Plain MCP server for AI agents and assistants

Securely connect your AI agents and chatbots (Claude, ChatGPT, Cursor, etc) with Plain MCP or direct API to triage support conversations, label and prioritize tickets, draft customer replies, and automate inbox workflows through natural language.

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Plain is a collaborative support platform for B2B teams, focused on consolidating conversations and boosting efficiency with AI. Enjoy streamlined, modern workflows to assist customers across channels from one place.

22 Tools

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Type what you want done — sign in and watch it run live in the Tool Router playground.

TOOL ROUTER PLAYGROUND
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TOOLS

Supported Tools

Every Plain action and event your agent gets out of the box.

Add Customer To Group

Tool to add a customer to one or more customer groups.

Create Customer Group

Creates a new customer group in Plain for organizing and segmenting customers.

Create Thread

Tool to create a new thread.

Delete Customer

Tool to delete a customer from the system.

Delete User

Tool to delete a user from the system.

Fetch Company

Tool to fetch company details by ID.

Fetch Issues

Fetches external issue tracker links (Jira, Linear, GitHub, etc.

Fetch Tier

Tool to fetch a tier by its ID.

Get Customer By Email

Fetch customer details by email address.

Get Customer By ID

Tool to retrieve details of a specific customer by their unique ID.

Get Customers

Tool to fetch a list of customers.

Get Thread By ID

Fetches comprehensive details of a specific thread by ID, including customer info, status, priority, labels, and assignments.

Get User By ID

Fetch workspace user/team member by ID.

List Customer Groups

Tool to list all customer groups.

List Tiers

Tool to retrieve a list of tiers with pagination.

List Threads

Tool to retrieve a paginated list of threads.

Remove Customer From Group

Removes a customer from one or more customer groups in Plain.

Run GraphQL Query

Execute any GraphQL query or mutation against Plain API.

Send Message

Tool to send a new message within a thread.

Update Company

Upserts (creates or updates) a company in Plain.

Update Thread

Tool to update a thread's title.

Upsert Customer

Tool to upsert (create or update) a customer.

SETUP GUIDE

Connect Plain MCP Tool with your Agent

1

Install Composio

typescript
npm install @composio/core ai @ai-sdk/mcp @ai-sdk/openai
Install the Composio SDK and your agent framework
2

Create a session with MCP enabled

typescript
import { Composio } from "@composio/core";

const composio = new Composio();
const { mcp } = await composio.create("your-user-id", {
  toolkits: ["plain"],
  mcp: true,
});
Create a session scoped to Plain and read its MCP URL and headers
3

Connect your agent to the MCP server

typescript
import { createMCPClient } from "@ai-sdk/mcp";
import { openai } from "@ai-sdk/openai";
import { generateText, stepCountIs } from "ai";

const client = await createMCPClient({
  transport: { type: "http", url: mcp.url, headers: mcp.headers },
});

const { text } = await generateText({
  model: openai("gpt-5.6-sol"),
  tools: await client.tools(),
  prompt: "Fetch all customer issues for Acme Corp",
  stopWhen: stepCountIs(10),
});

console.log(text);
await client.close();
Pass the session's MCP URL and headers to your agent and run a Plain request
SETUP GUIDE

Connect Plain API Tool with your Agent

1

Install Composio

typescript
npm install @composio/core @composio/openai openai
Install the Composio SDK, the OpenAI provider, and the OpenAI SDK
2

Create a Composio session

typescript
import OpenAI from "openai";
import { Composio } from "@composio/core";
import { OpenAIResponsesProvider } from "@composio/openai";

const composio = new Composio({ provider: new OpenAIResponsesProvider() });
const client = new OpenAI();

const session = await composio.create("your-user-id", { toolkits: ["plain"] });
const tools = await session.tools();
Initialize Composio with the OpenAI Responses provider and create a session scoped to Plain
3

Run Plain tools with your agent

typescript
let response = await client.responses.create({
  model: "gpt-5.6-sol",
  tools,
  input: [{ role: "user", content: "Fetch all customer issues for Acme Corp" }],
});

while (response.output.some((o) => o.type === "function_call")) {
  const outputs = await composio.provider.handleToolCalls(session, response.output);
  response = await client.responses.create({
    model: "gpt-5.6-sol",
    tools,
    previous_response_id: response.id,
    input: outputs,
  });
}

console.log(response.output_text);
Send a request, execute the Plain tool calls through the session, and print the final answer

Why Use Composio?

