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Agent Orchestration
Skill

/massgen-log-analyzer

Run MassGen experiments and analyze logs using automation mode, logfire tracing, and SQL queries. Use this skill for performance analysis, debugging agent behavior, evaluating coordination patterns, and improving the logging structure, or whenever an ANALYSIS_REPORT.md is needed

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massgen
1.1k19 skills
Install
$ npx -y skills add massgen/massgen --skill massgen-log-analyzer --agent claude-code

How it fires

How this skill gets triggered: by you, by Claude, or both.

  • Fires itselfAuto-invocation. Claude auto-loads it when your prompt matches the work.Auto-invocation is when the right skill fires by itself at the right moment, driven by a FLOW.md router and a hook, instead of you invoking it by name. It is the difference between a skill being installed and a skill actually getting used.Read the full definition →
  • You can call itInvoke it directly when you want it.
  • Slash command/massgen-log-analyzer

Context preview

The summary Claude sees to decide when to auto-load this skill.

Run MassGen experiments and analyze logs using automation mode, logfire tracing, and SQL queries. Use this skill for performance analysis, debugging agent behavior, evaluating coordination patterns, and improving the logging structure, or whenever an ANALYSIS_REPORT.md is needed

SKILL.md

massgen-log-analyzer.SKILL.md
name: massgen-log-analyzer
description: Run MassGen experiments and analyze logs using automation mode, logfire tracing, and SQL queries. Use this skill for performance analysis, debugging agent behavior, evaluating coordination patterns, and improving the logging structure, or whenever an ANALYSIS_REPORT.md is needed in a log directory.

MassGen Log Analyzer

This skill provides a structured workflow for running MassGen experiments and analyzing the resulting traces and logs using Logfire.

Purpose

The log-analyzer skill helps you:

  • Run MassGen experiments with proper instrumentation
  • Query and analyze traces hierarchically
  • Debug agent behavior and coordination patterns
  • Measure performance and identify bottlenecks
  • Improve the logging structure itself
  • **Generate markdown analysis reports** saved to the log directory

CLI Quick Reference

The `massgen logs` CLI provides quick access to log analysis:

List Logs with Analysis Status

uv run massgen logs list                    # Show all recent logs with analysis status
uv run massgen logs list --analyzed         # Only logs with ANALYSIS_REPORT.md
uv run massgen logs list --unanalyzed       # Only logs needing analysis
uv run massgen logs list --limit 20         # Show more logs

Generate Analysis Prompt

# Run from within your coding CLI (e.g., Claude Code) so it sees output
uv run massgen logs analyze                 # Analyze latest turn of latest log
uv run massgen logs analyze --log-dir PATH  # Analyze specific log
uv run massgen logs analyze --turn 1        # Analyze specific turn

The prompt output tells your coding CLI to use this skill on the specified log directory.

Multi-Agent Self-Analysis

uv run massgen logs analyze --mode self                 # Run 3-agent analysis team (prompts if report exists)
uv run massgen logs analyze --mode self --force         # Overwrite existing report without prompting
uv run massgen logs analyze --mode self --turn 2        # Analyze specific turn
uv run massgen logs analyze --mode self --config PATH   # Use custom config

Self-analysis mode runs MassGen with multiple agents to analyze logs from different perspectives (correctness, efficiency, behavior) and produces a combined ANALYSIS_REPORT.md.

Multi-Turn Sessions

MassGen log directories support multiple turns (coordination sessions). Each turn has its own `turn_N/` directory with attempts inside:

log_YYYYMMDD_HHMMSS/
├── turn_1/                    # First coordination session
│   ├── ANALYSIS_REPORT.md     # Report for turn 1
│   ├── attempt_1/             # First attempt
│   └── attempt_2/             # Retry if orchestration restarted
├── turn_2/                    # Second coordination session (if multi-turn)
│   ├── ANALYSIS_REPORT.md     # Report for turn 2
│   └── attempt_1/

When analyzing, the `--turn` flag specifies which turn to analyze. Without it, the latest turn is analyzed.

When to Use Logfire vs Local Logs

**Use Local Log Files When:**

  • Analyzing command patterns and repetition (commands are in `streaming_debug.log`)
  • Checking detailed tool arguments and outputs (in `coordination_events.json`)
  • Reading vote reasoning and agent decisions (in `agent_*/*/vote.json`)
  • Viewing the coordination flow table (in `coordination_table.txt`)
  • Getting cost/token summaries (in `metrics_summary.json`)

**Use Logfire When:**

  • You need precise timing data with millisecond accuracy
  • Analyzing span hierarchy and parent-child relationships
  • Finding exceptions and error stack traces
  • Creating shareable trace links for collaboration
  • Querying across multiple sessions (e.g., "find all sessions with errors")
  • Real-time monitoring of running experiments

**Rate Limiting:** If Logfire returns a rate limit error, **wait up to 60 seconds and retry** rather than falling back to local logs. The rate limit resets quickly and Logfire data is worth waiting for when timing/hierarchy analysis is needed.

**Key Local Log Files:**

| File | Contains | |------|----------| | `status.json` | Real-time status with **agent reliability metrics** (enforcement events, buffer loss) | | `metrics_summary.json` | Cost, tokens, tool stats, round history | | `coordination_events.json` | Full event timeline with tool calls | | `coordination_table.txt` | Human-readable coordination flow | | `streaming_debug.log` | Raw streaming data including command strings | | `agent_*/*/vote.json` | Vote reasoning and context | | `agent_*/*/execution_trace.md` | **Full tool calls, arguments, results, and reasoning** - invaluable for debugging | | `execution_metadata.yaml` | Config and session metadata |

**Execution Traces (`execution_trace.md`):** These are the most detailed debug artifacts. Each agent snapshot includes an execution trace with:

  • Complete tool calls with full arguments (not truncated)
  • Full tool results (not truncated)
  • Reasoning/thinking blocks from the model
  • Timestamps and round markers

Use execution traces when you need to understand exactly what an agent did and why - they capture everything the agent saw and produced during that answer/vote iteration.

**Enforcement Reliability (`status.json`):** The `status.json` file includes per-agent reliability metrics that track workflow enforcement events:

{
  "agents": {
    "agent_a": {
      "reliability": {
        "enforcement_attempts": [
          {
            "round": 0,
            "attempt": 1,
            "max_attempts": 3,
            "reason": "no_workflow_tool",
            "tool_calls": ["search", "read_file"],
            "error_message": "Must use workflow tools",
            "buffer_preview": "First 500 chars of lost content...",
            "buffer_chars": 1500,
            "timestamp": 1736683468.123
          }
        ],
        "by_round": {"0": {"count": 2, "reasons": ["no_workflow_tool", "invalid_vote_id"]}},
        "unknown_tools": ["execute_command"],
        "workflow_errors": ["inval
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