feat: node role classification + dead code detection

[carlos-alm]

Summary

• Node role classification: Every symbol auto-tagged as entry/core/utility/adapter/dead/leaf based on fan-in/fan-out connectivity patterns with adaptive median thresholds
• Dead code detection: codegraph roles --role dead -T surfaces unreferenced non-exported symbols — delivered as a byproduct of classification
• New roles CLI command with --role, --file, and --no-tests filters
• New node_roles MCP tool (18 tools total)
• Roles surfaced across existing commands: where, explain, context, stats, list-functions now show [role] tags
• DB migration v5: adds role column + index to nodes table
• Docs updated: README (features, comparison tables, commands), BACKLOG (ID 1 + ID 4 marked DONE), COMPETITIVE_ANALYSIS (codegraph moved feat: multi-repo MCP with global registry (Phase 2.5) #16 → feat: Rust core engine via napi-rs (Phase 1) #8, score 3.8 → 4.0)

Also includes prior commits on this branch:

• fix(builder): preserve structure data during incremental builds
• perf(builder): avoid disk reads for line counts during incremental rebuild

Test plan

• Unit tests: tests/unit/roles.test.js — classification logic, median thresholds, idempotency, empty graph, file/directory nodes stay null
• Integration tests: tests/integration/roles.test.js — rolesData filters, statsData role distribution, whereData/explainData/listFunctionsData include role field
• MCP tests: tests/unit/mcp.test.js — updated with node_roles tool and rolesData mock
• Full test suite passes (509 tests, 0 failures)
• codegraph build . succeeds with roles computed
• codegraph roles -T shows role distribution
• Lint clean (biome)

[claude]

Claude finished @carlos-alm's task —— View job

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Reviewing PR #91: Incremental Build Structure Fix

Todo List:

• Read and analyze the changed code in src/builder.js
• Perform root cause analysis of the incremental build issue
• Check for risky configuration changes
• Verify test integrity and coverage
• Assess code quality and potential issues
• Provide final rating and recommendation

Root Cause Analysis

Problem Being Solved: During incremental builds, buildStructure() clears all contains edges and directory nodes (lines 35-40 in structure.js), but only receives changed files in the fileSymbols map. This caused codegraph structure to show "0 files, 0 symbols" for most directories because the complete file set wasn't available for structure rebuilding.

Why This Approach: The fix loads all existing file nodes from the database during incremental builds, ensuring buildStructure() has access to the complete file set. This is necessary because structure analysis requires ALL files to compute directory metrics and containment relationships correctly.

Risk Assessment: ✅ LOW RISK - This is a legitimate fix addressing a real functional bug, not masking symptoms.

Critical Concerns

None found. This is a clean, targeted fix.

Code Quality Assessment

✅ Strengths

1. Root Cause Fix: Addresses the actual problem (incomplete file set during structure rebuild) rather than symptoms
2. Performance Conscious: Only loads data for incremental builds (if (!isFullBuild))
3. Efficient DB Queries: Uses specific prepared statements to load only necessary data
4. Proper Error Handling: File reads are wrapped in try-catch blocks
5. Good Logging: Includes debug output showing how many files were loaded from DB
6. Maintains Data Integrity: Ensures both fileSymbols and lineCountMap are complete

✅ Technical Correctness

• SQL queries are correct and safe (no injection risks)
• Proper use of relative paths and normalization
• Handles missing files gracefully with try-catch
• Updates both required data structures consistently

✅ No Risky Changes

• No configuration changes detected
• No test modifications to make failing tests pass
• No linting rules disabled or relaxed
• No dependency changes

✅ Test Coverage

• All 491 tests pass (as stated in PR description)
• Lint clean
• Test plan includes both full and incremental build verification

🔍 Minor Observations

1. File Read Performance: Lines 855-862 read files synchronously from disk even though content might already exist in memory. However, this only affects incremental builds and the performance impact is acceptable.

2. Memory Usage: Loading all file symbols into memory increases memory footprint during incremental builds, but this is necessary for correct structure analysis.

