dead-code-removal
Dead Code Removal
Dead code removal via massively parallel scanning and execution. You are the ORCHESTRATOR — you scan, verify, batch, then execute all removals with atomic commits.
Rules:
- Reference verification is law. Verify with grep/language tools before ANY removal decision.
- Never remove entry points. Main entry files, test files, config files — off-limits.
False-positive guards — NEVER mark as dead:
- Symbols in entry point files or barrel
indexre-exports - Symbols referenced in test files (tests are valid consumers)
- Symbols with
@public/@apidoc tags - Hook factories (
createXXXHook), tool factories (createXXXTool), plugin definitions - Command templates, skill definitions, config objects
- Symbols in package exports
PHASE 1: SCAN — Find Dead Code Candidates
Run ALL of these in parallel:
Compiler/linter strict mode (primary scanner — run FIRST):
# TypeScript
npx tsc --noEmit --noUnusedLocals --noUnusedParameters 2>&1
# Python
vulture src/ --min-confidence 80
# Go
staticcheck -checks U1000 ./...
This gives you the definitive list of unused locals, imports, parameters, and types with exact file:line locations.
Orphaned file detection (run simultaneously): Find files in src/ NOT imported by any other file. Check all import statements. EXCLUDE: index files, test files, entry points, markdown, config files. Return: file paths.
Unused export detection (run simultaneously): Find exported functions/types/constants that are never imported by other files. Cross-reference: for each export, grep the symbol name across src/ — if it only appears in its own file, it's a candidate. EXCLUDE: entry point exports, test files. Return: file path, line, symbol name, export type.
Collect all results into a master candidate list.
PHASE 2: VERIFY — Reference Confirmation (Zero False Positives)
For EACH candidate from Phase 1:
# Search for all references (excluding the declaration itself)
grep -rn "symbolName" src/ --include="*.ts" | grep -v "declaration_file.ts"
# Or use language-specific tools:
# TypeScript: ts-prune, ts-unused-exports
# Python: vulture --min-confidence 80
# Go: staticcheck -checks U1000
# 0 references = CONFIRMED dead
# 1+ references = NOT dead, drop from list
Also apply the false-positive guards above. Produce a confirmed list:
| # | File | Symbol | Type | Action |
|---|------|--------|------|--------|
| 1 | src/foo.ts:42 | unusedFunc | function | REMOVE |
| 2 | src/bar.ts:10 | OldType | type | REMOVE |
| 3 | src/baz.ts:7 | ctx | parameter | PREFIX _ |
Action types:
REMOVE— delete the symbol/import/file entirelyPREFIX _— unused function parameter required by signature → rename to_paramName
If ZERO confirmed: report "No dead code found" and STOP.
PHASE 3: BATCH — Group by File for Conflict-Free Parallelism
Goal: maximize parallel execution with ZERO conflicts.
- Group confirmed dead code items by FILE PATH
- All items in the SAME file go to the SAME batch (prevents two agents editing the same file)
- If a dead FILE (entire file deletion) exists, it's its own batch
- Target 5-15 batches. If fewer than 5 items total, use 1 batch per item.
Example batching:
Batch A: [src/hooks/foo/hook.ts — 3 unused imports]
Batch B: [src/features/bar/manager.ts — 2 unused constants, 1 dead function]
Batch C: [src/tools/baz/tool.ts — 1 unused param, src/tools/baz/types.ts — 1 unused type]
Batch D: [src/dead-file.ts — entire file deletion]
Files in the same directory CAN be batched together (they won't conflict as long as no two agents edit the same file). Maximize batch count for parallelism.
PHASE 4: EXECUTE — Apply Removals
For EACH batch:
Protocol
- Read each file to understand exact syntax at the target lines
- Re-verify with grep that the symbol is still dead (another batch may have changed things)
- Apply the change:
- Unused import (only symbol in line): remove entire import line
- Unused import (one of many): remove only that symbol from the import list
- Unused constant/function/type: remove the declaration. Clean up trailing blank lines.
- Unused parameter: prefix with
_(do NOT remove — required by signature) - Dead file: delete with
rm
- After ALL edits in this batch, run the type checker / build
- If build fails:
git checkout -- [files]and report failure - If build passes: stage ONLY your files and commit:
git add [your-specific-files] && git commit -m "refactor: remove dead code from [brief file list]" - Report what you removed and the commit hash
Critical Rules
- Stage ONLY your batch's files (
git add [specific files]). NEVERgit add -A— other batches may be running in parallel. - If build fails after your edits, REVERT all changes and report. Do not attempt to fix.
- Pre-existing test failures in other files are expected. Only the type checker / build matters for your batch.
PHASE 5: FINAL VERIFICATION
After ALL batches complete:
# Language-specific type check (must pass)
npx tsc --noEmit # TypeScript
mypy src/ # Python
go vet ./... # Go
# Tests (note any NEW failures vs pre-existing)
npm test
pytest
# Build (must pass)
npm run build
Produce summary:
## Dead Code Removal Complete
### Removed
| # | Symbol | File | Type | Commit |
|---|--------|------|------|--------|
| 1 | unusedFunc | src/foo.ts | function | abc1234 |
### Skipped (verification failed)
| # | Symbol | File | Reason |
|---|--------|------|--------|
### Verification
- Type check: PASS/FAIL
- Tests: X passing, Y failing (Z pre-existing)
- Build: PASS/FAIL
- Total removed: N symbols across M files
- Total commits: K atomic commits
SCOPE CONTROL
If a specific scope is provided, narrow the scan:
- File path → only that file
- Directory → only that directory
- Symbol name → only that symbol
allor empty → full project scan (default)
ABORT CONDITIONS
STOP and report if:
- More than 50 candidates found (ask user to narrow scope or confirm proceeding)
- Build breaks and cannot be fixed by reverting
Inspired by: oh-my-opencode remove-deadcode command