Claude-skill-registry debugger-detective
⚡ PRIMARY TOOL for: 'why is X broken', 'find bug source', 'root cause analysis', 'trace error', 'debug issue', 'find where X fails'. Uses claudemem v0.3.0 AST with context command for call chain analysis. GREP/FIND/GLOB ARE FORBIDDEN.
git clone https://github.com/majiayu000/claude-skill-registry
T=$(mktemp -d) && git clone --depth=1 https://github.com/majiayu000/claude-skill-registry "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/data/debugger-detective" ~/.claude/skills/majiayu000-claude-skill-registry-debugger-detective && rm -rf "$T"
skills/data/debugger-detective/SKILL.md⛔⛔⛔ CRITICAL: AST STRUCTURAL ANALYSIS ONLY ⛔⛔⛔
╔══════════════════════════════════════════════════════════════════════════════╗ ║ ║ ║ 🧠 THIS SKILL USES claudemem v0.3.0 AST ANALYSIS EXCLUSIVELY ║ ║ ║ ║ ❌ GREP IS FORBIDDEN ║ ║ ❌ FIND IS FORBIDDEN ║ ║ ❌ GLOB IS FORBIDDEN ║ ║ ║ ║ ✅ claudemem --nologo context <name> --raw FOR FULL CALL CHAIN ║ ║ ✅ claudemem --nologo callers <name> --raw TO TRACE BACK TO SOURCE ║ ║ ✅ claudemem --nologo callees <name> --raw TO TRACE FORWARD ║ ║ ║ ║ ⭐ v0.3.0: context shows full call chain for root cause analysis ║ ║ ║ ╚══════════════════════════════════════════════════════════════════════════════╝
Debugger Detective Skill
Version: 3.3.0 Role: Debugger / Incident Responder Purpose: Bug investigation and root cause analysis using AST call chain tracing with blast radius impact analysis
Role Context
You are investigating this codebase as a Debugger. Your focus is on:
- Error origins - Where exceptions are thrown
- Call chains - How execution flows to the failure point
- State mutations - What changed the data before failure
- Root causes - The actual source of problems (not just symptoms)
- Impact radius - What else might be affected
Why context
is Perfect for Debugging
contextThe
context command shows you:
- Symbol definition = Where the buggy code is
- Callers = How we got here (trace backwards)
- Callees = What happens next (trace forward)
- Full call chain = Complete picture for root cause analysis
Debugger-Focused Commands (v0.3.0)
Find the Bug Location
# Find the function mentioned in error claudemem --nologo symbol authenticate --raw # Get full context (callers + callees) claudemem --nologo context authenticate --raw
Trace Back to Source (callers)
# Who called this function? (trace backwards) claudemem --nologo callers authenticate --raw # Follow the chain backwards claudemem --nologo callers LoginController --raw claudemem --nologo callers handleRequest --raw
Trace Forward to Effect (callees)
# What does this function call? (trace forward) claudemem --nologo callees authenticate --raw # Find where state changes happen claudemem --nologo callees updateSession --raw
Blast Radius Analysis (v0.4.0+ Required)
# After finding the bug, check what else is affected IMPACT=$(claudemem --nologo impact buggyFunction --raw) if [ -z "$IMPACT" ] || echo "$IMPACT" | grep -q "No callers"; then echo "No static callers - bug is isolated (or dynamically called)" else echo "$IMPACT" echo "" echo "This shows:" echo "- Direct callers (immediately affected)" echo "- Transitive callers (potentially affected)" echo "- Complete list for testing after fix" fi
Use for:
- Post-fix verification (test all impacted code)
- Regression prevention (know what to test)
- Incident documentation (impact scope)
Limitations: Event-driven/callback architectures may have callers not visible to static analysis.
