# Fathom Macroeconomic Data API — Vintage Dates

> Fathom Macroeconomic Data API — Vintage Dates is a paid API for AI agents from fredthom.vercel.app, paid per call via x402, $0.4/call, status unknown (last checked 2026-09-15).

Retrieves vintage dates for a FRED economic time series, showing when historical data revisions were published

## Facts

- Endpoint: POST https://fredthom.vercel.app/api/vintage
- Price: $0.4/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-vintage-dates-617082b2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bJn3qn7uVWMvJFc8L0EYG

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-dates-617082b2 -d '<json body>'
```

Example prompt: Using the Fathom FRED-powered API, fetch the vintage dates for the GDP series (series ID: GDP) and return up to 20 results so I can see when historical revisions were published.

## When to prefer this

Use this endpoint when you need to know the specific dates on which a FRED economic time series was revised or updated — i.e., vintage dates — rather than the actual data values themselves. Ideal for researchers doing real-time data analysis, backtesting economic models with point-in-time data, or auditing when macroeconomic indicators were revised.

## Known failure modes

- Invalid or unknown FRED series ID returns an error or empty vintage_dates array
- Missing required seriesId parameter causes a 400-level validation error
- Network or Vercel hosting timeout on large series with many vintages
- Limit parameter ignored or misformatted may return default 10 results silently

## 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 object containing the source identifier, the FRED series ID, and an array of vintage date objects representing the dates on which data revisions for that series were released

## 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-dates-617082b2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
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