Flight Tracker Skill

"Where's that flight right now?" has a genuinely open answer: hobbyist ADS-B receiver networks share live aircraft transponder data keylessly — adsb.lol serves it clean, OpenSky backs it up. This skill queries by callsign, hex, or area, and translates transponder math into human answers ("over Poland at 38,000 ft, ~40 minutes from Warsaw-ish airspace"). It's equally honest about the boundary: this is positions, not airline operations — gate changes, delays, and cancellations live in keyed commercial services, and pretending otherwise produces confident fiction.

What This Skill Produces

• The position — where the aircraft is now: location in words, altitude, ground speed, heading, climb/descent
• The overhead list — aircraft above/near a point, sorted by distance
• The interpretation — cruise vs. descent, direction of travel, rough progress — labeled as inference from position data
• The command — exact curl, rerunnable — and the boundary line when the question was schedule-shaped

Required Inputs

Ask for these if not provided:

• The identifier — callsign (what ATC uses: BAW123, often ≈ flight number with the airline's ICAO prefix — BA→BAW, LH→DLH, UA→UAL; do the mapping and say so), registration/tail number, or ICAO hex
• Or the place — lat/lon for "what's overhead" questions, with a radius
• What they actually want — position/curiosity vs. "is it delayed / when does it land" — the second gets the honest redirect plus what positions can infer

Framework: The Network and the Boundary

1. adsb.lol — primary: by callsign: curl -s "https://api.adsb.lol/v2/callsign/BAW123" · by registration: .../v2/reg/G-XLEB · by hex: .../v2/hex/4075a2 · overhead: .../v2/lat/51.5/lon/-0.12/dist/25 (nm). Fields per aircraft: flight (callsign), alt_baro (ft), gs (knots), track (° heading), baro_rate (ft/min climb/descent), lat/lon, t (type).
2. OpenSky — fallback: curl -s "https://opensky-network.org/api/states/all?lamin=51.4&lamax=51.6&lomin=-0.4&lomax=0.2" — anonymous access, tighter rate limits; state vectors as positional arrays (index 1 callsign, 5/6 lon/lat, 7 baro alt m, 9 velocity m/s). Units differ between the two (ft/knots vs. m and m/s) — convert deliberately, never mix.
3. Interpret the physics: baro_rate near 0 at 35,000+ ft = cruise; sustained −1,500 ft/min = descent (landing within ~30–45 min, framed as an estimate); track + position = direction in words ("heading east over Poland"). All labeled inference.
4. Coverage honesty: ADS-B networks depend on volunteer ground receivers — coverage is excellent over Europe/NA, patchy over oceans and parts of Africa/Asia. "Not found" means not currently received or not airborne, and the answer says both possibilities, not "the flight doesn't exist."
5. The schedule boundary: delays, gates, cancellations, scheduled times → keyed services (airline apps, FlightAware/FR24) — name them, don't fake them. What positions legitimately infer (airborne yes/no, descent begun, rough progress) is offered as the keyless consolation, labeled as inference.

Output Format

Flight: [callsign/reg] — [fetch time]

[The answer: "Airborne — over [area] at [alt] ft, [speed] kn, heading [direction]; descending, likely landing within ~[range]." or the honest not-received line.]

[Overhead mode: table sorted by distance]

Source: [adsb.lol / OpenSky] community ADS-B · as of [time] · rerun: [exact curl] [Schedule-shaped questions: the boundary line + what position data can and can't infer]

Quality Checks

• Flight numbers were mapped to ICAO callsigns with the mapping shown
• Units are consistent and stated (the two sources differ)
• Inferences (descent, ETA-ish) are labeled as inferences from position
• "Not found" answers include the coverage explanation, both possibilities
• Schedule questions get the honest boundary, not improvised delay data

Anti-Patterns

• Do not fake schedule data — delays and gates are not in ADS-B, and confident fiction here strands people
• Do not mix the two sources' units — a 10,000 m cruise is not a 10,000 ft one
• Do not present patchy coverage as "flight doesn't exist"
• Do not track people — flights and public transponder data, not persistent monitoring of individuals' movements
• Do not answer from memory — a remembered aircraft position is nonsense by construction