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Systematically investigate and fix bugs using token-efficient context gathering. Reproduces the issue first, localizes with blame and history, traces the call path, then verifies the fix. Use when asked to fix a bug, investigate an error, or debug unexpected behavior.
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SOC 職業分類に基づく
| name | debug-bug |
| description | Systematically investigate and fix bugs using token-efficient context gathering. Reproduces the issue first, localizes with blame and history, traces the call path, then verifies the fix. Use when asked to fix a bug, investigate an error, or debug unexpected behavior. |
| compatibility | Requires tokenlean CLI tools (npm i -g tokenlean) and git |
Systematically find and fix bugs while reading as little code as possible.
Reproduce → Localize → Trace → Fix → Verify
tl-run "<repro command>" # Capture the actual error output
No fix without reproduction. If no repro command is given, ask for one. If the bug is in tests, run the failing test. This step is non-negotiable.
Narrow down where the bug lives:
tl-errors # Scan for error patterns in the codebase
tl-blame <file> # Recent changes to the file mentioned in the error
tl-history <file> # If this is a regression — what changed recently?
If the error includes a stack trace, start with the top frame. If it's vague, use tl-search "<error message>" to find where the error originates.
Understand the code path without reading entire files:
tl-flow <function> <file> # Call graph around the failing function
tl-deps <file> # What the buggy file depends on
tl-snippet <function> <file> # Read only the relevant function
Apply the minimal fix. Then check for side effects:
tl-guard # Circular deps, unused exports, secrets
tl-impact <file> # Will the fix affect dependents?
tl-run "<repro command>" # Confirm the bug is fixed
tl-run "<test command>" # Ensure no regressions
Bug report → Can you reproduce it?
├─ Yes → What layer does the error come from?
│ ├─ Stack trace points to a file → tl-blame + tl-snippet on that file
│ ├─ Error is vague / no stack → tl-errors + tl-search for the error message
│ └─ Happening in dependency → tl-deps to confirm, check dep version
├─ No → Ask for reproduction steps before proceeding
└─ Intermittent → tl-history on suspect files, look for recent changes
tl-search "<error message>" to find where errors are throwntl-diff for recent regressions — the bug may be in the last few commitsAdd new functionality by understanding existing patterns and dependencies before writing code. Locates where the feature belongs, studies conventions, implements following precedent, then verifies integration. Use when asked to add a feature, flag, endpoint, component, or module.
Thorough code review using token-efficient context gathering. Analyzes PRs, diffs, or staged changes by checking blast radius, complexity, and dependencies before reviewing the actual code. Use when asked to review a PR, review changes, or do a code review.
Diagnose and fix performance issues by measuring before optimizing. Establishes baselines, identifies bottlenecks through call graphs and complexity analysis, then confirms improvements with numbers. Use when asked to optimize, speed up, reduce memory usage, or fix slowness.
Efficiently explore and understand an unfamiliar codebase using token-lean context gathering. Maps project structure, identifies key files, and builds understanding progressively without reading everything. Use when onboarding to a new project, asked to understand a codebase, or starting work in unfamiliar code.
Migrate frameworks, APIs, or language versions incrementally with verification at each step. Surveys the migration surface, batches work by dependency order, and commits after each verified batch. Use when asked to migrate between frameworks, upgrade major versions, or adapt to new API versions.
Refactor code safely by analyzing blast radius and dependencies before making changes. Covers renaming, moving, extracting, and restructuring code with verification at each step. Use when refactoring, renaming symbols, extracting functions, moving files, or restructuring code.