unknown_metric
Diagnostic `nanook::cli::unknown_metric`
Summary
unknown metric `{0}`
Help
no registered collector emits {0}; check for typos
Details
When this fires
nanook check saw a metric selector that doesn't appear in the inventory of any registered collector, builtin or plugin. Not just "no configured collector emits it", literally nothing in the registry knows about it. Almost always a typo.
What to check
Compare against nanook doc collectors for canonical names. If the metric comes from a plugin, the registry only sees it after PluginHost::install succeeds, so confirm the plugin loads cleanly under [plugins].dirs.