Nagios Crunchtools

Secure MCP server for Nagios Core monitoring. Query host and service status, acknowledge problems, add comments, schedule forced checks, and read notification history.

Installation

uvx mcp-nagios-crunchtools

Configuration

Variable	Required	Description
NAGIOS_URL	Yes	Base URL (e.g., https://nagios.example.com)
NAGIOS_USER	Yes	HTTP Basic Auth username
NAGIOS_PASS	Yes	HTTP Basic Auth password
NAGIOS_COMMENT_AUTHOR	No	Author recorded on acknowledgements and comments. Defaults to NAGIOS_USER. Not a tool parameter.
NAGIOS_CGI_PREFIX	No	Path under NAGIOS_URL where the CGI scripts are served. Defaults to /nagios/cgi-bin. Set to /cgi-bin for a Nagios served at the web root. A trailing slash is ignored.
NAGIOS_LOG_PATH	No	Read-only path to nagios.log. Enables nagios_downtime_history and the planned-work split in nagios_alert_history; archivejson.cgi never returns downtime entries.
TZ	Effectively yes	The container's local timezone. Must match the Nagios server's own timezone.

Why TZ matters

schedule_check submits a start_time to cmd.cgi, which parses it as naive wall-clock time in the Nagios server's local timezone — there is no offset field to send. The value is therefore built with time.localtime(), so this container must run in the same timezone as the Nagios server.

When it does not, forced checks are silently scheduled into the future by the offset between the two — four hours against an EDT server — and "check now" appears to do nothing at all. No error is raised. This was a real defect, fixed in 0.1.2 by switching from gmtime() to localtime(); the timezone assumption it introduced is why TZ belongs in this table rather than being left implicit.

Tools

Tool	Description
nagios_host_status	Query a single host's status
nagios_service_status	Query a single service's status
nagios_current_problems	All hosts/services not in OK state, with duration, attempt, acknowledgement and plugin output
nagios_program_status	Health check on the monitoring path itself (wedged daemon, disabled notifications, stale status) -- not the same as no current problems
nagios_acknowledge	Acknowledge a host or service problem
nagios_add_comment	Add a comment to a host or service
nagios_schedule_check	Force an immediate re-check
nagios_schedule_downtime	Fixed downtime from now (5–480 min) on a host and its services, or one service, before planned work
nagios_list_downtimes	Downtime in effect or pending
nagios_cancel_downtime	End this server's own downtime when the work is done
nagios_downtime_history	Past and current downtime windows with author and comment, from nagios.log
nagios_notification_history	Recent notifications
nagios_alert_history	State changes rolled up per host/service, including warnings and problems that recovered by themselves; problems during scheduled downtime are totalled separately

License

AGPL-3.0-or-later