# CoinCap Historical Price Data

> CoinCap Historical Price Data is a paid API for AI agents from rest.coincap.io, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Returns historical price series for a given cryptocurrency asset by slug

## Facts

- Endpoint: GET https://rest.coincap.io/v3/agentFriendly/history/%7Bslug%7D
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/coincap-historical-price-data-a4b1c52d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_5WuxIZtRoBb6gDE4GX7LV

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 coincap-historical-price-data-a4b1c52d
```

Example prompt: Can you pull the historical price history for bitcoin from CoinCap so I can see how it's trended over time?

## When to prefer this

Use this endpoint when you need historical price data for a specific cryptocurrency and want a simple time-series without derived indicators. If you need computed technical indicators like MACD, prefer the sibling MACD endpoint. Ideal for agents needing price history for backtesting, charting, or trend analysis without requiring account signup via the x402 per-call payment option.

## Known failure modes

- Invalid or unknown asset slug returns an error or empty dataset
- Missing slug parameter causes a 400 Bad Request
- Payment failure via x402 protocol results in 402 Payment Required with no data returned
- Rate limiting or authentication errors if API key is invalid or quota exceeded
- Network timeouts for assets with very large historical datasets

## How this service works

CoinCap gives AI agents, apps, and developers real-time cryptocurrency market data.

Two ways to access:
- **API key** — sign up at https://coincap.io and pass `Authorization: Bearer <key>` or `?apiKey=<key>`.
- **Keyless x402** (agents) — the 10 `agentFriendly` endpoints accept per-call USDC payment on Base via the [x402 protocol](https://x402.gitbook.io/x402). No signup needed. See `/.well-known/x402.json` for the machine-readable payment catalog.

## Output

A time-series dataset of historical price points for the requested cryptocurrency asset, including timestamps and corresponding price values in USD, capped to a certain number of data points.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "slug"
 ],
 "properties": {
  "slug": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/coincap-historical-price-data-a4b1c52d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from rest.coincap.io](https://www.zero.xyz/host/rest.coincap.io/llms.txt)