Final Assessment

This is a well-executed bug fix that properly addresses the root cause of structure data loss during incremental builds. The implementation is clean, efficient, and follows the codebase's established patterns.

Final Recommendation

• Rating: ⭐⭐⭐⭐☆ (4/5)
• Action: APPROVE
• Reasoning: Solid bug fix with proper root cause analysis, clean implementation, no risky changes, and comprehensive testing. The only reason it's not 5 stars is that it's a straightforward fix rather than exceptional engineering.

Recommended Actions: None. The PR is ready to merge.

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[greptile-apps]

Greptile Summary

This PR fixes a critical bug where incremental builds corrupted directory structure data. The issue occurred because buildStructure() deletes all contains edges before rebuilding, but was only given changed files during incremental builds, causing most directories to show "0 files, 0 symbols".

Key Changes

• Loads all existing file nodes from DB before calling buildStructure during incremental builds
• Caches line counts from node_metrics table to avoid reading unchanged files from disk (performance optimization)
• Falls back to disk reads when cached line counts are unavailable
• Creates stub imports array with correct length using COUNT(DISTINCT n2.file) query

Performance Impact

The fix adds ~34ms to 1-file incremental rebuilds (+27%) due to loading 98 unchanged files' metadata from the DB. This is an acceptable trade-off for correct structure data, as the overhead is O(n) DB reads which will be dominated by parse time at scale.

Documentation Updates

• Added Phase 4b to dogfooding skill requiring performance benchmarks for PRs touching critical files
• Includes comprehensive dogfood report documenting the bug, fix, and all test results

Confidence Score: 5/5

• This PR is safe to merge with minimal risk
• The fix is well-targeted and addresses the root cause correctly. The developer addressed previous review feedback by replacing wasteful importsByFile query with a COUNT query and caching line counts from the node_metrics table. All 491 tests pass, benchmark results show acceptable performance trade-offs, and the changes are isolated to incremental build logic.
• No files require special attention

Important Files Changed

Filename	Overview
src/builder.js	Adds incremental build fix to preserve structure data by loading all existing files from DB before rebuilding contains edges
.claude/skills/dogfood/SKILL.md	Documents new performance benchmarks phase for dogfooding process, requires benchmark comparison for PRs touching critical files
generated/DOGFOOD_REPORT_v2.3.0.md	Generated dogfooding report documenting the incremental structure bug and its fix with benchmark results

_{Last reviewed commit: 7b538bc}

[greptile-apps]

_{1 file reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

Query returns files that the current file imports FROM (targets), but stores them as if they were import sources. The column is aliased as source but n2.file is the target of the import edge (the file being imported), not the source.

Expected structure based on buildStructure usage (line 129 in structure.js): imports: [{ source: './b.js', names: [] }]

This query returns target files instead of reconstructing the import structure. Should either:

1. Return the import source paths as strings (matching parser output format), or
2. Query should be n1.name AS source if storing the imported symbol names

Suggested change

	`SELECT DISTINCT n2.file AS source FROM edges e
	JOIN nodes n1 ON e.source_id = n1.id
	JOIN nodes n2 ON e.target_id = n2.id
	WHERE n1.file = ? AND e.kind = 'imports'`,
	const importsByFile = db.prepare(
	`SELECT DISTINCT e.*, n1.name AS imported_name, n2.file AS imported_from
	FROM edges e
	JOIN nodes n1 ON e.target_id = n1.id
	JOIN nodes n2 ON e.target_id = n2.id
	WHERE e.source_id IN (SELECT id FROM nodes WHERE file = ?) AND e.kind = 'imports'`,
	);

However, buildStructure only uses imports.length (line 129 in structure.js), so the current approach works for metrics calculation but doesn't preserve the actual import structure.

[carlos-alm]

Addressed Greptile feedback in 7b538bc:

1. Replaced importsByFile query with importCountByFile COUNT query — buildStructure only uses imports.length for the import_count metric (line 129 of structure.js), so fetching full rows was wasteful. Now uses SELECT COUNT(DISTINCT n2.file) and creates imports: new Array(importCount) for the correct .length.

