Complex tasks in Claude Code often take longer than necessary. Research, codebase exploration, multi-part analysis—much of this work could happen simultaneously, but by default, Claude works sequentially.
The good news: you can explicitly ask Claude Code to parallelize work using sub-agents. Here's how.
What Are Sub-Agents?
Sub-agents are separate Claude instances that the main agent spawns for specific jobs. Each operates in its own context window, works independently, and reports back with a summary when finished.
Think of it as delegating to a team: instead of one person doing five research tasks back-to-back, you assign each to a different team member working simultaneously.
When to Use Parallel Sub-Agents
Parallel sub-agents work best when:
- Tasks are independent. Each sub-agent can complete its work without needing results from the others.
- Work is self-contained. The task can be summarized usefully when complete.
- You're dealing with volume. Multiple similar tasks that would otherwise run sequentially.
Great use cases include:
- Competitive research across multiple companies
- Exploring different parts of a large codebase
- Analyzing multiple documents or data sources
- Running independent test suites or validations
- Researching multiple topics for a report
How to Request Parallel Sub-Agents
Claude Code uses sub-agents conservatively by default. To maximize parallelization, be explicit in your prompts.
Basic Approach
Tell Claude Code to use parallel tasks:
"Research these 5 companies in parallel using separate sub-agents: Acme Corp, Beta Industries, Gamma Tech, Delta Solutions, and Epsilon Labs. Each sub-agent should analyze market position, recent news, and competitive advantages."
Or for codebase exploration:
"Explore this codebase using 4 parallel tasks. Have each sub-agent focus on a different area: frontend components, backend APIs, database layer, and authentication system."
Detailed Approach
For complex workflows, provide explicit delegation instructions:
"I need competitive intelligence on our three main competitors. Use parallel sub-agents as follows:
Sub-agent 1: Research Competitor A—product roadmap, recent funding, customer reviews.
Sub-agent 2: Research Competitor B—same analysis.
Sub-agent 3: Research Competitor C—same analysis.
Once all three complete, synthesize findings into a comparison matrix."
What Happens Behind the Scenes
When Claude Code spawns sub-agents:
- Each gets its own isolated context window
- They work independently and simultaneously
- Each reports a summary back to the main agent when finished
- The main agent synthesizes the results for you
This isolation is a feature, not a limitation—it keeps your main conversation clean. Sub-agents can churn through thousands of tokens in their research; you see only the distilled results.
Practical Tips
Be specific about the number of sub-agents. "Use 5 parallel tasks" is clearer than "parallelize this work."
Define what each sub-agent should focus on. Clear scope prevents overlap and ensures comprehensive coverage.
Request synthesis at the end. Ask the main agent to combine findings into a unified summary, comparison, or recommendation.
Consider custom sub-agents for recurring workflows. You can define specialized agents (like a "competitive researcher" or "code reviewer") in your project's .claude/agents/ folder for reuse.
Limitations
A few constraints worth knowing:
- Sub-agents cannot spawn other sub-agents (no nesting)
- Results from multiple sub-agents can consume significant context when they all report back
- Sub-agents work best for read-heavy operations; parallel writes can cause conflicts
- Many simultaneous agents may hit API rate limits
The Bottom Line
If your work in Claude Code involves multiple independent tasks—research, exploration, analysis—you're leaving speed on the table without parallel sub-agents. The feature is already there; you just need to ask for it.
Next time you have a competitive analysis, a codebase to explore, or a multi-part research project, try adding "use parallel sub-agents" to your prompt. You might be surprised how much faster your workflows become.