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. You authenticate with your existing Plain account, so the MCP server has the same permissions as your user. No API keys needed.

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:

Go to Settings → Apps
Click Create app, Name it “Plain” and enter the URL https://mcp.plain.com/mcp
Set authentication to OAuth, then click Create and complete the login flow.

If you don’t see “Advanced Settings” in the “Apps” settings menu, you might need to reach out to your administrator to enable adding “Custom Apps” for your team.

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

Go to “Customize” → “Connectors”
Click the ➕ icon, then choose “Add custom connector”
Add a custom connector named “Plain” with the Remote MCP server URL https://mcp.plain.com/mcp
Click the “Connect” button next to the newly created Plain connector to authenticate.

If you’re on a Claude Team plan, you may need to reach out to your administrator to add this custom connector for you.

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
  }
}

Unfortunately Claude Code does not support refreshing OAuth tokens yet. A workaround until that is implemented is to use the mcp-remote npm package. 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. Use the ‘mcp-remote’ package and the setup detailed above rather than 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

Tool	Access	What it does
Fetch Threads	Read	List threads with filters and pagination
Fetch Thread Details	Read	Full thread details plus timeline entries
Fetch My Assigned Threads	Read	List threads assigned to you (active by default)
Search Threads	Read	Search threads by text with optional filters
Reply To Thread	Write	Send a reply to an email, Slack, or form thread
Assign Thread	Write	Assign a thread to a user, machine user, or yourself
Unassign Thread	Write	Remove the current assignee
Mark Thread As Done	Write	Mark a thread as resolved
Mark Thread As Todo	Write	Reopen or set a thread back to active
Snooze Thread	Write	Snooze a thread until later
Change Thread Priority	Write	Set priority: urgent, high, normal, or low
Add Labels	Write	Add labels to a thread
Create Note	Write	Add an internal note to a thread or customer
Fetch Citations	Read	List knowledge sources that Ari used when replying on a thread

Customers

Tool	Access	What it does
Fetch Customers	Read	List customers (excludes spam by default)
Fetch Customer Details	Read	Full profile for a specific customer
Fetch Customer Threads	Read	List threads for a specific customer
Search Customers	Read	Search by name, email, or external ID

Tenants

Tool	Access	What it does
Fetch Tenants	Read	List tenants with pagination
Fetch Tenant Details	Read	Full details including tenant fields
Search Tenants	Read	Search by name or external ID
Upsert Tenant	Write	Create or update a tenant

Help Center

Tool	Access	What it does
Get Help Centers	Read	List your help centers
Get Help Center Article Groups	Read	List your Help Center article groups
Get Help Center Articles	Read	List articles in a Help Center
Get Help Center Article	Read	Fetch an article by ID
Get Help Center Article By Slug	Read	Fetch an article by slug
Upsert Help Center Article	Write	Create or update an article

User and workspace

Tool	Access	What it does
Fetch My User	Read	Your authenticated user profile
Fetch My Workspace	Read	Your workspace details
Fetch User By Email	Read	Find a Plain user by email address
Fetch Labels	Read	List all labels in your 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.”

See what has 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.

GraphQL API

Building Agents

Webhooks

Channels

Customer Cards

UI Components

Security

Changelog

Setup

ChatGPT

Cursor

Claude.ai

Claude Code

Other MCP clients

Authentication

Available tools

Threads

Customers

Tenants

Help Center

User and workspace

Use case examples

Triage your queue

Understand a customer’s history

Summarize what’s waiting

Draft a reply with full context

Audit your Help Center

Get a snapshot of a tenant’s health

Cross-reference with other tools

If something isn’t working

​Setup

​ChatGPT

​Cursor

​Claude.ai

​Claude Code

​Other MCP clients

​Authentication

​Available tools

​Threads

​Customers

​Tenants

​Help Center

​User and workspace

​Use case examples

​Triage your queue

​Understand a customer’s history

​Summarize what’s waiting

​Draft a reply with full context

​Audit your Help Center

​Get a snapshot of a tenant’s health

​Cross-reference with other tools

​If something isn’t working

Setup

ChatGPT

Cursor

Claude.ai

Claude Code

Other MCP clients

Authentication

Available tools

Threads

Customers

Tenants

Help Center

User and workspace

Use case examples

Triage your queue

Understand a customer’s history

Summarize what’s waiting

Draft a reply with full context

Audit your Help Center

Get a snapshot of a tenant’s health

Cross-reference with other tools

If something isn’t working