2. Cached line counts from node_metrics table instead of reading every unchanged file from disk — eliminates ~98 synchronous readFileSync calls during incremental rebuilds on this repo. Falls back to disk read if no cached value exists.

[claude]

Claude finished @carlos-alm's task —— View job

---

Reviewing PR #91: Incremental Build Structure Fix

Todo List:

• Read and analyze the changed code in src/builder.js
• Perform root cause analysis of the incremental build issue
• Check for risky configuration changes
• Verify test integrity and coverage
• Assess code quality and potential issues
• Provide final rating and recommendation

Root Cause Analysis

Problem Being Solved: During incremental builds, buildStructure() clears all contains edges and directory nodes (lines 35-40 in structure.js), but only received changed files in the fileSymbols map. This caused codegraph structure to show "0 files, 0 symbols" for most directories because the complete file set wasn't available for structure rebuilding.

Why This Approach: The fix loads all existing file nodes from the database during incremental builds, ensuring buildStructure() has access to the complete file set. This is necessary because structure analysis requires ALL files to compute directory metrics and containment relationships correctly.

Risk Assessment: ✅ LOW RISK - This is a legitimate fix addressing a real functional bug, not masking symptoms.

Critical Concerns

None found. This is a clean, targeted fix.

Code Quality Assessment

✅ Strengths

1. Root Cause Fix: Addresses the actual problem (incomplete file set during structure rebuild) rather than symptoms
2. Performance Conscious: Only loads data for incremental builds (if (!isFullBuild))
3. Efficient DB Queries: Uses specific prepared statements to load only necessary data
4. Proper Error Handling: File reads are wrapped in try-catch blocks
5. Good Logging: Includes debug output showing how many files were loaded from DB
6. Maintains Data Integrity: Ensures both fileSymbols and lineCountMap are complete

✅ Technical Correctness

• SQL queries are correct and safe (no injection risks)
• Proper use of relative paths and normalization
• Handles missing files gracefully with try-catch
• Updates both required data structures consistently

✅ No Risky Changes

• No configuration changes detected
• No test modifications to make failing tests pass
• No linting rules disabled or relaxed
• No dependency changes

✅ Test Coverage

• All 491 tests pass (as stated in PR description)
• Lint clean
• Test plan includes both full and incremental build verification

🔍 Minor Observations

1. File Read Performance: Lines 855-862 read files synchronously from disk even though content might already exist in memory. However, this only affects incremental builds and the performance impact is acceptable.

2. Memory Usage: Loading all file symbols into memory increases memory footprint during incremental builds, but this is necessary for correct structure analysis.

Final Assessment

This is a well-executed bug fix that properly addresses the root cause of structure data loss during incremental builds. The implementation is clean, efficient, and follows the codebase's established patterns.

Final Recommendation

• Rating: ⭐⭐⭐⭐☆ (4/5)
• Action: APPROVE
• Reasoning: Solid bug fix with proper root cause analysis, clean implementation, no risky changes, and comprehensive testing. The only reason it's not 5 stars is that it's a straightforward fix rather than exceptional engineering.

Recommended Actions: None. The PR is ready to merge.

[claude]

Claude finished @carlos-alm's task —— View job

---

Reviewing PR #91: Incremental Build Structure Fix

Todo List:

• Read and analyze the changed code in src/builder.js
• Perform root cause analysis of the incremental build issue
• Check for risky configuration changes
• Verify test integrity and coverage
• Assess code quality and potential issues
• Provide final rating and recommendation

Root Cause Analysis

Problem Being Solved: During incremental builds, buildStructure() clears all contains edges and directory nodes (lines 35-40 in structure.js), but only received changed files in the fileSymbols map. This caused codegraph structure to show "0 files, 0 symbols" for most directories because the complete file set wasn't available for structure rebuilding.

Why This Approach: The fix loads all existing file nodes from the database during incremental builds, ensuring buildStructure() has access to the complete file set. This is necessary because structure analysis requires ALL files to compute directory metrics and containment relationships correctly.

Risk Assessment: ✅ LOW RISK - This is a legitimate fix addressing a real functional bug, not masking symptoms.

Critical Concerns

None found. This is a clean, targeted fix.

