Multi-Agent Orchestration — Getting Multiple AI Agents to Collaborate on Complex Tasks

A single Agent can do a lot. But truly complex scenarios — like a project that needs simultaneous code review, security audit, and documentation — quickly overwhelm one Agent's context window and attention.

That's what multi-agent orchestration solves. Not making one Agent stronger, but making multiple Agents each do what they do best.

Why Multi-Agent

Problem Single Agent Multi-Agent
Context window One window for everything Independent windows per Agent
Depth of expertise Jack of all trades Each Agent specializes
Parallelism Sequential only Multiple Agents work simultaneously
Fault tolerance One failure = total failure Individual Agent failure is isolated

Two Classic Orchestration Patterns

Pattern 1: Sequential Pipeline

Agent A's output feeds into Agent B. Like a factory assembly line.

Typical use case: Code generation → Code review → Security scan → Documentation.

def sequential_pipeline(task: str) -> str:
    # Agent 1: Generate code
    code = agent_coder.run(f"Implement: {task}")

    # Agent 2: Review code
    review = agent_reviewer.run(f"Review this code:\n{code}")
    if "needs changes" in review.lower():
        code = agent_coder.run(f"Fix based on feedback:\n{review}\nCode:\n{code}")

    # Agent 3: Security scan
    security = agent_security.run(f"Scan for vulnerabilities:\n{code}")

    # Agent 4: Generate docs
    docs = agent_writer.run(f"Write documentation for:\n{code}")

    return {"code": code, "review": review,
            "security": security, "docs": docs}
📌 When to use: Tasks have clear sequential dependencies. Later steps are meaningless without earlier ones.

Pattern 2: Parallel Fan-Out

Multiple Agents tackle different sub-tasks simultaneously, then aggregate.

Typical use case: Market analysis — Agent A does technicals, Agent B fundamentals, Agent C sentiment, then consolidate.

import concurrent.futures

def parallel_orchestration(market: str) -> dict:
    tasks = {
        "technical": f"Analyze {market} technical indicators (MACD, RSI, MAs)",
        "fundamental": f"Analyze {market} fundamentals (valuation, earnings, growth)",
        "sentiment": f"Analyze {market} sentiment and news",
        "flow": f"Analyze {market} capital flows and positioning"
    }

    with concurrent.futures.ThreadPoolExecutor() as executor:
        futures = {
            name: executor.submit(agent_analyst.run, prompt)
            for name, prompt in tasks.items()
        }
        results = {
            name: future.result()
            for name, future in futures.items()
        }

    # Summarizer Agent consolidates all analyses
    summary = agent_summarizer.run(
        f"Synthesize the following analyses into a conclusion:\n" +
        "\n".join([f"## {k}\n{v}" for k, v in results.items()])
    )
    return {"analysis": results, "summary": summary}

MCP: A Common Language for Agents

MCP (Model Context Protocol) is an open protocol from Anthropic that solves a key problem: how to standardize tool and context sharing between Agents.

The old problem: Agent A's tools can't be used by Agent B. Agent B's context can't be read by Agent C. Every Agent is an information silo.

MCP's three core concepts:

  1. Server — provides tools and resources. E.g., a "GitHub Server" offers tools for reading PRs and checking issues
  2. Client — the Agent framework, connecting to multiple MCP Servers via standard protocol
  3. Transport — communication method: stdio (local processes) or HTTP (remote services)
# mcp_config.yaml — Agent framework configuration
servers:
  filesystem:
    command: "npx"
    args: ["-y", "@anthropic/mcp-server-filesystem", "/workspace"]
  github:
    command: "npx"
    args: ["-y", "@anthropic/mcp-server-github"]
    env:
      GITHUB_TOKEN: "${GITHUB_TOKEN}"
  database:
    url: "https://db-mcp.internal/mcp"
    transport: "http"

Once configured, the Agent automatically gets all the tools these Servers provide — file search, PR reading, database querying — no per-tool integration code needed.

How to Evaluate Agent Systems

Agents aren't classifiers — you can't measure them with accuracy. You need multi-dimensional evaluation:

Dimension How to Measure Metric
Task completion Give 100 standard tasks, count completions Completion rate %
Tool call accuracy Verify each tool call is correct Correct calls / total
Efficiency Turns and tokens used per task Avg turns, token cost
Self-healing rate Percentage of errors recovered autonomously Recoveries / errors
Security Inject malicious prompts, check if blocked Block rate %
def evaluate_agent(agent, test_suite: list[dict]) -> dict:
    """Basic Agent evaluation framework."""
    results = {"passed": 0, "failed": 0, "details": []}

    for case in test_suite:
        try:
            output = agent.run(case["input"])
            # Use another Agent or rules to judge pass/fail
            verdict = judge_agent.run(
                f"Task: {case['input']}\n"
                f"Expected: {case['expected']}\n"
                f"Actual: {output}\n"
                f"Judge if this passes (reply PASS or FAIL)"
            )
            passed = "PASS" in verdict.upper()
            results["passed" if passed else "failed"] += 1
            results["details"].append({
                "task": case["name"],
                "passed": passed,
                "verdict": verdict
            })
        except Exception as e:
            results["failed"] += 1
            results["details"].append({
                "task": case["name"], "passed": False, "error": str(e)
            })

    return results

Production Deployment Checklist

Layer What to Do
Sandboxing Agent code execution MUST run in Docker/VM sandboxes, never on bare host
Rate limiting Set per-user/per-Agent API call caps to prevent runaway costs
Audit logging Log every Agent's tool calls, parameters, and results for post-hoc analysis
Observability Real-time monitoring of Agent status, token consumption, error rates
Fallback When the Agent can't handle it, gracefully degrade to human review

Orchestration Golden Rules

  1. Use one if one is enough — multi-agent adds complexity and cost. Only go multi when a single Agent genuinely can't cut it.
  2. Use structured data between Agents — don't have one Agent output natural language and another guess the meaning. Use JSON, checklists, structured reports.
  3. Set global timeouts and budgets — with multiple Agents running in parallel, total token consumption can explode. Hard caps are non-negotiable.

📖 Next: Building an Agent Framework from Scratch — verifiable execution traces and sandbox security