How to integrate Kapso MCP with Pydantic AI

This guide walks you through connecting Kapso to Pydantic AI using the Composio tool router. By the end, you'll have a working Kapso agent that can list your conversations, read messages, view customers, check phone health, and review workflows through natural language commands. This guide will help you understand how to give your Pydantic AI agent real control over a Kapso account through Composio's Kapso MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

Kapso logoKapso
Api Key

Kapso is an API platform for WhatsApp messaging, contacts, broadcasts, workflows, and serverless functions. It helps teams manage customer conversations and automate outreach from one place.

10 Tools

Introduction

This guide walks you through connecting Kapso to Pydantic AI using the Composio tool router. By the end, you'll have a working Kapso agent that can list your conversations, read messages, view customers, check phone health, and review workflows through natural language commands.

This guide will help you understand how to give your Pydantic AI agent real control over a Kapso account through Composio's Kapso MCP server.

Before we dive in, let's take a quick look at the key ideas and tools involved.

Also integrate Kapso with

TL;DR

Here's what you'll learn:
  • How to set up your Composio API key and User ID
  • How to create a Composio Tool Router session for Kapso
  • How to attach an MCP Server to a Pydantic AI agent
  • How to stream responses and maintain chat history
  • How to build a simple REPL-style chat interface to test your Kapso workflows

What is Pydantic AI?

Pydantic AI is a Python framework for building AI agents with strong typing and validation. It leverages Pydantic's data validation capabilities to create robust, type-safe AI applications.

Key features include:

  • Type Safety: Built on Pydantic for automatic data validation
  • MCP Support: Native support for Model Context Protocol servers
  • Streaming: Built-in support for streaming responses
  • Async First: Designed for async/await patterns

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

The Kapso MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Kapso account. It provides structured and secure access to your WhatsApp conversations, messages, customers, phone numbers, workflows, and serverless functions, so your agent can review conversations, inspect message history, find customers, check phone number health, and examine automations on your behalf.

  • Conversation and message review: Have your agent list recent WhatsApp conversations, filter them by status or assignment, and inspect message history.
  • Customer lookup: Let the agent find Kapso customers by name, external reference, or creation date.
  • Phone number monitoring: Direct your agent to review configured WhatsApp phone numbers and check their current health, messaging state, and configuration.
  • Workflow inspection: Instruct your agent to list workflows, filter them by name or lifecycle status, and examine their definitions and available variables.
  • Serverless function visibility: Have your agent list Kapso functions and inspect their code, runtime settings, deployment status, and computed URLs without running or changing them.

What is the Composio tool router, and how does it fit here?

What is Composio SDK?

Composio's Composio SDK helps agents find the right tools for a task at runtime. You can plug in multiple toolkits (like Gmail, HubSpot, and GitHub), and the agent will identify the relevant app and action to complete multi-step workflows. This can reduce token usage and improve the reliability of tool calls. Read more here: Getting started with Composio SDK

The tool router generates a secure MCP URL that your agents can access to perform actions.

How the Composio SDK works

The Composio SDK follows a three-phase workflow:

  1. Discovery: Searches for tools matching your task and returns relevant toolkits with their details.
  2. Authentication: Checks for active connections. If missing, creates an auth config and returns a connection URL via Auth Link.
  3. Execution: Executes the action using the authenticated connection.

Step-by-step Guide

Step by step09 STEPS
1

Prerequisites

Before starting, make sure you have:
  • Python 3.9 or higher
  • A Composio account with an active API key
  • Basic familiarity with Python and async programming
2

Getting API Keys for OpenAI and Composio

OpenAI API Key
  • Go to the OpenAI dashboard and create an API key. You'll need credits to use the models, or you can connect to another model provider.
  • Keep the API key safe.
Composio API Key
  • Log in to the Composio dashboard.
  • Navigate to your API settings and generate a new API key.
  • Store this key securely as you'll need it for authentication.
3

Install dependencies

bash
pip install composio pydantic-ai python-dotenv

Install the required libraries.

