crypto-prices

Crypto Prices Skill

Crypto prices are the most-asked live number after weather, and two services answer keylessly: CoinGecko's public API (thousands of coins, market context, any quote currency) and Coinbase's spot endpoint (fast, reliable, majors only). This skill fetches, adds the 24-hour context that turns a number into information, and carries the caveat every crypto answer owes: this number is already stale, and it is not advice.

What This Skill Produces

• The price — stated first, in the asked currency, with 24h change alongside
• Context — 24h high/low or market-cap rank when the question implies "how's it doing"
• The command — exact curl, rerunnable
• The caveat — timestamped, volatile, informational-only

Required Inputs

Ask for these if not provided:

• The coin(s) — resolve names to CoinGecko ids (bitcoin, ethereum, solana…); for obscure tickers, search first: https://api.coingecko.com/api/v3/search?query=name — ticker collisions are common and the wrong coin is a real failure mode
• Quote currency — usd default, but honor the user's (CoinGecko quotes in dozens: vs_currencies=eur,inr,jpy)
• Depth — a number, or market context (change, volume, rank)?

Framework: The Two Sources

1. CoinGecko — primary: simple price: curl -s "https://api.coingecko.com/api/v3/simple/price?ids=bitcoin,ethereum&vs_currencies=usd&include_24hr_change=true&include_24hr_vol=true&include_last_updated_at=true" · richer context: .../api/v3/coins/markets?vs_currency=usd&ids=bitcoin,ethereum (adds rank, high/low, ATH distance) · trending: .../api/v3/search/trending. Public tier rate-limits (~10–30 req/min) — batch ids into one call, never loop.
2. Coinbase — fallback for majors: curl -s "https://api.coinbase.com/v2/prices/BTC-USD/spot" — extremely reliable, majors and USD/EUR/GBP pairs, no market context. Use when CoinGecko rate-limits or for a fast single number.
3. Timestamp every answer: include include_last_updated_at and print it; crypto moves percent-per-hour on bad days, and an undated price is misinformation waiting to age.
4. Context is the value-add: "$63,977, down 2.1% in 24h" answers "how's bitcoin"; the bare price doesn't. For "how's the market," compare BTC + ETH + a top-alt rather than editorializing.
5. The line that never moves: prices are informational; no buy/sell/hold, no predictions, no portfolio math presented as guidance. "Is now a good time to buy" gets the price, the volatility fact, and a clean refusal to predict.

Output Format

[Coin] Price

[Price] [currency] · 24h: [±x.x%] [· rank/context if asked]

[Multi-coin questions: small table, one row per coin]

Source: [CoinGecko / Coinbase] at [timestamp, UTC] · rerun: [exact curl]

Live snapshot, already aging — informational only, not investment advice.

Quality Checks

• [ ] The coin id was resolved unambiguously (searched when the ticker could collide)
• [ ] 24h change accompanies the price
• [ ] The timestamp appears in the answer
• [ ] Multi-coin requests were batched into one call
• [ ] The not-advice line appears verbatim in spirit — every time

Anti-Patterns

• [ ] Do not answer from memory — a remembered crypto price is fiction; fetch or hand over the command
• [ ] Do not guess which coin a ticker means — search and confirm; $PEPE-class collisions burn people
• [ ] Do not loop per-coin requests against a rate-limited public API — batch
• [ ] Do not predict, recommend, or imply timing — the refusal is part of the skill
• [ ] Do not quote without the timestamp — undated crypto prices are misinformation with confidence