Crypto Sentiment API

Track how 30 major cryptocurrencies are being talked about right now — sentiment scores, mention volume, and momentum signals distilled from live crypto news.

Crypto Sentiment continuously ingests headlines from a dozen leading crypto news feeds, scores every mention with VADER sentiment analysis, and aggregates the results per coin. For each token you get a compound sentiment score, a positive/neutral/negative breakdown, raw mention counts, and a velocity-based momentum signal (SPIKE / RISING / FALLING / STABLE) computed against the prior hour. A /trending endpoint ranks the coins generating the most accelerating chatter so you can spot narrative shifts as they happen.

Endpoints

Endpoint	What it returns
`GET /sentiment/{coin}`	Full sentiment snapshot for one coin (symbol, e.g. `BTC`). Returns `coin`, `sentiment_score` (compound, −1 to 1), `breakdown` (`positive`/`neutral`/`negative` as shares of mentions), `mention_count`, `velocity` (e.g. `"+34%"`), `signal` (`SPIKE`/`RISING`/`FALLING`/`STABLE`), `sources` (`reddit`, `news` counts), and `updated_at`.
`GET /trending`	Coins ranked by mention velocity, highest first. Returns `updated_at` and a `coins` array of `{coin, sentiment_score, velocity, signal, mention_count}`. Optional `limit` query param (1–30, default 10). Only coins with real mentions appear.
`GET /coins`	Static reference list of the 30 supported coin symbols (`coins` array). No auth required.
`GET /health`	Liveness check. Returns `status` and `updated_at` (timestamp of the most recent scrape). No auth required.

Why this API

Real news, not a black box. Sentiment is built from public headlines and summaries across 12 established crypto outlets (CoinDesk, Cointelegraph, Decrypt, The Block, CryptoSlate, NewsBTC, Bitcoinist, U.Today, CoinJournal, Bitcoin Magazine, CoinGape, CryptoBriefing), scored with the open VADER lexicon — the methodology is transparent and reproducible.
Momentum, not just a static score. Each coin carries a velocity figure and a discrete signal derived from how its mention volume changed versus an hour ago, so you can distinguish a quiet coin from one whose narrative is suddenly accelerating.
Ranked trending feed. /trending surfaces the coins with the fastest-growing discussion and automatically suppresses un-discussed (zero-mention) tokens, so the list is always actionable.
30 majors, alias-aware matching. Covers BTC, ETH, SOL, XRP, DOGE and 25 more, matching by name, ticker, and $-tag aliases (e.g. "bitcoin", "btc", "$btc") so mentions aren't missed on phrasing.
Simple, flat JSON. Predictable field names and small payloads — drop it straight into a dashboard, bot, or alerting rule with no parsing gymnastics.

Typical use cases

Power a market dashboard widget showing per-coin sentiment and a trending-narratives panel.
Drive alert rules — e.g. notify when a coin flips to a SPIKE signal or sentiment turns sharply negative.
Add a sentiment feature to a trading bot or backtest alongside price and volume data.
Monitor reputation and news momentum for a specific token you hold or cover.
Surface "what crypto is people talking about right now" rankings in a content or research product.

Good to know

Supported coins are fixed. /sentiment/{coin} accepts only the 30 symbols returned by /coins (case-insensitive). Anything else returns 404. Use /coins to enumerate the valid set.
Data is refreshed in cycles, not real-time per request. A background scraper runs on an interval (default every 15 minutes) and the API serves the latest cached snapshot. The updated_at field tells you how fresh the data is; check /health for the most recent cycle time.
News-driven by default. In production the pipeline runs in RSS-only mode — Reddit ingestion exists in the codebase but is disabled by default because Reddit's free Data API is non-commercial, so the sources.reddit count will typically be 0 and sources.news carries the signal.
Velocity needs history to warm up. velocity and signal compare current mention volume to roughly one hour earlier; immediately after a cold start (no prior history), velocity reads 0% and the signal is STABLE until enough cycles accumulate.
Sentiment is lexicon-based. Scores come from VADER applied to headline + summary text, aggregated across all matching articles in the current window. It reflects news tone, not price prediction, and a low mention_count means the score is based on few articles.
503 before first data. A supported coin that hasn't been scored yet returns 503 {"error": "data not yet available"} rather than empty data — retry once a cycle has run.
Access is via RapidAPI. Requests to the sentiment and trending endpoints are gated behind the RapidAPI proxy; /coins and /health are open.