AI Native Plain Integration

  • Supports both Plain MCP and direct API based integrations
  • Structured, LLM-friendly schemas for reliable tool execution
  • Rich coverage for reading, writing, and querying your Plain data

Managed Auth

  • Built-in API key management with secure storage
  • Central place to manage, scope, and revoke Plain access
  • Per user and per environment credentials instead of hard-coded keys

Agent Optimized Design

  • Tools are tuned using real error and success rates to improve reliability over time
  • Comprehensive execution logs so you always know what ran, when, and on whose behalf

Enterprise Grade Security

  • Fine-grained RBAC so you control which agents and users can access Plain
  • Scoped, least privilege access to Plain resources
  • Full audit trail of agent actions to support review and compliance

Rolling this out across your team?

Give your team centralized access control across every framework with Composio’s MCP Gateway.

EXPLORE MCP GATEWAY
FAQ

Frequently asked questions

Yes, Plain requires you to configure your own API key credentials. Once set up, Composio handles secure credential storage and API request handling for you.

Yes! Composio's Tool Router enables agents to use multiple toolkits. Learn more.

Yes. Composio is SOC 2 Type II compliant and is built to keep your Plain connection and credentials secure. OAuth tokens and API keys are encrypted, and sensitive customer data is protected at rest and in transit.

Composio also undergoes independent security testing and continuously monitors its systems for security threats. You can review the latest reports and policies in the Composio Trust Center.

Composio maintains and updates all toolkit integrations automatically, so your agents always work with the latest API versions.

Create the key in your Plain account settings, then paste it once on Composio's connection page. Composio stores it encrypted and uses it only for the Plain actions your agent runs. Nobody else in your workspace can read it, and you can revoke it inside Plain at any time.

When you connect a Plain account through Composio, every action runs under that account, so anything the agent creates, sends, or changes shows up in Plain as done by you. Keep an approval step in your prompt for actions with side effects, such as sending or deleting, and have the agent draft first.

Whatever the credentials you connect allow inside Plain. If Plain lets you scope a key to specific permissions, create a scoped one so the agent can only do what you intend. You can revoke the key inside Plain at any time.

Yes. Composio supports multiple connected accounts for the same app, and that works in Claude, ChatGPT, or any other assistant you connect through Composio. Give each Plain connection a name such as work or personal, and the assistant uses the one you mention in the request. Each account keeps its own credentials and nothing is merged.

The connection stops working the moment Plain rejects the old key. Create a new key in Plain and reconnect the account from the Composio dashboard or by asking your agent to reconnect Plain. Nothing else changes.

Composio's free Hobby plan includes 100,000 tool calls per month with no credit card, which covers most personal Plain use. Paid plans add higher limits and team features. Your Plain plan and its API limits still apply as usual.

Built-in connectors usually give one AI access to a limited set of apps. Many people use Composio because it lets their AI connect to more apps than it normally supports, or connect to multiple accounts for the same app (e.g. connect Claude to multiple Plain accounts).

With Composio, you connect Plain once and then use it across different AI assistants without setting it up separately in each one. Connect your apps to Composio once, then connect Composio to whichever AI you use, whether that's Claude, ChatGPT, Hermes, or your own custom assistant.

Start with Plain.It takes 30 seconds.

Managed auth, hosted MCP servers, and every Plain tool your agent needs.Free to start.

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