Code Quality Assessment

✅ Strengths

1. Root Cause Fix: Addresses the actual problem (incomplete file set during structure rebuild) rather than symptoms
2. Performance Conscious: Only loads data for incremental builds (if (!isFullBuild))
3. Efficient DB Queries: Uses specific prepared statements to load only necessary data
4. Proper Error Handling: File reads are wrapped in try-catch blocks
5. Good Logging: Includes debug output showing how many files were loaded from DB
6. Maintains Data Integrity: Ensures both fileSymbols and lineCountMap are complete

✅ Technical Correctness

• SQL queries are correct and safe (no injection risks)
• Proper use of relative paths and normalization
• Handles missing files gracefully with try-catch
• Updates both required data structures consistently

✅ No Risky Changes

• No configuration changes detected
• No test modifications to make failing tests pass
• No linting rules disabled or relaxed
• No dependency changes

✅ Test Coverage

• All 491 tests pass (as stated in PR description)
• Lint clean
• Test plan includes both full and incremental build verification

🔍 Minor Observations

1. File Read Performance: Lines 855-862 read files synchronously from disk even though content might already exist in memory. However, this only affects incremental builds and the performance impact is acceptable.

2. Memory Usage: Loading all file symbols into memory increases memory footprint during incremental builds, but this is necessary for correct structure analysis.

Final Assessment

This is a well-executed bug fix that properly addresses the root cause of structure data loss during incremental builds. The implementation is clean, efficient, and follows the codebase's established patterns.

Final Recommendation

• Rating: ⭐⭐⭐⭐☆ (4/5)
• Action: APPROVE
• Reasoning: Solid bug fix with proper root cause analysis, clean implementation, no risky changes, and comprehensive testing. The only reason it's not 5 stars is that it's a straightforward fix rather than exceptional engineering.

Recommended Actions: None. The PR is ready to merge.

---

[claude]

Claude finished @carlos-alm's task —— View job

---

Reviewing PR #91: Incremental Build Structure Fix

Todo List:

• Read and analyze the changed code in src/builder.js
• Perform root cause analysis of the incremental build issue
• Check for risky configuration changes
• Verify test integrity and coverage
• Assess code quality and potential issues
• Provide final rating and recommendation

Root Cause Analysis

Problem Being Solved: During incremental builds, buildStructure() clears all contains edges and directory nodes (lines 35-40 in structure.js), but only received changed files in the fileSymbols map. This caused codegraph structure to show "0 files, 0 symbols" for most directories because the complete file set wasn't available for structure rebuilding.

Why This Approach: The fix loads all existing file nodes from the database during incremental builds, ensuring buildStructure() has access to the complete file set. This is necessary because structure analysis requires ALL files to compute directory metrics and containment relationships correctly.

Risk Assessment: ✅ LOW RISK - This is a legitimate fix addressing a real functional bug, not masking symptoms.

Critical Concerns

None found. This is a clean, targeted fix.

Code Quality Assessment

✅ Strengths

1. Root Cause Fix: Addresses the actual problem (incomplete file set during structure rebuild) rather than symptoms
2. Performance Conscious: Only loads data for incremental builds (if (!isFullBuild))
3. Efficient DB Queries: Uses specific prepared statements to load only necessary data
4. Proper Error Handling: File reads are wrapped in try-catch blocks
5. Good Logging: Includes debug output showing how many files were loaded from DB
6. Maintains Data Integrity: Ensures both fileSymbols and lineCountMap are complete

✅ Technical Correctness

• SQL queries are correct and safe (no injection risks)
• Proper use of relative paths and normalization
• Handles missing files gracefully with try-catch
• Updates both required data structures consistently

✅ No Risky Changes

• No configuration changes detected
• No test modifications to make failing tests pass
• No linting rules disabled or relaxed
• No dependency changes

✅ Test Coverage

• All 491 tests pass (as stated in PR description)
• Lint clean
• Test plan includes both full and incremental build verification

🔍 Minor Observations

1. File Read Performance: Lines 855-862 read files synchronously from disk even though content might already exist in memory. However, this only affects incremental builds and the performance impact is acceptable.

