Deep Agents Orchestration

<overview> Deep Agents include three orchestration capabilities:

1. SubAgentMiddleware: Delegate work via task tool to specialized agents
2. TodoListMiddleware: Plan and track tasks via write_todos tool
3. HumanInTheLoopMiddleware: Require approval before sensitive operations

All three are automatically included in create_deep_agent(). </overview>

Subagents (Task Delegation)

<when-to-use-subagents>

</when-to-use-subagents>

<how-subagents-work> Main agent has task tool -> creates fresh subagent -> subagent executes autonomously -> returns final report.

Default subagent: "general-purpose" - automatically available with same tools/config as main agent. </how-subagents-work>

<ex-custom-subagents> <python> Create a custom "researcher" subagent with specialized tools for academic paper search.

from deepagents import create_deep_agent
from langchain.tools import tool

@tool
def search_papers(query: str) -> str:
    """Search academic papers."""
    return f"Found 10 papers about {query}"

agent = create_deep_agent(
    subagents=[
        {
            "name": "researcher",
            "description": "Conduct web research and compile findings",
            "system_prompt": "Search thoroughly, return concise summary",
            "tools": [search_papers],
        }
    ]
)

# Main agent delegates: task(agent="researcher", instruction="Research AI trends")

</python> <typescript> Create a custom "researcher" subagent with specialized tools for academic paper search.

import { createDeepAgent } from "deepagents";
import { tool } from "@langchain/core/tools";
import { z } from "zod";

const searchPapers = tool(
  async ({ query }) => `Found 10 papers about ${query}`,
  { name: "search_papers", description: "Search papers", schema: z.object({ query: z.string() }) }
);

const agent = await createDeepAgent({
  subagents: [
    {
      name: "researcher",
      description: "Conduct web research and compile findings",
      systemPrompt: "Search thoroughly, return concise summary",
      tools: [searchPapers],
    }
  ]
});

// Main agent delegates: task(agent="researcher", instruction="Research AI trends")

</typescript> </ex-custom-subagents>

<ex-subagent-with-hitl> <python> Configure a subagent with HITL approval for sensitive operations.

from deepagents import create_deep_agent
from langgraph.checkpoint.memory import MemorySaver

agent = create_deep_agent(
    subagents=[
        {
            "name": "code-deployer",
            "description": "Deploy code to production",
            "system_prompt": "You deploy code after tests pass.",
            "tools": [run_tests, deploy_to_prod],
            "interrupt_on": {"deploy_to_prod": True},  # Require approval
        }
    ],
    checkpointer=MemorySaver()  # Required for interrupts
)

</python> </ex-subagent-with-hitl>

<fix-subagents-are-stateless> <python> Subagents are stateless - provide complete instructions in a single call.

# WRONG: Subagents don't remember previous calls
# task(agent='research', instruction='Find data')
# task(agent='research', instruction='What did you find?')  # Starts fresh!

# CORRECT: Complete instructions upfront
# task(agent='research', instruction='Find data on AI, save to /research/, return summary')

</python> <typescript> Subagents are stateless - provide complete instructions in a single call.

// WRONG: Subagents don't remember previous calls
// task research: Find data
// task research: What did you find?  // Starts fresh!

// CORRECT: Complete instructions upfront
// task research: Find data on AI, save to /research/, return summary

</typescript> </fix-subagents-are-stateless>

<fix-custom-subagents-dont-inherit-skills> <python> Custom subagents don't inherit skills from the main agent.

# WRONG: Custom subagent won't have main agent's skills
agent = create_deep_agent(
    skills=["/main-skills/"],
    subagents=[{"name": "helper", ...}]  # No skills inherited
)

# CORRECT: Provide skills explicitly (general-purpose subagent DOES inherit)
agent = create_deep_agent(
    skills=["/main-skills/"],
    subagents=[{"name": "helper", "skills": ["/helper-skills/"], ...}]
)

</python> </fix-custom-subagents-dont-inherit-skills>

TodoList (Task Planning)

<when-to-use-todolist>

</when-to-use-todolist>

<todolist-tool>

write_todos(todos: list[dict]) -> None

Each todo item has:

• content: Description of the task
• status: One of "pending", "in_progress", "completed"

</todolist-tool>

<ex-todolist-usage> <python> Invoke an agent that automatically creates a todo list for a multi-step task.

from deepagents import create_deep_agent

agent = create_deep_agent()  # TodoListMiddleware included by default

result = agent.invoke({
    "messages": [{"role": "user", "content": "Create a REST API: design models, implement CRUD, add auth, write tests"}]
}, config={"configurable": {"thread_id": "session-1"}})

# Agent's planning via write_todos:
# [
#   {"content": "Design data models", "status": "in_progress"},
#   {"content": "Implement CRUD endpoints", "status": "pending"},
#   {"content": "Add authentication", "status": "pending"},
#   {"content": "Write tests", "status": "pending"}
# ]

</python> <typescript> Invoke an agent that automatically creates a todo list for a multi-step task.

import { createDeepAgent } from "deepagents";

const agent = await createDeepAgent();  // TodoListMiddleware included

const result = await agent.invoke({
  messages: [{ role: "user", content: "Create a REST API: design models, implement CRUD, add auth, write tests" }]
}, { configurable: { thread_id: "session-1" } });

</typescript> </ex-todolist-usage>

<ex-access-todo-state> <python> Access the todo list from the agent's final state after invocation.

result = agent.invoke({...}, config={"configurable": {"thread_id": "session-1"}})

# Access todo list from final state
todos = result.get("todos", [])
for todo in todos:
    print(f"[{todo['status']}] {todo['content']}")

</python> </ex-access-todo-state>

<fix-todolist-requires-thread-id> <python> Todo list state requires a thread_id for persistence across invocations.

# WRONG: Fresh state each time without thread_id
agent.invoke({"messages": [...]})

# CORRECT: Use thread_id
config = {"configurable": {"thread_id": "user-session"}}
agent.invoke({"messages": [...]}, config=config)  # Todos preserved

</python> </fix-todolist-requires-thread-id>

Human-in-the-Loop (Approval Workflows)

<when-to-use-hitl>

</when-to-use-hitl>

<ex-hitl-setup> <python> Configure which tools require human approval before execution.

from deepagents import create_deep_agent
from langgraph.checkpoint.memory import MemorySaver

agent = create_deep_agent(
    interrupt_on={
        "write_file": True,  # All decisions allowed
        "execute_sql": {"allowed_decisions": ["approve", "reject"]},
        "read_file": False,  # No interrupts
    },
    checkpointer=MemorySaver()  # REQUIRED for interrupts
)

</python> <typescript> Configure which tools require human approval before execution.

import { createDeepAgent } from "deepagents";