check_index_coverage reports coverage_unavailable for indexed paths when ignored records truncate #1613

Version

codebase-memory-mcp 0.10.2

Platform

macOS (Apple Silicon)

Install channel

GitHub release archive / install.sh / install.ps1

Binary variant

standard

What happened, and what did you expect?

When discovery sees more than 2,000 deliberately ignored files, coverage metadata records recording_status: "truncated". That global state makes check_index_coverage return coverage_unavailable for an unrelated source file that was successfully indexed, has a current file-hash record, and reports freshness: "metadata_match".

The source remains searchable in the graph; only the by-design not_indexed_file catalogue was truncated. A directory-level .cbmignore is a workaround because it collapses thousands of file rows into one excluded-subtree row, but unrelated indexed code should remain usable without repository-specific asset exclusions.

Current result:

{
  "requested_path": "main.go",
  "status": "coverage_unavailable",
  "freshness": "metadata_match",
  "coverage": []
}

Expected result for that exact, fresh, indexed file:

{
  "requested_path": "main.go",
  "status": "no_recorded_issue",
  "freshness": "metadata_match",
  "coverage": []
}

Explicit partial, skipped, and excluded rows must continue to win. Stale generations, changed/missing file metadata, lookup failures, and truncated empty scope queries must remain coverage_unavailable.

Root cause in coverage_status:

if (!generation_matches || !recording_status ||
    strcmp(recording_status, "complete") != 0) {
    return "coverage_unavailable";
}

This conflates exact-file indexedness/freshness with completeness of the unrelated ignored-file catalogue.

Related: #1356 covers output size/capped counts and documents the .cbmignore workaround. #963/#974 introduced the by-design coverage class and 2,000-entry cap. This report is specifically about the exact-path semantic false negative.

Reproduction

1. Create a temporary repository with one normal source file:

   package main
   
   func main() {}

2. Add 2,001 empty files named assets/0001.png through assets/2001.png. Do not add a directory-level .cbmignore.

3. Run a full index:

   codebase-memory-mcp cli index_repository --repo-path "$PWD" --mode full --name coverage-truncation-repro

4. Call the MCP tool:

   {
     "project": "coverage-truncation-repro",
     "paths": ["main.go"]
   }

5. Observe metadata equivalent to:

   {
     "recording_status": "truncated",
     "ignored_files_stored": 2000,
     "ignored_files_total": 2001,
     "hash_records_complete": true,
     "generation_matches": true
   }

   The exact path incorrectly returns coverage_unavailable despite freshness: "metadata_match" and a current file-hash record. It should return no_recorded_issue.

The reproduction uses generated empty image files and a minimal dummy source file; no proprietary code or logs are involved.

Logs

Diagnostics trajectory (memory / performance / leak issues)

Project scale (if relevant)

No response

Confirmations

• I searched existing issues and this is not a duplicate.
• My reproduction uses shareable code (a dummy snippet or a public OSS repository), not proprietary code.