2. Memory Usage: Loading all file symbols into memory increases memory footprint during incremental builds, but this is necessary for correct structure analysis.

Final Assessment

This is a well-executed bug fix that properly addresses the root cause of structure data loss during incremental builds. The implementation is clean, efficient, and follows the codebase's established patterns.

Final Recommendation

• Rating: ⭐⭐⭐⭐☆ (4/5)
• Action: APPROVE
• Reasoning: Solid bug fix with proper root cause analysis, clean implementation, no risky changes, and comprehensive testing. The only reason it's not 5 stars is that it's a straightforward fix rather than exceptional engineering.

Recommended Actions: None. The PR is ready to merge.

---

[claude]

Claude finished @carlos-alm's task —— View job

---

Reviewing PR #91: Incremental Build Structure Fix

Todo List:

• Read and analyze the changed code in src/builder.js
• Perform root cause analysis of the incremental build issue
• Check for risky configuration changes
• Verify test integrity and coverage
• Assess code quality and potential issues
• Provide final rating and recommendation

Root Cause Analysis

Problem Being Solved: During incremental builds, buildStructure() clears all contains edges and directory nodes (lines 35-40 in structure.js), but only received changed files in the fileSymbols map. This caused codegraph structure to show "0 files, 0 symbols" for most directories because the complete file set wasn't available for structure rebuilding.

Why This Approach: The fix loads all existing file nodes from the database during incremental builds, ensuring buildStructure() has access to the complete file set. This is necessary because structure analysis requires ALL files to compute directory metrics and containment relationships correctly.

Risk Assessment: ✅ LOW RISK - This is a legitimate fix addressing a real functional bug, not masking symptoms.

Critical Concerns

None found. This is a clean, targeted fix.

Code Quality Assessment

✅ Strengths

1. Root Cause Fix: Addresses the actual problem (incomplete file set during structure rebuild) rather than symptoms
2. Performance Conscious: Only loads data for incremental builds (if (!isFullBuild))
3. Efficient DB Queries: Uses specific prepared statements to load only necessary data
4. Proper Error Handling: File reads are wrapped in try-catch blocks
5. Good Logging: Includes debug output showing how many files were loaded from DB
6. Maintains Data Integrity: Ensures both fileSymbols and lineCountMap are complete

✅ Technical Correctness

• SQL queries are correct and safe (no injection risks)
• Proper use of relative paths and normalization
• Handles missing files gracefully with try-catch
• Updates both required data structures consistently

✅ No Risky Changes

• No configuration changes detected
• No test modifications to make failing tests pass
• No linting rules disabled or relaxed
• No dependency changes

✅ Test Coverage

• All 491 tests pass (as stated in PR description)
• Lint clean
• Test plan includes both full and incremental build verification

🔍 Minor Observations

1. File Read Performance: Lines 855-862 read files synchronously from disk even though content might already exist in memory. However, this only affects incremental builds and the performance impact is acceptable.

2. Memory Usage: Loading all file symbols into memory increases memory footprint during incremental builds, but this is necessary for correct structure analysis.

Final Assessment

This is a well-executed bug fix that properly addresses the root cause of structure data loss during incremental builds. The implementation is clean, efficient, and follows the codebase's established patterns.

Final Recommendation

• Rating: ⭐⭐⭐⭐☆ (4/5)
• Action: APPROVE
• Reasoning: Solid bug fix with proper root cause analysis, clean implementation, no risky changes, and comprehensive testing. The only reason it's not 5 stars is that it's a straightforward fix rather than exceptional engineering.

Recommended Actions: None. The PR is ready to merge.

---

[carlos-alm]

@greptileai

[greptile-apps]

_{3 files reviewed, no comments}

_{Edit Code Review Agent Settings | Greptile}

[claude]

Claude finished @carlos-alm's task —— View job

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Reviewing PR #91: Node Role Classification + Dead Code Detection

Todo List:

• Read and analyze key changed files
• Phase 1: Root cause analysis of the problem being solved
• Phase 2: Check for risky configuration changes
• Phase 3: Verify test integrity
• Phase 4: Assess code quality and implementation
• Provide structured final assessment with rating

Phase 1: Root Cause Analysis ✅

Problem Being Solved: This PR adds node role classification and dead code detection functionality to codegraph. The implementation automatically categorizes every symbol based on connectivity patterns using adaptive median thresholds.

