LangChain

Atomic Mail ships LangChain integrations for both runtimes, built from the same release and published at the same version:

Language	Package	Install
JavaScript / TypeScript	@atomicmail/langchain (npm)	npm install @atomicmail/langchain
Python	langchain-atomicmail (PyPI)	pip install langchain-atomicmail

Both expose the same three tools — register, jmap_request, help — over the same shared runtime that backs MCP and AgentSkill, so behavior does not drift between them.

Auth model

Proof of work — the agent owns its own inbox, no human sign-in. register performs PoW signup and the shared runtime rotates session and capability tokens for you; the underlying HTTP chain is REST authentication. If a person should own the mailbox and authorize your app instead, use OAuth 2.0 with a plain HTTP client.

Install and use

npm install @atomicmail/langchain

It provides both a ready-to-use tools array (createAtomicMailTools) and a toolkit class (AtomicMailToolkit).

Tool surfaces

import { createAtomicMailTools, AtomicMailToolkit } from "@atomicmail/langchain";

const tools = await createAtomicMailTools();

const toolkit = await AtomicMailToolkit.create();
const registerTool = toolkit.registerTool;
const jmapTool = toolkit.jmapRequestTool;
const helpTool = toolkit.helpTool;

Example

import { createAtomicMailTools } from "@atomicmail/langchain";

const [register, jmapRequest, help] = await createAtomicMailTools();

await register.invoke({ username: "myagent" });

const inbox = await jmapRequest.invoke({
  ops_file: "list_inbox.json",
});

const docs = await help.invoke({ topic: "presets" });
console.log(inbox, docs);

pip install langchain-atomicmail

Published on PyPI as langchain-atomicmail, released alongside the npm package at the same version. It bundles the Python Atomic Mail runtime, so it is the only install you need — there is no separate atomicmail package to add.

The same three tools, the same credential directory, and the same ATOMIC_MAIL_* environment variables listed above apply.

Available tools

Tool	Purpose
register	PoW signup / idempotent register with optional forced and credentials_dir.
jmap_request	Run JMAP request from ops or ops_file with vars and optional attachments.
help	Return built-in docs topics bundled with the package.

Same behavior as MCP and AgentSkill

The LangChain tools share the runtime with the other wrappers, so:

• register idempotency and forced semantics are delegated to shared AgentSession.register
• exactly one of ops or ops_file is required for jmap_request
• dry_run with attachments is rejected
• user vars are validated with ^[A-Z][A-Z0-9_]*$
• post-register flow includes cron guidance (help topic cron)

Credentials and environment

The same environment as the other wrappers:

• credential directory: ATOMIC_MAIL_CREDENTIALS_DIR or ~/.atomicmail
• API key override: ATOMIC_MAIL_API_KEY

credentials_dir can be passed per tool call for multi-account use.

Related

Raw JMAP requestsThe method shapes jmap_request sendsAgentic coreThe shared runtime both packages build onn8nCommunity node, proof-of-work pathDifyMarketplace plugin, proof-of-work pathHosted MCP serverOne URL for chat hosts