Command
nylas calendar availability check
Check participant availability for a time window.
Written by Qasim Muhammad Staff SRE
What does nylas calendar availability check do?
The nylas calendar availability check command queries free/busy data for one or more participants within a time window. Pass --start and --end as ISO 8601 timestamps and --emails as a comma-separated list of email addresses. Returns busy slots and free windows. Works with Google Calendar, Outlook, Exchange, Yahoo, iCloud, and IMAP providers.
Usage
nylas calendar availability check --start START --end END --emails EMAILSFlags
| Flag | Description |
|---|---|
| --json | Output as JSON |
| --no-color | Disable color output |
| --verbose(-v) | Enable verbose output |
| --config | Custom config file path |
| --help(-h) | Show help for the command |
| --limit | Limit results (most list commands) |
| --yes(-y) | Skip confirmations |
| --start | Start of time window (ISO 8601) |
| --end | End of time window (ISO 8601) |
| --emails | Comma-separated email addresses |
| --duration(-d) | Duration from start (e.g., '8h', '1d', '7d') |
Examples
The nylas calendar availability check command queries free/busy data for one or more participants within a time window.
Check if a slot is free for two people
nylas calendar availability check --start 2026-03-27T10:00:00Z --end 2026-03-27T11:00:00Z --emails alice@example.com,bob@example.comFind free windows in a day as JSON
nylas calendar availability check --start 2026-03-27T08:00:00Z --end 2026-03-27T18:00:00Z --emails team@example.com --jsonExample output
Availability 2026-07-01 09:00 - 2026-07-01 17:00
alice@example.com
busy 10:00-10:30
busy 14:00-15:00
bob@example.com
busy 11:00-11:30
Free for both: 09:00-10:00, 15:00-17:00Troubleshooting
Availability returns empty results
The participant's calendar may not share free/busy data. Google Workspace and Microsoft 365 support free/busy lookups by default; personal accounts may not.
Invalid time format error
Use ISO 8601 format: 2026-03-27T10:00:00Z. Include the timezone offset or Z for UTC.
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Run nylas calendar availability check --help for full help output.