Error Origin Hunting
# Map error handling code claudemem --nologo map "throw error exception" --raw # Find specific error types claudemem --nologo symbol AuthenticationError --raw # Who throws this error? claudemem --nologo callers AuthenticationError --raw
State Mutation Tracking
# Find where state changes claudemem --nologo map "set state update mutate" --raw # Find the mutation function claudemem --nologo symbol updateUserState --raw # Who calls this mutation? claudemem --nologo callers updateUserState --raw
PHASE 0: MANDATORY SETUP
Step 1: Verify claudemem v0.3.0
which claudemem && claudemem --version # Must be 0.3.0+
Step 2: If Not Installed → STOP
Use AskUserQuestion (see ultrathink-detective for template)
Step 3: Check Index Status
# Check claudemem installation and index claudemem --version && ls -la .claudemem/index.db 2>/dev/null
Step 3.5: Check Index Freshness
Before proceeding with investigation, verify the index is current:
# First check if index exists if [ ! -d ".claudemem" ] || [ ! -f ".claudemem/index.db" ]; then # Use AskUserQuestion to prompt for index creation # Options: [1] Create index now (Recommended), [2] Cancel investigation exit 1 fi # Count files modified since last index STALE_COUNT=$(find . -type f \( -name "*.ts" -o -name "*.tsx" -o -name "*.js" -o -name "*.jsx" -o -name "*.py" -o -name "*.go" -o -name "*.rs" \) \ -newer .claudemem/index.db 2>/dev/null | grep -v "node_modules" | grep -v ".git" | grep -v "dist" | grep -v "build" | wc -l) STALE_COUNT=$((STALE_COUNT + 0)) # Normalize to integer if [ "$STALE_COUNT" -gt 0 ]; then # Get index time with explicit platform detection if [[ "$OSTYPE" == "darwin"* ]]; then INDEX_TIME=$(stat -f "%Sm" -t "%Y-%m-%d %H:%M" .claudemem/index.db 2>/dev/null) else INDEX_TIME=$(stat -c "%y" .claudemem/index.db 2>/dev/null | cut -d'.' -f1) fi INDEX_TIME=${INDEX_TIME:-"unknown time"} # Get sample of stale files STALE_SAMPLE=$(find . -type f \( -name "*.ts" -o -name "*.tsx" \) \ -newer .claudemem/index.db 2>/dev/null | grep -v "node_modules" | grep -v ".git" | head -5) # Use AskUserQuestion (see template in ultrathink-detective) fi
Step 4: Index if Needed
claudemem index
Workflow: Bug Investigation (v0.3.0)
Phase 1: Locate the Symptom
# Find where the error appears claudemem --nologo map "error message keywords" --raw # Or find the specific function claudemem --nologo symbol failingFunction --raw
Phase 2: Get Full Context
# Get callers + callees in one command claudemem --nologo context failingFunction --raw
Phase 3: Trace Backwards (Find Root Cause)
# For each caller, check if it's the source claudemem --nologo callers caller1 --raw claudemem --nologo callers caller2 --raw # Keep tracing until you find the root
Phase 4: Verify the Chain
# Once you suspect a root cause, verify the path claudemem --nologo callees suspectedRoot --raw # Does it lead to the symptom?
Phase 5: Check Impact
# What else calls the buggy code? claudemem --nologo callers buggyFunction --raw # These are all potentially affected
Output Format: Bug Investigation Report
1. Symptom Summary
┌─────────────────────────────────────────────────────────┐ │ BUG INVESTIGATION │ ├─────────────────────────────────────────────────────────┤ │ Symptom: User sees "undefined" in profile name │ │ Location: src/components/Profile.tsx:45 │ │ Error Type: Data inconsistency / Null reference │ │ Search Method: claudemem v0.3.0 (AST call chain) │ └─────────────────────────────────────────────────────────┘
2. Call Chain Trace
❌ SYMPTOM: undefined rendered └── src/components/Profile.tsx:45 └── user.name is undefined ↑ CALLER CHAIN (trace backwards): └── useUser hook (src/hooks/useUser.ts:23) ↑ └── fetchUser API (src/api/user.ts:67) ↑ └── userMapper (src/mappers/user.ts:12) ↑ 🔍 ROOT CAUSE FOUND HERE
3. Root Cause Analysis
🔍 ROOT CAUSE IDENTIFIED: Location: src/mappers/user.ts:12 Problem: Field name mismatch API Response: { fullName: "John Doe" } Mapper Expects: { full_name: "..." } Result: name = undefined Evidence: - callees of fetchUser → userMapper - callers of userMapper → useUser → Profile - Complete chain verified via context command
4. Impact Analysis
⚠️ OTHER AFFECTED CODE: claudemem --nologo callers userMapper --raw shows: - useUser hook (main app) - useAdmin hook (admin panel) - tests/user.test.ts All 3 locations may have the same bug!
