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@@ -100,6 +100,27 @@ not respect `--lectionary`/`--offline`, it always harvests the modern
 lectio update --days 30
 ```
 
+### Calendar API — JSON & iCal
+
+Emit the computed liturgical calendar (day identity + reading citations) as
+JSON or iCal, offline. Honours the config's form (OF/EF) and custom calendar
+layers.
+
+```sh
+lectio 2026-01-06 --format json                       # one day, JSON
+lectio --format ical --year 2026 > lectio-2026.ics    # a year, iCal feed
+lectio --format json --from 2026-01-01 --to 2026-01-31 # a range
+lectio --format ical --year 2026 --form new           # override the form
+```
+
+`lectio-web` also serves the same data for `webcal://` subscription:
+
+- `GET /api/calendar.json?date=…` or `?from=&to=` or `?year=` (+ optional `&form=old|new`)
+- `GET /calendar.ics?year=…` or `?from=&to=` — served as `text/calendar`
+
+The web endpoints validate every input and cap a request's span at ~5 years
+(1830 days); JSON carries a stable `"schema": "lectio.calendar/1"`.
+
 ## `lectio-ui` — the terminal reader
 
 ```sh