Design optimal agent team compositions with sizing

Team Composition Patterns

Best practices for composing multi-agent teams, selecting team sizes, choosing agent types, and configuring display modes for Claude Code's Agent Teams feature.

When to Use This Skill

• Deciding how many teammates to spawn for a task
• Choosing between preset team configurations
• Selecting the right agent type (subagent_type) for each role
• Configuring teammate display modes (tmux, iTerm2, in-process)
• Building custom team compositions for non-standard workflows

Team Sizing Heuristics

Complexity	Team Size	When to Use
Simple	1-2	Single-dimension review, isolated bug, small feature
Moderate	2-3	Multi-file changes, 2-3 concerns, medium features
Complex	3-4	Cross-cutting concerns, large features, deep debugging
Very Complex	4-5	Full-stack features, comprehensive reviews, systemic issues

Rule of thumb: Start with the smallest team that covers all required dimensions. Adding teammates increases coordination overhead.

Preset Team Compositions

Review Team

• Size: 3 reviewers
• Agents: 3x team-reviewer
• Default dimensions: security, performance, architecture
• Use when: Code changes need multi-dimensional quality assessment

Debug Team

• Size: 3 investigators
• Agents: 3x team-debugger
• Default hypotheses: 3 competing hypotheses
• Use when: Bug has multiple plausible root causes

Feature Team

• Size: 3 (1 lead + 2 implementers)
• Agents: 1x team-lead + 2x team-implementer
• Use when: Feature can be decomposed into parallel work streams

Fullstack Team

• Size: 4 (1 lead + 3 implementers)
• Agents: 1x team-lead + 1x frontend team-implementer + 1x backend team-implementer + 1x test team-implementer
• Use when: Feature spans frontend, backend, and test layers

Research Team

• Size: 3 researchers
• Agents: 3x general-purpose
• Default areas: Each assigned a different research question, module, or topic
• Capabilities: Codebase search (Grep, Glob, Read), web search (WebSearch, WebFetch)
• Use when: Need to understand a codebase, research libraries, compare approaches, or gather information from code and web sources in parallel

Security Team

• Size: 4 reviewers
• Agents: 4x team-reviewer
• Default dimensions: OWASP/vulnerabilities, auth/access control, dependencies/supply chain, secrets/configuration
• Use when: Comprehensive security audit covering multiple attack surfaces

Migration Team

• Size: 4 (1 lead + 2 implementers + 1 reviewer)
• Agents: 1x team-lead + 2x team-implementer + 1x team-reviewer
• Use when: Large codebase migration (framework upgrade, language port, API version bump) requiring parallel work with correctness verification

Agent Type Selection

When spawning teammates with the Agent tool, choose subagent_type based on what tools the teammate needs:

Agent Type	Tools Available	Use For
general-purpose	All tools (Read, Write, Edit, Bash, etc.)	Implementation, debugging, any task requiring file changes
Explore	Read-only tools (Read, Grep, Glob)	Research, code exploration, analysis
Plan	Read-only tools	Architecture planning, task decomposition
agent-teams:team-reviewer	Read/search/Bash plus TaskList/TaskGet/TaskUpdate/SendMessage	Code review with structured findings
agent-teams:team-debugger	Read/search/Bash plus TaskList/TaskGet/TaskUpdate/SendMessage	Hypothesis-driven investigation
agent-teams:team-implementer	Read/Write/Edit/search/Bash plus TaskList/TaskGet/TaskUpdate/SendMessage	Building features within file ownership boundaries
agent-teams:team-lead	Read/search/Bash plus Agent Teams coordination tools	Team orchestration and coordination

Key distinction: Read-only agents (Explore, Plan) cannot modify files. Never assign implementation tasks to read-only agents.

Display Mode Configuration

Configure in ~/.claude/settings.json:

{
  "teammateMode": "tmux"
}

Mode	Behavior	Best For
"tmux"	Each teammate in a tmux pane	Development workflows, monitoring multiple agents
"iterm2"	Each teammate in an iTerm2 tab	macOS users who prefer iTerm2
"in-process"	All teammates in same process	Simple tasks, CI/CD environments

Custom Team Guidelines

When building custom teams:

1. Every team needs a coordinator — Either designate a team-lead or have the user coordinate directly
2. Match roles to agent types — Use specialized agents (reviewer, debugger, implementer) when available
3. Avoid duplicate roles — Two agents doing the same thing wastes resources
4. Define boundaries upfront — Each teammate needs clear ownership of files or responsibilities
5. Keep it small — 2-4 teammates is the sweet spot; 5+ requires significant coordination overhead

Troubleshooting

A teammate was spawned as Explore but needs to write files. Explore and Plan are read-only agents. Change the subagent_type to general-purpose or an appropriate specialized agent type. Never assign implementation tasks to read-only agents.

The team is growing too large and coordination is slowing everything down. Each additional teammate adds communication overhead. Consolidate roles: can one agent cover two dimensions? A 4-person team doing 6 independent tasks is usually better served by 3 agents covering 2 tasks each.

tmux mode is not showing panes. Ensure tmux is installed and a session is already running before spawning teammates. The in-process mode works without tmux and is suitable for CI or scripted environments.

Two reviewers are flagging the same issues. The review dimensions overlap. Redefine each reviewer's focus area: one on correctness/logic, one on security, one on performance/scalability. Overlapping coverage wastes tokens and produces duplicate findings.

A team-lead is spawning teammates but they are not receiving tasks. Verify that the lead is using the Agent tool to spawn teammates and passing complete context in the prompt. Teammates start fresh with no prior conversation history — they need all relevant information in their initial prompt.

Related Skills

• parallel-feature-development — Decompose work streams and assign file ownership once the team is composed
• team-communication-protocols — Establish messaging norms and shutdown procedures for the assembled team