OpenAgentsControl/evals/framework/src/logging/README.md

Multi-Agent Logging System

Status: ✅ COMPLETE - All 3 Days Implemented
Date: 2025-12-17
Version: 1.0.0

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Overview

A modular logging system for tracking and visualizing multi-agent delegation hierarchies in the eval framework. Provides clear visual output showing parent-child relationships, delegation chains, and session activity.

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Features

✅ Session Hierarchy Tracking - Tracks parent → child → grandchild relationships
✅ Visual Formatting - Pretty-printed output with indentation and emojis
✅ Delegation Events - Captures when agents delegate to subagents
✅ Message Logging - Logs user and assistant messages at all levels
✅ Tool Call Tracking - Shows tool usage with relevant details
✅ Tree Analysis - Build complete session trees with statistics

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Architecture

evals/framework/src/logging/
├── types.ts              # TypeScript interfaces
├── session-tracker.ts    # Session hierarchy tracking
├── logger.ts             # Pretty-printing logger
├── formatters.ts         # Visual formatting utilities
├── index.ts              # Module exports
└── __tests__/            # Unit and integration tests
    ├── session-tracker.test.ts
    ├── logger.test.ts
    └── integration.test.ts

---

Usage

Basic Example

import { MultiAgentLogger } from './logging/index.js';

// Create logger (enabled, verbose)
const logger = new MultiAgentLogger(true, false); // Non-verbose mode
// const logger = new MultiAgentLogger(true, true); // Verbose mode (debug)

// Log parent session
logger.logSessionStart('ses_parent_123', 'openagent');
logger.logMessage('ses_parent_123', 'user', 'Call subagent');

// Log delegation
const delegationId = logger.logDelegation(
  'ses_parent_123',
  'simple-responder',
  'Respond with test message'
);

// Log child session
logger.logSessionStart('ses_child_456', 'simple-responder', 'ses_parent_123');
logger.logChildLinked(delegationId, 'ses_child_456');

// Log child activity
logger.logMessage('ses_child_456', 'assistant', 'AWESOME TESTING');

// Complete sessions
logger.logSessionComplete('ses_child_456');
logger.logSessionComplete('ses_parent_123');

Output (Verbose Mode - Debug)

┌────────────────────────────────────────────────────────────┐
│ 🎯 PARENT: openagent (ses_parent_1...)                     │
└────────────────────────────────────────────────────────────┘
  📝 User: Call subagent

  🔧 TOOL: task
     ├─ subagent: simple-responder
     ├─ prompt: Respond with test message
     └─ Creating child session...

  ┌────────────────────────────────────────────────────────────┐
  │ 🎯 CHILD: simple-responder (ses_child_45...)               │
  │    Parent: ses_parent_1...                                 │
  │    Depth: 1                                                │
  └────────────────────────────────────────────────────────────┘
     └─ Child session: ses_child_45...
    🤖 Agent: AWESOME TESTING
  ✅ CHILD COMPLETE (2.5s)

✅ PARENT COMPLETE (29.4s)

Output (Non-Verbose Mode - Default)

Running tests...

   → Child agent started (session: ses_child_45...)
   ✓ Child agent completed (OpenAgent, 2.5s)

Running evaluator: approval-gate...

In non-verbose mode, only child session lifecycle events are shown, providing visibility into delegation without overwhelming output.

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API Reference

MultiAgentLogger

Main logger class with hierarchy-aware formatting.

Methods

logSessionStart(sessionId, agent, parentId?)
Log session creation. Automatically tracks hierarchy.

logDelegation(parentSessionId, toAgent, prompt)
Log delegation event. Returns delegation ID.

logChildLinked(delegationId, childSessionId)
Link child session to delegation event.

logMessage(sessionId, role, text)
Log user or assistant message.

logToolCall(sessionId, tool, input)
Log tool execution (skips 'task' tool).

logSessionComplete(sessionId)
Mark session as complete with duration.

logSystem(sessionId, message)
Log system message.

getTracker()
Get SessionTracker for analysis.

setEnabled(enabled)
Enable/disable logging.

clear()
Clear all tracked data.

