# Fathom Macroeconomic Data API — Observations

> Fathom Macroeconomic Data API — Observations is a paid API for AI agents from fathoms.vercel.app, paid per call via x402, $0.06/call, status unknown (last checked 2026-09-15).

Fetches time-series observations for any FRED economic indicator (GDP, inflation, unemployment, interest rates, etc.) with flexible date ranges, frequency, and unit transformations

## Facts

- Endpoint: POST https://fathoms.vercel.app/api/observations
- Price: $0.06/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-observations-69f082d1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hhGVLFZDZhDHZqUOgRYjm

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-observations-69f082d1 -d '<json body>'
```

Example prompt: Pull the monthly US CPI inflation data (CPIAUCSL) from FRED for January 2020 through December 2023, sorted oldest to newest, and give me up to 50 observations in percent change from a year ago.

## When to prefer this

Choose this endpoint when you need programmatic access to any of FRED's 816,000+ macroeconomic time series — especially GDP, CPI, unemployment, interest rates, and monetary aggregates — with control over date range, frequency aggregation, and unit transformation. Prefer this over direct FRED API access when you want a simpler POST interface with x402 micropayment support and no FRED API key management.

## Known failure modes

- Invalid or unknown FRED series ID returns an error or empty observations array
- Malformed date strings cause bad request errors
- Requesting too many observations may result in truncated or slow responses
- Invalid units or frequency codes may be rejected or silently ignored
- Network or Vercel deployment timeouts if FRED upstream is slow

## 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 FRED series ID, data source label, total observation count, and an array of observation objects each with a date and value. The array is ordered by the requested sort direction and capped at the requested limit.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "seriesId"
 ],
 "properties": {
  "end": {
   "type": "string",
   "description": "End date YYYY-MM-DD"
  },
  "sort": {
   "type": "string",
   "description": "Sort order: asc or desc (default: desc)"
  },
  "limit": {
   "type": "string",
   "description": "Max observations (default: 10)"
  },
  "start": {
   "type": "string",
   "description": "Start date YYYY-MM-DD"
  },
  "units": {
   "type": "string",
   "description": "Units transformation (lin, chg, ch1, pch, pca, cch, cca, log)"
  },
  "seriesId": {
   "type": "string",
   "description": "FRED series ID (e.g. GDP, UNRATE, CPIAUCSL)"
  },
  "frequency": {
   "type": "string",
   "description": "Frequency (d, w, bw, m, q, sa, a)"
  }
 }
}
```

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fathom-macroeconomic-data-api-observations-69f082d1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fathoms.vercel.app](https://www.zero.xyz/host/fathoms.vercel.app/llms.txt)