Scenarios
Scenario: Null Pointer Exception
# Step 1: Find where undefined is used claudemem --nologo map "undefined null" --raw # Step 2: Get context of the failing function claudemem --nologo context renderProfile --raw # Step 3: Trace backwards through callers claudemem --nologo callers getUserData --raw # Step 4: Find where null was introduced claudemem --nologo callees fetchUser --raw
Scenario: Race Condition
# Step 1: Find async operations claudemem --nologo map "async await promise" --raw # Step 2: Find shared state claudemem --nologo symbol sharedState --raw # Step 3: Who reads it? claudemem --nologo callers sharedState --raw # Step 4: Who writes it? claudemem --nologo callees updateState --raw
Scenario: Incorrect Behavior
# Step 1: Find the function with wrong behavior claudemem --nologo symbol calculateTotal --raw # Step 2: What does it depend on? claudemem --nologo callees calculateTotal --raw # Step 3: Who provides input? claudemem --nologo callers calculateTotal --raw
Result Validation Pattern
After EVERY claudemem command, validate results:
Context Validation for Debugging
When tracing call chains:
CONTEXT=$(claudemem --nologo context failingFunction --raw) EXIT_CODE=$? # Check for failure if [ "$EXIT_CODE" -ne 0 ]; then DIAGNOSIS=$(claudemem status 2>&1) # Use AskUserQuestion fi # Validate all sections present if ! echo "$CONTEXT" | grep -q "\[symbol\]"; then # Missing symbol section - function not found # Use AskUserQuestion: Reindex, Different name, or Cancel fi if ! echo "$CONTEXT" | grep -q "\[callers\]"; then # Missing callers - may be entry point or index issue # Entry points (API handlers, main) have 0 callers - this is expected fi if ! echo "$CONTEXT" | grep -q "\[callees\]"; then # Missing callees - may be leaf function or index issue # Leaf functions (console.log, throw) have 0 callees - this is expected fi
Empty Results Handling
CALLERS=$(claudemem --nologo callers suspectedBug --raw) # 0 callers could mean: # 1. Entry point (main, API handler) - expected # 2. Dead code - use dead-code command (v0.4.0+) # 3. Dynamically called - check for import(), eval, reflection if echo "$CALLERS" | grep -qi "error\|not found"; then # Actual error vs no callers # Use AskUserQuestion fi
FALLBACK PROTOCOL
CRITICAL: Never use grep/find/Glob without explicit user approval.
If claudemem fails or returns irrelevant results:
- STOP - Do not silently switch tools
- DIAGNOSE - Run
claudemem status - REPORT - Tell user what happened
- ASK - Use AskUserQuestion for next steps
// Fallback options (in order of preference) AskUserQuestion({ questions: [{ question: "claudemem bug investigation failed or found no call chain. How should I proceed?", header: "Debugging Issue", multiSelect: false, options: [ { label: "Reindex codebase", description: "Run claudemem index (~1-2 min)" }, { label: "Try different function name", description: "Search for related functions" }, { label: "Use grep (not recommended)", description: "Traditional search - loses call chain tracing" }, { label: "Cancel", description: "Stop investigation" } ] }] })
See ultrathink-detective skill for complete Fallback Protocol documentation.
Anti-Patterns
| Anti-Pattern | Why Wrong | Correct Approach |
|---|---|---|
| No call relationships | |
| Read random files | No direction | Trace callers/callees systematically |
| Fix symptom only | Bug returns | Trace to root cause with |
| Skip impact check | Miss related bugs | ALWAYS check all |
Debugging Tips
- Start at symptom - Use
to find where error appearssymbol - Get full context - Use
for callers + callees togethercontext - Trace backwards - Follow
chain to root causecallers - Verify forward - Use
to confirm the pathcallees - Check impact - All
of buggy code may be affectedcallers
Notes
is your primary tool - Shows full call chaincontext- Trace backwards with
- Find root cause, not just symptomcallers - Verify with
- Confirm the execution pathcallees - Check all callers after fixing - Don't leave other bugs
- Works best with TypeScript, Go, Python, Rust codebases
Maintained by: MadAppGang Plugin: code-analysis v2.7.0 Last Updated: December 2025 (v3.3.0 - Cross-platform compatibility, inline templates, improved validation)