How to connect Postgrid to Claude Cowork

Trusted by teams atAWSGleanZoomAirtable

30 min · no commitment · see it on your stack

Postgrid logo
Claude Cowork logo
divider

Introduction

Cowork is Anthropic's AI agent for knowledge work. Think of it as Claude Code for everything else. It works autonomously with your computer, local files, and applications to accomplish complex tasks.

This guide walks you through the easiest and most secure way to connect your Postgrid account to Cowork via Composio Connect, enabling it to send a letter to new customer address, verify and standardize a shipping address, create a reusable postcard template, and more such actions on your behalf without compromising your account security.

Also integrate Postgrid with

Connecting Postgrid to Claude Cowork

1. Open Customize

In Claude Desktop, click Customize in the left sidebar, then select Connectors and click the + icon at the top.

Claude Desktop connectors screen with Add custom connector selected

2. Add the Composio MCP server

Click Add custom connector and paste in the Composio MCP server URL:

bash
https://connect.composio.dev/mcp
Add custom connector dialog with Composio MCP server URL

3. Authorize in your browser

Click Connect. You'll be redirected to a browser window where you can authorize Composio to continue.

Composio authorization screen for Claude Cowork

4. Connect your Postgrid account

Back in Cowork, ask the agent to connect to Postgrid or give it any Postgrid-related task.

For example, ask Cowork to:

  • "Send a letter to new customer address"
  • "Verify and standardize a shipping address"
  • "Create a reusable postcard template"

It will prompt you to authenticate and authorize access.

That's it. Composio's tools are now available in Cowork, and your Postgrid account is ready to use.

What is Claude Cowork?

Claude Cowork is Anthropic's agent for general knowledge work. It can use your computer, files, and connected applications to complete longer-running tasks across your work tools.

With Composio Connect, Cowork can securely access apps like Postgrid through MCP without you sharing account credentials directly with the agent.

What is the Postgrid MCP server, and what's possible with it?

The Postgrid MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Postgrid account. It provides structured and secure access to your direct mail and address automation tools, so your agent can verify addresses, send letters, manage contacts, and handle templates for your business communications—all without manual intervention.

  • Automated letter sending: Have your agent create and send physical letters on demand, handling recipient, sender, and content details seamlessly.
  • Contact management: Effortlessly add, update, or delete contacts in your Postgrid account to keep your mailing lists accurate and up to date.
  • Template creation and maintenance: Let your agent generate reusable mail templates with dynamic placeholders, and remove outdated templates as needed.
  • Bank account and payment management: Create or delete bank accounts associated with print and mail services, ensuring smooth financial operations for mail automation.
  • Webhook setup and monitoring: Enable your agent to create or remove webhooks to track events and receive real-time notifications for your mail orders and services.

Supported Tools & Triggers

Tools
CREATE_BANK_ACCOUNTTool to create a new bank account for print & mail service.
Create ContactTool to create a new contact in postgrid.
Create LetterTool to create and send a letter via postgrid.
Create TemplateTool to create a new mail template in postgrid.
Create WebhookTool to create a new webhook to receive order event notifications.
Delete Bank AccountTool to delete a bank account by its id.
Delete ContactTool to delete a contact by its id.
Delete TemplateTool to delete a template by its id.
Delete WebhookTool to delete a webhook subscription.
Get Bank AccountTool to retrieve a bank account.
Get ContactTool to retrieve a contact.
Get LetterTool to retrieve a letter.
Get TemplateTool to retrieve a template.
Get WebhookTool to retrieve details of a specific webhook by its id.
List Bank AccountsTool to list bank accounts.
List ChequesTool to list cheques with optional filters and pagination.
List ContactsTool to list contacts.
List LettersTool to list letters.
List PostcardsTool to retrieve a list of postcards with optional filtering and pagination.
List Self-MailersTool to list self-mailers.
List TemplatesTool to list templates.
List WebhooksTool to retrieve a list of configured webhooks with optional filtering and pagination.

How to build Postgrid MCP Agent with another framework

FAQ

What are the differences in Tool Router MCP and Postgrid MCP?

With a standalone Postgrid MCP server, the agents and LLMs can only access a fixed set of Postgrid tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Postgrid and many other apps based on the task at hand, all through a single MCP endpoint.

Can I use Tool Router MCP with Claude Cowork?

Yes, you can. Claude Cowork fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Postgrid tools.

Can I manage the permissions and scopes for Postgrid while using Tool Router?

Yes, absolutely. You can configure which Postgrid scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do.

How safe is my data with Composio Tool Router?

All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Postgrid data and credentials are handled as safely as possible.

Used by agents from

Context
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai
Context
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai
Context
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai

Never worry about agent reliability

We handle tool reliability, observability, and security so you never have to second-guess an agent action.