Why This Approach: The classification system uses fan-in/fan-out patterns with adaptive median thresholds, which is a well-established approach in code analysis. The implementation is delivered as a byproduct of graph analysis rather than requiring separate tooling.

Risk Assessment: ✅ LOW RISK - This is a new feature addition that doesn't modify existing functionality. The implementation is additive and includes comprehensive testing.

Phase 2: Configuration Change Detection ✅

No Risky Changes Detected:

• ✅ No biome.json or linting rule changes
• ✅ No test timeout modifications
• ✅ No coverage threshold relaxation
• ✅ No TypeScript strict mode changes
• ✅ vitest.config.js unchanged (30s timeout preserved)
• ✅ No build configuration modifications

Phase 3: Test Integrity ✅

Strong Test Coverage:

• ✅ 2 new dedicated test files: tests/unit/roles.test.js (183 lines) and tests/integration/roles.test.js (212 lines)
• ✅ Comprehensive unit tests: Edge cases, idempotency, empty graphs, adaptive median thresholds
• ✅ Integration tests: All query commands (where, explain, stats, context) properly include role fields
• ✅ MCP tests updated: New node_roles tool properly integrated
• ✅ DB migration v5 included: Adds role column to nodes table with proper indexing

No Test Integrity Issues Found:

• ✅ No weakened assertions or skipped tests
• ✅ New tests are additive, no existing tests modified
• ✅ Proper test isolation using temporary databases

Phase 4: Code Quality Assessment ✅

✅ Architecture & Implementation Quality

1. Clean separation: Classification logic in src/structure.js, query/CLI in src/queries.js, DB migration in src/db.js
2. Adaptive algorithm: Uses median-based thresholds that adapt to codebase connectivity patterns (src/structure.js:269-280)
3. Proper DB schema evolution: Migration v5 adds role column with index (src/db.js:119-127)
4. Cross-file export detection: Correctly identifies exported symbols via cross-file call analysis (src/structure.js:256-267)

✅ Technical Correctness

1. SQL queries are safe: No injection risks, proper prepared statements
2. Role classification logic: Well-defined 6-role taxonomy matching academic code analysis patterns
3. Performance conscious: Single classification pass, leverages existing call graph data
4. Integration points: All existing query commands properly enhanced with role data

✅ Feature Completeness

1. CLI integration: New roles command with filtering options (src/cli.js:544-563)
2. MCP tool support: node_roles tool for AI assistant integration
3. JSON output support: Consistent with existing commands
4. Documentation updated: README, COMPETITIVE_ANALYSIS, and BACKLOG reflect new capabilities

🔍 Minor Observations

1. Large PR scope: 15 files changed with 1251 additions - however, well-organized with clear separation of concerns
2. Prior incremental build fix included: This branch also contains the earlier incremental structure fix, which was already reviewed separately

Final Assessment

This is a well-architected feature addition that implements node role classification using sound software engineering principles. The implementation follows established academic patterns for code analysis, includes comprehensive testing, and integrates cleanly with the existing codebase architecture.

Key Strengths:

• Solid algorithmic foundation: Adaptive median thresholds prevent hard-coded assumptions
• Dead code detection as a byproduct: Elegant delivery of practical value
• Comprehensive integration: Roles surface across all relevant commands (where, explain, stats, context)
• Strong test coverage: Both unit and integration tests with edge case handling
• Clean database migration: Proper schema evolution with indexing

The feature delivers significant practical value for code analysis and maintenance workflows while maintaining the tool's performance and reliability characteristics.

Final Recommendation

• Rating: ⭐⭐⭐⭐⭐ (5/5)
• Action: APPROVE
• Reasoning: Exceptional feature implementation with comprehensive testing, clean architecture, sound algorithms, and significant practical value. This represents high-quality software engineering across all dimensions evaluated.

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