---

SessionTracker

Tracks session hierarchy and delegation events.

Methods

registerSession(sessionId, agent, parentId?)
Register new session in hierarchy.

recordDelegation(parentSessionId, toAgent, prompt)
Record delegation event. Returns delegation ID.

linkChildSession(delegationId, childSessionId)
Link child session to delegation.

completeSession(sessionId)
Mark session complete.

getSession(sessionId)
Get session node by ID.

getHierarchy(rootSessionId)
Get full hierarchy from root.

buildTree(rootSessionId)
Build complete session tree with stats.

getSessionsAtDepth(depth)
Get all sessions at specific depth.

getRootSessions()
Get all root sessions (depth 0).

getDelegationsFromSession(sessionId)
Get all delegations from a session.

clear()
Clear all tracked data.

---

Testing

Run Tests

# All logging tests
npm test -- src/logging/__tests__/ --run

# Specific test file
npm test -- src/logging/__tests__/session-tracker.test.ts --run

# Integration tests
npm test -- src/logging/__tests__/integration.test.ts --run

Test Coverage

• ✅ 37 tests passing
• ✅ SessionTracker: 16 tests
• ✅ MultiAgentLogger: 18 tests
• ✅ Integration: 3 tests

Demo Script

npx tsx scripts/demo-logging.ts

Shows realistic delegation scenario with visual output.

---

Implementation Status

✅ Day 1: Core Infrastructure (COMPLETE)

• Create logging directory structure
• Implement types.ts
• Implement session-tracker.ts
• Implement logger.ts
• Implement formatters.ts
• Create index.ts exports
• Write unit tests (37 tests)
• TypeScript build validation
• Integration tests
• Demo script

✅ Day 2: Event Stream Integration (COMPLETE)

• Modify event-stream-handler.ts
• Hook into session.created events
• Hook into message.updated events
• Hook into message.part.updated events
• Initialize logger in test-runner.ts
• Test with simple-subagent-call.yaml

✅ Day 3: Child Session Capture (COMPLETE)

• Implement child session detection
• Track multiple active sessions
• Capture child session messages from text parts
• Link child sessions to parent delegations
• Test with nested delegation
• Message deduplication for cleaner output

---

Design Principles

Modular: Each component has single responsibility
Functional: Pure functions, immutable data
Testable: 100% test coverage, easy to mock
Visual: Clear hierarchy with indentation
Performant: Minimal overhead (<5% target)

---

Examples

Nested Delegation (3 Levels)

logger.logSessionStart('root', 'openagent');
logger.logDelegation('root', 'task-manager', 'Break down feature');
logger.logSessionStart('level1', 'task-manager', 'root');
logger.logDelegation('level1', 'coder-agent', 'Implement subtask');
logger.logSessionStart('level2', 'coder-agent', 'level1');

Output shows 3 levels of indentation with clear parent-child links.

Parallel Delegation

logger.logSessionStart('parent', 'openagent');
logger.logDelegation('parent', 'tester', 'Write tests');
logger.logDelegation('parent', 'reviewer', 'Review code');
logger.logSessionStart('tester', 'tester', 'parent');
logger.logSessionStart('reviewer', 'reviewer', 'parent');

Both children shown at same depth level.

---

Next Steps

1. Integrate into event stream handler (Day 2)

   • Hook logger into SDK event stream
   • Detect session creation, messages, tool calls
   • Test with existing eval tests

2. Implement child session monitoring (Day 3)

   • Monitor for child session creation
   • Fetch child messages via SDK
   • Link child timeline to parent

3. Add to all evaluators (Future)

   • Enable logging in debug mode
   • Export logs to JSON
   • Build log viewer dashboard

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Related Files

• Task Spec: tasks/eval/december/01-multi-agent-logging-system.md
• Checklist: tasks/eval/december/CHECKLIST.md
• Analysis: evals/EVAL_SYSTEM_ANALYSIS.md
• Action Plan: evals/ACTION_PLAN.md

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Created: 2025-12-17
Author: OpenAgent
Status: Day 1 Complete ✅