Last modified June 21, 2026
'muster call' command reference
muster call invokes any MCP tool by name, including the core_* tools, the x_* tools from aggregated servers, and the workflow_* tools. The aggregator must be running, or --endpoint must point at a remote one.
Usage
muster call <tool-name> [--arg=value ...]
Pass arguments as --key=value or --key value flags. To pass a structured argument, use --json with a JSON object instead.
Flags
| Name | Description |
|---|---|
--json | Pass the tool arguments as a single JSON object |
Any other --key=value flag is forwarded to the tool as an argument. call also accepts the common flags.
Examples
muster call core_service_list
muster call core_service_status --name=prometheus
muster call workflow_deploy --environment=production --replicas=3
muster call core_mcpserver_list --output json
Related
- Meta-tools - The tool families and the
core_*catalog. muster start- Run a workflow by name.
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