Files
Hunter Lovell ca5cc0acfb chore: merge alpha into main (#404)
* Revert "revert: "feat(deepagents): support multimodal files for backends (#298)" (#352)" (#353)

This reverts commit 03ea1c9729.

* revert: "revert: "feat(sdk): add async subagent middleware for remote LangGraph servers  (#323)" (#351)" (#354)

* Revert "revert: "feat(sdk): add async subagent middleware for remote LangGraph servers  (#323)" (#351)"

This reverts commit 367e43a5ed.

* use any backend protocol

* Reapply "chore(deepagents): refactor backend method names - `lsInfo` -> `ls`, …" (#349) (#356)

This reverts commit 573479d743.

* Reapply "chore(sdk): unify sync subagents and async subagents into a single pr…" (#348) (#355)

This reverts commit 96dc34ccb6.

* chore: align alpha with main (#358)

* fix(deepagents): remove orphaned ToolMessages for Gemini compatibility (#335)

* fix(deepagents): remove orphaned ToolMessages for Gemini compatibility

* Fix ToolMessages for Gemini compatibility

---------

Co-authored-by: Christian Bromann <git@bromann.dev>

* fix(deepagents): throw on built-in tool collision (#330)

* add error

* Create big-horses-fail.md

* add config error class

* cr

---------

Co-authored-by: Christian Bromann <git@bromann.dev>

* fix(deepagents): use `crypto.randomUUID()` instead of uuid (#336)

* fix(deepagents): use crypto.randomUUID() instead of uuid

* update pnpm-lock

* Create grumpy-weeks-wave.md

* Update libs/deepagents/src/middleware/fs.int.test.ts

* feat(deepagent): add LangSmithSandbox (#324)

* feat(deepagent): add LangSmithSandbox

* Change deepagents version from patch to minor

* format

* fix tests

* format

* make it a patch

* cr

* cr

* fix

* cr

* chore: version packages (#321)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

* regen lockfile

* fix langsmith tests so that they use backend protocol v2 methods

* format

---------

Co-authored-by: pawel-twardziak <pawel.twardziak.dev@gmail.com>
Co-authored-by: Christian Bromann <git@bromann.dev>
Co-authored-by: Maahir Sachdev <maahir.sachdev@langchain.dev>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

* feat(deepagents): add completion notifier middleware for async subagents (#334)

Port of langchain-ai/deepagents#2119 to TypeScript. Adds a
createCompletionNotifierMiddleware that async subagents can use to
proactively notify their supervisor when they complete or error,
closing the gap where the supervisor only learns about completion
when someone calls check_async_task.

- New createCompletionNotifierMiddleware with afterAgent and
  wrapModelCall hooks
- Uses @langchain/langgraph-sdk Client to send runs.create() to the
  supervisor's thread
- Reads parent_thread_id from subagent state (injected by
  start_async_task)
- Derives task_id from runtime.configurable.thread_id
- Silently no-ops if parent context is missing
- Guards against duplicate notifications
- 22 unit tests covering all hooks, edge cases, and error paths

fix(deepagents): make url required in completion notifier (no ASGI in JS)

JS does not have ASGI transport like Python, so the url parameter
must be provided explicitly. Removed all ASGI references from docs
and the localhost fallback default.

fix(deepagents): throw on built-in tool collision (#330)

* add error

* Create big-horses-fail.md

* add config error class

* cr

---------

Co-authored-by: Christian Bromann <git@bromann.dev>

fix(deepagents): use `crypto.randomUUID()` instead of uuid (#336)

* fix(deepagents): use crypto.randomUUID() instead of uuid

* update pnpm-lock

* Create grumpy-weeks-wave.md

* Update libs/deepagents/src/middleware/fs.int.test.ts

feat(deepagent): add LangSmithSandbox (#324)

* feat(deepagent): add LangSmithSandbox

* Change deepagents version from patch to minor

* format

* fix tests

* format

* make it a patch

* cr

* cr

* fix

* cr

regen lockfile

linting

linting

add missing url property

chore: version packages (#321)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

changeset

regen lockfil

* chore: enter alpha pre-release

* chore: target alpha for releases

* chore: version packages (alpha) (#359)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

* chore(deepagents): extend supported backend file types (#363)

* extend supported file types

* Create strong-tigers-share.md

---------

Co-authored-by: Hunter Lovell <40191806+hntrl@users.noreply.github.com>

* chore(deepagents): implement async subagents + use stream example (#360)

* async subagents + use stream example

* fix lockfile

* format

* linting

* readme and linting

* format

* proactively send responses when subagents complete

* better examples

* feat(deepagents): rename completion notifier to completion callback and align with Python (#361)

* feat(deepagents): rename completion notifier to completion callback and align with Python PR

- Rename completion_notifier.ts -> completion_callback.ts to match Python's
  completion_callback.py naming
- Rename exports: createCompletionNotifierMiddleware -> createCompletionCallbackMiddleware,
  CompletionNotifierOptions -> CompletionCallbackOptions
- Rename state key: parent_thread_id -> callbackThreadId, option: parentGraphId -> callbackGraphId
- Make url optional (Python allows omitting for ASGI transport)
- Match Python's strict error behavior: throw on empty messages, non-AIMessage types,
  and missing callbackThreadId
- Add truncation suffix with task_id hint for long messages
- Use generic error message in wrapModelCall (don't leak error details)
- Remove duplicate notification guard (Python notifies on every error)
- Add extractCallbackContext to async_subagents.ts: injects callbackThreadId
  into subagent input state when launching via start_async_task
- Add tests for extractCallbackContext and callback context injection

* cr

* Rename completion notifier to completion callback

Renamed completion notifier to completion callback for consistency with Python.

