* Add fields param to search_code and get_file_contents
Add an optional `fields` array parameter to the `search_code` and
`get_file_contents` tools so callers can request only the fields they
need, reducing tool response size and context usage.
- search_code: filters each result item to the selected fields while
preserving the total_count / incomplete_results wrapper.
- get_file_contents: filters each directory entry when listing a
directory; ignored for single-file responses.
Adds shared filterFields / filterEachField helpers and per-tool field
enums, plus unit tests and regenerated toolsnaps and docs.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
* Gate fields param behind fields_param flag and add usage telemetry
Register search_code and get_file_contents as two mutually exclusive
variants gated by the new `fields_param` feature flag, following the
existing dual-variant flag pattern:
- The flag-enabled variant advertises the optional `fields` parameter and
filters each result to the requested subset. It owns the
`<tool>_ff_fields_param` toolsnap.
- The Legacy* variant exposes the original schema with no `fields`
parameter and never filters, acting as a kill switch when the flag is
off. It owns the canonical toolsnap.
Add best-effort, low-cardinality telemetry at each tool's filter point to
measure adoption and realized savings:
- `mcp.fields.tool_call` (increment) tagged by tool and whether the
response was filtered.
- `mcp.fields.bytes_full` / `bytes_sent` / `bytes_saved` (counters) tagged
by tool, emitted only when a response was filtered.
Tags are limited to `tool` and `filtered` to bound cardinality; repo,
owner, user, query, and the requested field list are never tagged. The
local server discards these via the noop metrics sink, while hosted
deployments inject a real sink. Metrics accessors now fall back to a noop
sink when no exporter is configured so emitting telemetry never panics.
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
* Drop mcp.fields.bytes_saved metric
Remove the mcp.fields.bytes_saved counter. It is derivable on the
dashboard from the two remaining byte counters, since
sum(bytes_full) - sum(bytes_sent) equals the total saved at any rollup,
so emitting it separately is redundant. Keeping only bytes_full and
bytes_sent shrinks the emitted telemetry surface.
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
---------
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Tommaso Moro