# Event Trace

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- **Type:** Skill
- **Install:** `agentstack add skill-hoangsonww-claude-code-agent-monitor-event-trace`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [hoangsonww](https://agentstack.voostack.com/s/hoangsonww)
- **Installs:** 0
- **Category:** [Databases](https://agentstack.voostack.com/c/databases)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [hoangsonww](https://github.com/hoangsonww)
- **Source:** https://github.com/hoangsonww/Claude-Code-Agent-Monitor/tree/master/plugins/ccam-devtools/skills/event-trace
- **Website:** https://hoangsonww.github.io/Claude-Code-Agent-Monitor/

## Install

```sh
agentstack add skill-hoangsonww-claude-code-agent-monitor-event-trace
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Event Trace

Build a chronological, annotated event timeline for a single session.

## Input

The user provides: **$ARGUMENTS**

This is a session ID. It may also be:
- `latest` / `last` — trace the most recently updated session
- `errors` — trace the most recent session whose status is `error`

## Data Sources

| Endpoint | Returns |
|----------|---------|
| `GET /api/sessions?limit=N` | session list (used to resolve `latest`/`errors` and the target id) |
| `GET /api/sessions/:id` | full session detail (status, model, cwd, started_at, ended_at, cost, nested agents + events) |
| `GET /api/events?session_id=X` | the ordered event stream: event_type, tool_name, summary, data, timestamp |

## Report Sections

### 1. Resolve the session
If `$ARGUMENTS` is a raw id, use it. If `latest`/`last`, call
`GET /api/sessions?limit=1`. If `errors`, call
`GET /api/sessions?limit=10&status=error` and pick the newest. Confirm the id
resolves via `GET /api/sessions/:id`; if not, report it as missing and stop.

### 2. Session header
From `GET /api/sessions/:id`: id, status, model, cwd, started_at → ended_at,
total duration, cost (USD to 4 decimals), and counts (events, agents).

### 3. Ordered timeline
From `GET /api/events?session_id=X`, list every event in timestamp order. One row
per event:

`| # | time | Δ since prev | event_type | tool_name | summary |`

Cover all event types present: SessionStart, PreToolUse, PostToolUse, Stop,
SubagentStop, Compaction, APIError, TurnDuration, Notification, SessionEnd.

### 4. Gap & failure highlights
Annotate the timeline:
- **Gaps**: any Δ > 30s between consecutive events — mark ⏳ and note the wait.
- **Unpaired tool calls**: a PreToolUse with no matching PostToolUse (same
  tool_name, next in stream) — mark ⚠️ "no completion recorded".
- **Failures**: APIError events and PostToolUse whose `summary`/`data` indicates
  an error — mark ❌ with the error text.
- **Compaction**: mark ♻️ and note it resets the visible token baseline.
- **Missing bookends**: no SessionStart at the head or no Stop/SessionEnd at the
  tail of an ended session — mark 🚩.

### 5. Verdict
One line: CLEAN, GAPS DETECTED, or FAILURES PRESENT — with the count of each
flag type and the single most likely thing to investigate next.

## Output

- Markdown timeline table, events in strict timestamp order.
- Status glyphs inline: ✅ ok, ❌ error, ⚠️ warning/unpaired, ⏳ gap, ♻️ compaction, 🚩 missing bookend.
- Currency in USD to 4 decimals.
- Cite only event data returned by the API — do not invent timestamps or summaries.
- If the dashboard is unreachable, tell the user to start it with `npm start` from the repo root.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [hoangsonww](https://github.com/hoangsonww)
- **Source:** [hoangsonww/Claude-Code-Agent-Monitor](https://github.com/hoangsonww/Claude-Code-Agent-Monitor)
- **License:** MIT
- **Homepage:** https://hoangsonww.github.io/Claude-Code-Agent-Monitor/

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-hoangsonww-claude-code-agent-monitor-event-trace
- Seller: https://agentstack.voostack.com/s/hoangsonww
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.