CoinGecko API

Query cryptocurrency prices, market caps, charts, and trending tokens via the CoinGecko free API.

Base URL

https://api.coingecko.com/api/v3

No API key required. Rate limit: ~30 calls/minute.

Endpoints

Price Lookup

GET /simple/price?ids={ids}&vs_currencies={currencies}&include_24hr_change=true&include_market_cap=true

• ids: comma-separated CoinGecko IDs (see ID table below)
• vs_currencies: usd, btc, eth, bnb

Example: /simple/price?ids=bitcoin,ethereum&vs_currencies=usd&include_24hr_change=true

Token Price by Contract Address

GET /simple/token_price/{platform}?contract_addresses={addresses}&vs_currencies=usd&include_24hr_change=true

Platform IDs:

• binance-smart-chain — BSC
• ethereum — Ethereum
• polygon-pos — Polygon
• arbitrum-one — Arbitrum
• optimistic-ethereum — Optimism
• base — Base

Example: /simple/token_price/binance-smart-chain?contract_addresses=0x0E09FaBB73Bd3Ade0a17ECC321fD13a19e81cE82&vs_currencies=usd

Market Rankings

GET /coins/markets?vs_currency=usd&order=market_cap_desc&per_page=20&page=1&sparkline=false

Returns top coins with price, market cap, volume, and 24h change.

Trending

GET /search/trending

Returns trending coins, NFTs, and categories. No parameters needed.

Historical Chart

GET /coins/{id}/market_chart?vs_currency=usd&days={days}

• days: 1, 7, 14, 30, 90, 365, max
• Returns arrays of [timestamp, value] for prices, market_caps, total_volumes

Coin Detail

GET /coins/{id}?localization=false&tickers=false&community_data=false&developer_data=false

Returns full metadata: description, links, contract addresses, market data.

CoinGecko ID Reference

For unknown tokens, search: GET /search?query={name}

Usage Notes

• Always use curl -s to fetch, then parse the JSON response
• For on-chain token prices not listed on CoinGecko, fall back to DEX quotes via swap_get_quote
• The market-data skill provides high-level workflow guidance; this skill is the concrete API reference
• Report data source and freshness: "CoinGecko, fetched just now"