Free SKILL.md scraped from GitHub. Clone the repo or copy the file directly into your Claude Code skills directory.
npx versuz@latest install hoangsonww-claude-code-agent-monitor-plugins-ccam-devtools-skills-session-debuggit clone https://github.com/hoangsonww/Claude-Code-Agent-Monitor.gitcp Claude-Code-Agent-Monitor/SKILL.MD ~/.claude/skills/hoangsonww-claude-code-agent-monitor-plugins-ccam-devtools-skills-session-debug/SKILL.md---
description: >
Debug a specific session by inspecting its full event chain (PreToolUse,
PostToolUse, Stop, SubagentStop, Compaction, APIError, TurnDuration,
Notification events), agent hierarchy (recursive parent/child tree with
subagent_type and depth), token usage with compaction baselines, workflow
intelligence data (orchestration DAG, error propagation by depth), and
session metadata (thinking_blocks, turn_count, total_turn_duration_ms).
---
# Session Debug
Debug and inspect a Claude Code session from Agent Monitor data.
## Input
The user provides: **$ARGUMENTS**
This may be:
- A session ID to debug
- "latest" or "last" for the most recent session
- "errors" to find and debug the most recent errored session
## Procedure
1. **Identify the target session**:
- If session ID given: `GET /api/sessions/{id}` from `http://localhost:4820`
- If "latest": `GET /api/sessions?limit=1` (default sort: most recently updated first)
- If "errors": `GET /api/sessions?limit=10&status=error`
2. **Collect full session data**:
- Session metadata: status, model, cwd, timestamps, duration
- Events: `GET /api/events?session_id={session_id}` — full event timeline
- Agents: `GET /api/agents?session_id={session_id}` — all agents in session
- Cost: `GET /api/pricing/cost/{session_id}`
3. **Analyze the session**:
### Session Lifecycle
- Start time → first event → last event → end time
- Status transitions (active → working → completed/error)
- Total duration and active-vs-idle time
### Event Chain Analysis
- Chronological event list with timestamps and durations
- Identify the **critical path** (longest chain of dependent events)
- Flag events that took unusually long
- Highlight error events with full error context
### Agent Inspection
- List all agents: type, task, status, duration
- Subagent tree visualization (parent → children)
- Agents that failed and their last known state
- Agent switching patterns (when and why new agents spawned)
### Tool Execution Trace
- Every tool invocation in order with: tool name, duration, success/failure
- Failed tool calls with error messages
- Tool retry patterns (same tool called multiple times)
### Anomaly Detection
- Events out of expected order
- Gaps in event timeline (>30s with no events)
- Duplicate events or agent states
- Token usage spikes (compaction indicators)
4. **Diagnosis**:
- Root cause hypothesis (if errors present)
- Contributing factors
- Remediation suggestions
## Output Format
Present as a debug report with:
- Session summary header (ID, status, model, duration, cost)
- Color-coded timeline (✅ success, ❌ error, ⚠️ warning, ℹ️ info)
- Agent tree diagram
- Diagnosis section with numbered findings