* fix(sdk): `AsyncTask` `updatedAt` field doesn't update on task status changes (#400)

* update updatedAt field to change on any task update

* added changeset

* chore: set up self hosted async subagent example (#399)

* self hosted async subagent example

* with postgres

* formatting

* eslint disable no console

* fix dockerfile and readme

* Update examples/async-subagent-server/server.ts

Co-authored-by: Christian Bromann <git@bromann.dev>

---------

Co-authored-by: Christian Bromann <git@bromann.dev>

* chore(sdk): update async subagent middleware for agent protocol (#394)

* update async subagent middleware for agent protocol

* add changeset

* Update libs/deepagents/src/middleware/async_subagents.ts

Co-authored-by: Hunter Lovell <40191806+hntrl@users.noreply.github.com>

* Update libs/deepagents/src/middleware/async_subagents.ts

Co-authored-by: Hunter Lovell <40191806+hntrl@users.noreply.github.com>

* Update libs/deepagents/src/middleware/async_subagents.ts

Co-authored-by: Hunter Lovell <40191806+hntrl@users.noreply.github.com>

* differentiate agent protocol

---------

Co-authored-by: Hunter Lovell <40191806+hntrl@users.noreply.github.com>

* chore(repo): migrate linting and formatting to oxc tooling (#391)

* chore(repo): migrate linting and formatting to oxc tooling

* cr

* cr

* chore(lint): clean up console disables for oxlint

* cr

* Apply suggestions from code review

Co-authored-by: Christian Bromann <git@bromann.dev>

---------

Co-authored-by: Christian Bromann <git@bromann.dev>

* refactor(deepagents): clean up createDeepAgent middleware wiring (#392)

* refactor(deepagents): clean up createDeepAgent middleware wiring

* fix(deepagents): avoid duplicate HITL middleware on subagents

* add comments, remove iife

* Create ten-masks-flow.md

* fix(deepagents): align prompt templates with runtime behavior (#393)

* fix(deepagents): align prompt templates with runtime behavior

* chore: add changeset for prompt alignment fixes

* cr

* cr

* fix store backend and tests

* lint

* fix rests and resolveBackend

* lint

* fix failing tests

* revert adapt resolve backend

* fix resolve backend

* better variable name

* fix backend factory to return a maybe promise

* mark resolve backend as internal

* format

---------

Co-authored-by: Colin Francis <131073567+colifran@users.noreply.github.com>
Co-authored-by: pawel-twardziak <pawel.twardziak.dev@gmail.com>
Co-authored-by: Christian Bromann <git@bromann.dev>
Co-authored-by: Maahir Sachdev <maahir.sachdev@langchain.dev>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Colin Francis <colin.francis@langchain.dev>
2026-04-01 17:10:16 -07:00
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Async Subagent Server

A self-hosted Agent Protocol server that exposes a DeepAgents researcher as an async subagent. Use this as a starting point for hosting your own agent on any infrastructure and connecting it to a DeepAgents supervisor.

The example includes both sides of the pattern:

  • server.ts — the Hono server your subagent runs on
  • supervisor.ts — an interactive REPL showing how to connect to it

Prerequisites

  • ANTHROPIC_API_KEY — required
  • TAVILY_API_KEY — optional; stub search is used if not set

Quickstart

1. Install and build (from the repo root):

pnpm install
pnpm --filter deepagents build

2. Set up your environment:

cd examples/async-subagent-server
cp .env.example .env
# fill in ANTHROPIC_API_KEY (and optionally TAVILY_API_KEY)

3. Start the server and Postgres:

docker compose up

4. In another terminal, start the supervisor:

cd examples
tsx async-subagent-server/supervisor.ts

Try these prompts:

> research the latest developments in quantum computing
> check status of <task-id>
> update <task-id> to focus on commercial applications only
> cancel <task-id>
> list all tasks

Run locally (bring your own Postgres)

If you already have Postgres running, skip Docker Compose and point the server at your database:

cd examples
DATABASE_URL=postgres://user:pass@localhost:5432/agentdb tsx async-subagent-server/server.ts

The server creates the threads and runs tables automatically on startup.

Then start the supervisor in another terminal:

cd examples
tsx async-subagent-server/supervisor.ts

Run with Docker (server only)

Build from the repo root (required because deepagents is a workspace dependency):

docker build -f examples/async-subagent-server/Dockerfile -t async-subagent-server .

docker run -p 2024:2024 \
  -e ANTHROPIC_API_KEY=your-key \
  -e TAVILY_API_KEY=your-key \
  -e DATABASE_URL=postgres://user:pass@your-db-host:5432/agentdb \
  async-subagent-server

Implemented endpoints

These are the Agent Protocol endpoints the DeepAgents async subagent middleware calls:

Endpoint Purpose
POST /threads Create a thread for a new task
POST /threads/:threadId/runs Start or interrupt+restart a run
GET /threads/:threadId/runs/:runId Poll run status
GET /threads/:threadId/state Fetch final output
POST /threads/:threadId/runs/:runId/cancel Cancel a run
GET /ok Health check

Swap in your own agent

Replace the createDeepAgent call in server.ts with your own agent. The Agent Protocol layer stays the same regardless of what the agent does.

const agent = createDeepAgent({
  systemPrompt: "You are a ...",
  tools: [yourTool],
});