MCP Server

MCP (Model Context Protocol) is an open standard that lets AI tools connect to external platforms. The Plain MCP server at https://mcp.plain.com/mcp lets tools like Claude, ChatGPT, and Cursor work with your support data directly instead of you copying and pasting between tabs.

You authenticate with your existing Plain account, so the MCP server has the same permissions as your user. No API keys needed. You can query threads, reply to customers, manage labels, and work with your help center, all from inside your AI tool.

Setup

ChatGPT

To use the Plain MCP in ChatGPT you will have to create an app, but first you may need to enable Developer Mode in Settings > Apps > Advanced settings.

To add Plain's MCP as an app:

1. Go to Settings > Apps

2. Click Create app to add a new connector

3. Name it "Plain" and enter the URL https://mcp.plain.com/mcp

4. Set authentication to OAuth, then click Create and complete the login flow.

Cursor

You can add the Plain MCP to Cursor via your Cursor config at ~/.cursor/mcp.json

{
  "mcpServers": {
    "plain": {
      "type": "remote",
      "url": "https://mcp.plain.com/mcp"
    }
  }
}

Go to Cursor Settings > Tools & MCP and click Connect next to Plain to authenticate.

Claude.ai

1. Navigate to "Customize" → "Connectors"

2. Click the ➕ icon, then choose "Add custom connector"

3. Add a custom connector named "Plain" with the Remote MCP server URL https://mcp.plain.com/mcp

4. Click the "Connect" button next to the newly created Plain connector to authenticate.

Claude Code

Adding the Plain MCP to claude-code can be done via the mcp-remote helper package which involves adding the following to your ~/.claude.json configuration.

"mcpServers": {
  "plain": {
    "command": "npx",
    "args": ["-y", "mcp-remote", "https://mcp.plain.com/mcp"],
    "enabled": true
  }
}

Next time you start Claude Code, it will launch a browser window asking you to authenticate with your Plain account and select the workspace you'd like to connect. Run the /mcp command and select the plain MCP to see more details.

Other MCP Clients

MCP clients that run locally (not in the browser) can connect to Plain if they support remote HTTP servers. Point it at https://mcp.plain.com/mcp and complete the OAuth flow when prompted.

Authentication

Plain MCP uses OAuth to allow your MCP server connection to share the same context as your normal web app user. No additional managing of permissions required. This means replies to threads will appear as though they come from your user.

After successfully authenticating, your client should receive both an accessToken as well as a refreshToken. It is the client's responsibility to do the actual refreshing. Most agentic coding applications support this now, but we have had issues with claude-code in particular. That is why we recommend using the 'mcp-remote' package and setup detailed above, instead of passing only the URL as a "remote" mcp server in claude's configuration.

Available tools

The MCP server includes 30 tools. Tools marked write take actions in your workspace. Most AI clients will ask for confirmation before executing them.

Threads

Customers

Tenants

Help center

User and workspace

Use case examples

Triage your queue

"Show me my assigned threads. Summarize the top 5 by urgency and suggest which ones I should handle first."

Read your active threads and get a prioritized summary without opening each one.

Understand a customer's history

"Look up the customer with email alex@acme.com. Show me their recent threads and summarize the pattern. Are they hitting the same issue repeatedly?"

Pull together a customer's full context in seconds instead of clicking through timelines.

Summarize what's waiting

"Show me all my TODO threads. Group them by label and summarize what each one is about."

Get a quick view of what's gone quiet so you can decide what needs attention.

Draft a reply with full context

"Show me thread th_01ABC123. Read the full timeline, then draft a reply that addresses the customer's latest question. Use a helpful but concise tone."

The AI reads the full thread history and drafts a reply for you to review before sending.

Audit your help center

"List all articles in my help center. Flag any that haven't been updated in the last 90 days."

Spot outdated documentation without manually checking each article.

Get a snapshot of a tenant's health

"Look up the tenant 'Acme Corp'. Show me their details and all open threads. Are there any patterns or escalation risks?"

Prep for an account review by pulling tenant context and open issues together.

Cross-reference with other tools

The Plain MCP works alongside other MCP servers. If you also have Slack, GitHub, or Linear MCPs connected, you can combine them:

"Find threads about 'payment errors' from the last 7 days, check if there's a related GitHub issue, and post a summary to #incidents in Slack."

Each server handles its own domain, and the AI coordinates between them.

If something isn't working

• Can't authenticate: Make sure you can log into Plain at app.plain.com first. The MCP server uses the same auth.

• Tool not appearing: Some AI clients cache available tools. Try disconnecting and reconnecting the MCP server.

• Permission errors: Check that your Plain user has the right role for the action you're trying to take.

If it's still not working, collect:

• Your workspace ID (visible in Settings > Workspace)

• The exact error message

• Which AI client you're using

Then reach out to us via help@plain.com for assistance.