic-data-api-vintage-series-dfa64de8/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)