What's happening:

  • composio connects your agent to external SaaS tools like Kapso
  • pydantic-ai lets you create structured AI agents with tool support
  • python-dotenv loads your environment variables securely from a .env file
4

Set up environment variables

bash
COMPOSIO_API_KEY=your_composio_api_key_here
USER_ID=your_user_id_here
OPENAI_API_KEY=your_openai_api_key

Create a .env file in your project root.

What's happening:

  • COMPOSIO_API_KEY authenticates your agent to Composio's API
  • USER_ID associates your session with your account for secure tool access
  • OPENAI_API_KEY to access OpenAI LLMs
5

Import dependencies

python
import asyncio
import os
from dotenv import load_dotenv
from composio import Composio
from pydantic_ai import Agent
from pydantic_ai.mcp import MCPServerStreamableHTTP

load_dotenv()
What's happening:
  • We load environment variables and import required modules
  • Composio manages connections to Kapso
  • MCPServerStreamableHTTP connects to the Kapso MCP server endpoint
  • Agent from Pydantic AI lets you define and run the AI assistant
6

Create a Tool Router Session

python
async def main():
    api_key = os.getenv("COMPOSIO_API_KEY")
    user_id = os.getenv("USER_ID")
    if not api_key or not user_id:
        raise RuntimeError("Set COMPOSIO_API_KEY and USER_ID in your environment")

    # Create a Composio Tool Router session for Kapso
    composio = Composio(api_key=api_key)
    session = composio.create(
        user_id=user_id,
        toolkits=["kapso"],
    )
    url = session.mcp.url
    if not url:
        raise ValueError("Composio session did not return an MCP URL")
What's happening:
  • We're creating a Tool Router session that gives your agent access to Kapso tools
  • The create method takes the user ID and specifies which toolkits should be available
  • The returned session.mcp.url is the MCP server URL that your agent will use
7

Initialize the Pydantic AI Agent

python
# Attach the MCP server to a Pydantic AI Agent
kapso_mcp = MCPServerStreamableHTTP(url, headers={"x-api-key": COMPOSIO_API_KEY})
agent = Agent(
    "openai:gpt-5",
    toolsets=[kapso_mcp],
    instructions=(
        "You are a Kapso assistant. Use Kapso tools to help users "
        "with their requests. Ask clarifying questions when needed."
    ),
)
What's happening:
  • The MCP client connects to the Kapso endpoint
  • The agent uses GPT-5 to interpret user commands and perform Kapso operations
  • The instructions field defines the agent's role and behavior
8

Build the chat interface

python
# Simple REPL with message history
history = []
print("Chat started! Type 'exit' or 'quit' to end.\n")
print("Try asking the agent to help you with Kapso.\n")

while True:
    user_input = input("You: ").strip()
    if user_input.lower() in {"exit", "quit", "bye"}:
        print("\nGoodbye!")
        break
    if not user_input:
        continue

    print("\nAgent is thinking...\n", flush=True)

    async with agent.run_stream(user_input, message_history=history) as stream_result:
        collected_text = ""
        async for chunk in stream_result.stream_output():
            text_piece = None
            if isinstance(chunk, str):
                text_piece = chunk
            elif hasattr(chunk, "delta") and isinstance(chunk.delta, str):
                text_piece = chunk.delta
            elif hasattr(chunk, "text"):
                text_piece = chunk.text
            if text_piece:
                collected_text += text_piece
        result = stream_result

    print(f"Agent: {collected_text}\n")
    history = result.all_messages()
What's happening:
  • The agent reads input from the terminal and streams its response
  • Kapso API calls happen automatically under the hood
  • The model keeps conversation history to maintain context across turns
9

Run the application

python
if __name__ == "__main__":
    asyncio.run(main())
What's happening:
  • The asyncio loop launches the agent and keeps it running until you exit

