1.4 — Multi-Agent Systems and Orchestration

CCAR-P Domain 1 · Task 1.4

What You Need to Know

When Multi-Agent Is Justified

Excels at breadth-first work that parallelises cleanly: research across independent directions, analysis of many independent units, tasks exceeding one context window, work needing distinct specialisms/tools/permissions.

Cost: ~15× tokens of chat. Value must pay for the multiplier.

Key Concept: Justify the architecture first. Multi-agent for a task one agent handles well is a wrong answer.

Orchestrator-Worker Architecture

• Subagents start with a fresh context (unless forked). Context must be passed explicitly.
• Delegation quality determines system quality. Effective brief: explicit objective, expected output format, tool/source guidance, clear task boundaries.

Failure Modes

Failure	Signature / Root cause
Narrow decomposition	Systematic gaps — coordinator's split incomplete
Duplicated work	Overlapping scopes — boundaries never partitioned
Effort mismatch	Too many agents for simple fact-check
Lost attribution	Findings as free prose lose sources

Duplication + gaps = unpartitioned coordinator decomposition.

Orchestration Strategy

• Parallel where independent, sequential where dependent
• Durable state and checkpointing
• Observability of agent decisions
• Through-the-coordinator is the default topology

Exam Traps

• Diagnosing overlapping/missing sections as a subagent capability problem
• Assuming subagents can see coordinator conversation or each other
• Proposing multi-agent for a task that fits one context window
• Fixing coverage gaps by adding more subagents (same briefs)