filter_unknown_field

Summary

unknown filter field `{0}`

Help

supported fields: name, src, or any defined label key

Details

When this fires

A filter string referenced a field that isn't name, src, or any label key registered on the resolver. The FilterResolver looked the key up, missed, and bailed.

What to check

name and src are the only built-ins. Label keys must be added with with_label (or via the adapter / collector config that owns this filter) before the filter runs. Filters operate on routing metadata, not metric values, so don't use metric paths like cpu.usage here.

# broken: no such field
filter = "host is \"web-1\""
# fixed: a registered label
filter = "env is \"prod\""

Surfaces during nanook check and at runtime. See @/docs/reference/dsl/filter.md.