Complete Code

Here's the complete code to get you started with Kapso and Pydantic AI:

python
import asyncio
import os
from dotenv import load_dotenv
from composio import Composio
from pydantic_ai import Agent
from pydantic_ai.mcp import MCPServerStreamableHTTP

load_dotenv()

async def main():
    api_key = os.getenv("COMPOSIO_API_KEY")
    user_id = os.getenv("USER_ID")
    if not api_key or not user_id:
        raise RuntimeError("Set COMPOSIO_API_KEY and USER_ID in your environment")

    # Create a Composio Tool Router session for Kapso
    composio = Composio(api_key=api_key)
    session = composio.create(
        user_id=user_id,
        toolkits=["kapso"],
    )
    url = session.mcp.url
    if not url:
        raise ValueError("Composio session did not return an MCP URL")

    # Attach the MCP server to a Pydantic AI Agent
    kapso_mcp = MCPServerStreamableHTTP(url, headers={"x-api-key": COMPOSIO_API_KEY})
    agent = Agent(
        "openai:gpt-5",
        toolsets=[kapso_mcp],
        instructions=(
            "You are a Kapso assistant. Use Kapso tools to help users "
            "with their requests. Ask clarifying questions when needed."
        ),
    )

    # Simple REPL with message history
    history = []
    print("Chat started! Type 'exit' or 'quit' to end.\n")
    print("Try asking the agent to help you with Kapso.\n")

    while True:
        user_input = input("You: ").strip()
        if user_input.lower() in {"exit", "quit", "bye"}:
            print("\nGoodbye!")
            break
        if not user_input:
            continue

        print("\nAgent is thinking...\n", flush=True)

        async with agent.run_stream(user_input, message_history=history) as stream_result:
            collected_text = ""
            async for chunk in stream_result.stream_output():
                text_piece = None
                if isinstance(chunk, str):
                    text_piece = chunk
                elif hasattr(chunk, "delta") and isinstance(chunk.delta, str):
                    text_piece = chunk.delta
                elif hasattr(chunk, "text"):
                    text_piece = chunk.text
                if text_piece:
                    collected_text += text_piece
            result = stream_result

        print(f"Agent: {collected_text}\n")
        history = result.all_messages()

if __name__ == "__main__":
    asyncio.run(main())

Conclusion

You've built a Pydantic AI agent that can interact with Kapso through Composio's Tool Router. With this setup, your agent can perform real Kapso actions through natural language. You can extend this further by:
  • Adding other toolkits like Gmail, HubSpot, or Salesforce
  • Building a web-based chat interface around this agent
  • Using multiple MCP endpoints to enable cross-app workflows (for example, Gmail + Kapso for workflow automation)
This architecture makes your AI agent "agent-native", able to securely use APIs in a unified, composable way without custom integrations.
TOOLS

Supported Tools

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

Get Function

Retrieve one Kapso serverless function's code, runtime configuration, deployment status, and computed URLs without invoking or changing it.

Get Phone Number

Retrieve one Kapso WhatsApp phone-number configuration by its Meta phone number ID.

Get Phone Number Health

Run Kapso's live checks for one WhatsApp phone-number configuration and return its body-level health status and individual check results.

Get Workflow

Retrieve one workflow's metadata, full graph definition, or available variables without executing or changing it.

List Conversations

List one page of WhatsApp conversations by recent activity, with filters for phone number, status, assignment, and activity time range.

List Customers

List Kapso project customers and filter them by name, external customer ID, or creation time.

List Functions

List serverless functions configured in the Kapso project, including runtime and deployment state, without returning function source code or invoking any function.

List Messages

List one page of WhatsApp message history project-wide through Kapso Platform or for one phone number through the Meta-compatible proxy.

List Phone Numbers

List WhatsApp phone-number configurations in the Kapso project, with filters for account, customer, messaging state, and display name.

List Workflows

List project workflows and filter them by lifecycle status, name, or creation time.

FAQ

Frequently asked questions

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

Yes, you can. Pydantic AI 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 Kapso tools.

Yes, absolutely. You can configure which Kapso 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.

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 Kapso data and credentials are handled as safely as possible.

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