Most fantasy sports side-projects start the same way: scrape ESPN, parse HTML, watch it break the next time their markup changes. An API skips that failure mode entirely — but picking the right one matters more than picking any one.
What you actually need, in order
- Player and team identity — a stable ID per player that doesn't shift week to week. This is the foundation everything else joins against.
- Games and live state — scheduled, in-progress, final — so your app knows when to poll vs. cache.
- Injury/news signals — this is what actually drives engagement in a fantasy app; "Player X questionable for Sunday" is the notification people open the app for.
- A confidence or projection layer — optional, but it's the difference between an app that shows data and one that gives advice.
A minimal first call
curl https://playcallerapp.com/v1/intelligence/news \
-H "X-PlayCaller-Key: pc_live_your_key_here" \
-G -d "severity=high&limit=5"That single call returns structured injury/news signals — player, team, signal type, severity, a plain-English title, and (where relevant) which other players benefit from the change. That last field — beneficiaries — is the kind of thing that's genuinely tedious to derive yourself from raw box scores, and it's the kind of detail that makes a fantasy app feel smart rather than just data-dense.
Where to stop building it yourself
Confidence scoring is the part most side-projects either skip or fake with a heuristic. If you want a real one, look for a published validation number (AUC-ROC, decile lift) before trusting it — and treat "we use AI" as a marketing phrase, not a measurement, unless the provider shows you the number.
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