Public OpenSky Network API (https://opensky-network.org/api). Live aircraft
state vectors and historical flight data collected from a worldwide network
of ADS-B receivers. No authentication required for the v1 endpoints; the
service applies per-IP rate limits (anonymous access is throttled, roughly
a handful of requests per minute on the time-window endpoints).
Generic CLI: query-based, no account. opensky states live shows aircraft
over a bounding box right now; opensky flights arrivals --airport KJFK
lists flights arriving at JFK in the default recent window (begin/end
default to now-2h..now via a local patch); opensky flights aircraft --icao24 <hex> replays one aircraft's trajectory.
Coordinates are WGS84 decimal degrees; airports are ICAO codes (KJFK, EGLL,
EDDF); timestamps are UNIX epoch seconds; icao24 is the 6-hex-digit
transponder address.
Created by @mvanhorn (Hunter Veltri).
Quick Start
1. Install
See Install above.
2. Verify Setup
opensky-pp-cli doctor
This checks your configuration.
3. Try Your First Command
opensky-pp-cli states
Unique Features
These capabilities aren't available in any other tool for this API.
flights get-departures --airport KJFK — begin/end default to the last hour on every /flights/* command (OpenSky requires the window and anonymous access caps it at 1h), so live queries work with zero epoch math. Override with --begin/--end.flights get-aircraft-trajectory --icao24 <hex> — OpenSky answers HTTP 404 with an empty array when a window has no flights; the CLI treats that as an empty result (exit 0) instead of the generic resource-not-found error.states --lamin 40.5 --lomin -74.5 --lamax 41.5 --lomax -73.5 — Live ADS-B state vectors over any bounding box with no API key; --icao24 filters to one transponder for a single-aircraft view.
Usage
Run opensky-pp-cli --help for the full command reference and flag list.
Paths & environment variables
This CLI separates local files into four path kinds:
| Kind | Contents |
|---|
config | User-editable settings such as config.toml and saved profiles |
data | Durable local data such as data.db |
state | Runtime state such as persisted queries, jobs, and teach.log |
cache | Regenerable HTTP/cache files |
Each kind resolves independently. The ladder is:
- Per-kind env var:
OPENSKY_CONFIG_DIR, OPENSKY_DATA_DIR, OPENSKY_STATE_DIR, or OPENSKY_CACHE_DIR
--home <dir> for this invocationOPENSKY_HOME for a flat relocated root- XDG env vars:
XDG_CONFIG_HOME, XDG_DATA_HOME, XDG_STATE_HOME, XDG_CACHE_HOME
- Platform defaults matching existing installs
For containers and agent sandboxes, prefer a single relocated root:
export OPENSKY_HOME=/srv/opensky
opensky-pp-cli doctor
Under OPENSKY_HOME=/srv/opensky, the four dirs resolve to /srv/opensky/config, /srv/opensky/data, /srv/opensky/state, and /srv/opensky/cache.
MCP servers do not receive CLI flags from the host. Put relocation in the host env block:
{
"mcpServers": {
"opensky": {
"command": "opensky-pp-mcp",
"env": {
"OPENSKY_HOME": "/srv/opensky"
}
}
}
}
Precedence matters in fleets: an ambient per-kind variable such as OPENSKY_DATA_DIR overrides an explicit --home for that kind. Use OPENSKY_HOME or the per-kind variables for durable fleet relocation; treat --home as the weaker per-invocation lever.
Relocation is one-way. Unsetting OPENSKY_HOME does not move files back to platform defaults, and doctor cannot find files left under a former root. Move the files manually before unsetting relocation variables.
Existing installs keep working because the platform-default rung matches the legacy layout. Run opensky-pp-cli doctor --fail-on warn to check path warnings in automation.
Commands
flights
Manage flights
opensky-pp-cli flights get-aircraft-trajectory - Full trajectory for one aircraft within a time windowopensky-pp-cli flights get-departures - Flights departing an airport within a time window
states
Manage states
opensky-pp-cli states - Live aircraft states over a bounding box or for one transponder
Self-learning loop
This CLI caches per-question discovery so repeat queries skip the walk and structurally similar queries get answered via entity substitution. The loop also self-captures: every invocation is journaled locally, and failed-flag corrections plus fresh teaches surface as candidates on the next recall for confirm/reject judgment. Agents call recall before discovery and fire teach & after answering. See the ## Automatic learning section in SKILL.md for the full protocol.
opensky-pp-cli recall <query> - Look up cached resources for a query before running discoveryopensky-pp-cli teach - Record a query -> resource mapping (silent on success, safe to background with &)opensky-pp-cli learnings list - Inspect taught rowsopensky-pp-cli learnings forget <query> - Undo a teachopensky-pp-cli learnings candidates - List auto-captured candidates awaiting confirm/rejectopensky-pp-cli learnings stats - Local loop metrics: recall hit rate, teach-to-reuse, playbook resolution, candidate countsopensky-pp-cli teach-pattern - Install a query/resource template up frontopensky-pp-cli teach-lookup - Add an entity mapping (e.g. country code, team alias) for pattern substitution
Pass --no-learn or set OPENSKY_NO_LEARN=true to disable the loop for deterministic flows.
The local store's schema version stamp is one-way: once this version of opensky-pp-cli opens the database, older binaries refuse it with a version error — upgrade the binary rather than downgrading.
Output Formats
# Human-readable table (default in terminal, JSON when piped)
opensky-pp-cli states
# JSON for scripting and agents
opensky-pp-cli states --json
# Filter to specific fields
opensky-pp-cli states --json --select id,name,status
# Dry run — show the request without sending
opensky-pp-cli states --dry-run
# Agent mode — JSON + compact + no prompts in one flag
opensky-pp-cli states --agent
Agent Usage
This CLI is designed for AI agent consumption:
- Non-interactive - never prompts, every input is a flag
- Pipeable -
--json output to stdout, errors to stderr
- Filterable -
--select id,name returns only fields you need
- Previewable -
--dry-run shows the request without sending
- Read-only by default - this CLI does not create, update, delete, publish, send, or mutate remote resources
- Offline-friendly - sync/search commands can use the local SQLite store when available
- Agent-safe by default - no colors or formatting unless
--human-friendly is set
Exit codes: 0 success, 2 usage error, 3 not found, 5 API error, 7 rate limited, 10 config error.
Health Check
opensky-pp-cli doctor
Verifies configuration and connectivity to the API.
Configuration
Run opensky-pp-cli doctor to see the resolved config, data, state, and cache directories. The platform-default config path is ~/.config/opensky-network-pp-cli/config.toml; --home, OPENSKY_HOME, and per-kind env vars can relocate it.
Static request headers can be configured under headers; per-command header overrides take precedence.
Troubleshooting
Not found errors (exit code 3)
- Check the resource ID is correct
- Run the
list command to see available items
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