# How to integrate Signpath MCP with Pydantic AI ```json { "title": "How to integrate Signpath MCP with Pydantic AI", "toolkit": "Signpath", "toolkit_slug": "signpath", "framework": "Pydantic AI", "framework_slug": "pydantic-ai", "url": "https://composio.dev/toolkits/signpath/framework/pydantic-ai", "markdown_url": "https://composio.dev/toolkits/signpath/framework/pydantic-ai.md", "updated_at": "2026-05-12T10:26:12.005Z" } ``` ## Introduction This guide walks you through connecting Signpath to Pydantic AI using the Composio tool router. By the end, you'll have a working Signpath agent that can list all available code signing certificates, show all projects for your organization, get details of current signing policies through natural language commands. This guide will help you understand how to give your Pydantic AI agent real control over a Signpath account through Composio's Signpath MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved. ## Also integrate Signpath with - [OpenAI Agents SDK](https://composio.dev/toolkits/signpath/framework/open-ai-agents-sdk) - [Claude Agent SDK](https://composio.dev/toolkits/signpath/framework/claude-agents-sdk) - [Claude Code](https://composio.dev/toolkits/signpath/framework/claude-code) - [Claude Cowork](https://composio.dev/toolkits/signpath/framework/claude-cowork) - [Codex](https://composio.dev/toolkits/signpath/framework/codex) - [OpenClaw](https://composio.dev/toolkits/signpath/framework/openclaw) - [Hermes](https://composio.dev/toolkits/signpath/framework/hermes-agent) - [CLI](https://composio.dev/toolkits/signpath/framework/cli) - [Google ADK](https://composio.dev/toolkits/signpath/framework/google-adk) - [LangChain](https://composio.dev/toolkits/signpath/framework/langchain) - [Vercel AI SDK](https://composio.dev/toolkits/signpath/framework/ai-sdk) - [Mastra AI](https://composio.dev/toolkits/signpath/framework/mastra-ai) - [LlamaIndex](https://composio.dev/toolkits/signpath/framework/llama-index) - [CrewAI](https://composio.dev/toolkits/signpath/framework/crew-ai) ## 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 Signpath - 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 Signpath 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 Signpath MCP server, and what's possible with it? The Signpath MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Signpath account. It provides structured and secure access to your code signing workflows, so your agent can list certificates, retrieve project details, access signing policies, and check system metadata automatically on your behalf. - Certificate management and discovery: Quickly list all available code signing certificates within your organization, making it easy for your agent to select the right certificate for each workflow. - Automated project listing and tracking: Let your agent fetch and paginate through all Signpath projects, helping you organize, monitor, and automate signing across multiple software projects. - Signing policy insights and selection: Effortlessly retrieve detailed information about your organization’s signing policies, so your agent can ensure every artifact is signed according to security best practices. - System information and environment awareness: Instantly access Signpath system details, including product info, API version, and environment metadata, to keep your agent up to date with the latest platform capabilities. ## Supported Tools | Tool slug | Name | Description | |---|---|---| | `SIGNPATH_GET_HEALTH_CHECK` | Get Health Check | Tool to check if the SignPath API is healthy and operational. Use this to verify API availability before performing other operations. | | `SIGNPATH_LIST_CERTIFICATES` | List Certificates | Retrieve all certificates available in a SignPath organization. Use this to discover certificate IDs needed for signing operations. Requires a valid organization_id which can be obtained from your SignPath account settings. | | `SIGNPATH_LIST_PROJECTS` | List Projects | Tool to list all projects for an organization. Use after confirming the organization ID to retrieve and paginate project records. | | `SIGNPATH_RETRIEVE_SIGNING_POLICY_DETAILS` | Retrieve Signing Policy Details | Retrieve signing policy details for code signing operations. Returns certificate info, RSA key parameters, and policy metadata for the authenticated user's accessible signing policies. Without filters, returns all policies where the user is assigned as Submitter. | | `SIGNPATH_RETRIEVE_SYSTEM_INFO` | Retrieve System Info | Retrieves SignPath system information including the application version and the web UI base URL. Use this tool to verify the SignPath installation version or to obtain the web interface URL. | ## Supported Triggers None listed. ## Creating MCP Server - Stand-alone vs Composio SDK The Signpath MCP server is an implementation of the Model Context Protocol that connects your AI agent to Signpath. It provides structured and secure access so your agent can perform Signpath operations on your behalf through a secure, permission-based interface. With Composio's managed implementation, you don't have to create your own developer app. For production, if you're building an end product, we recommend using your own credentials. The managed server helps you prototype fast and go from 0-1 faster. ## Step-by-step Guide ### 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 ### 1. Getting API Keys for OpenAI and Composio OpenAI API Key - Go to the [OpenAI dashboard](https://platform.openai.com/settings/organization/api-keys) 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](https://dashboard.composio.dev?utm_source=toolkits&utm_medium=framework_docs). - Navigate to your API settings and generate a new API key. - Store this key securely as you'll need it for authentication. ### 2. Install dependencies Install the required libraries. What's happening: - composio connects your agent to external SaaS tools like Signpath - pydantic-ai lets you create structured AI agents with tool support - python-dotenv loads your environment variables securely from a .env file ```bash pip install composio pydantic-ai python-dotenv ``` ### 3. Set up environment variables 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 ```bash COMPOSIO_API_KEY=your_composio_api_key_here USER_ID=your_user_id_here OPENAI_API_KEY=your_openai_api_key ``` ### 4. Import dependencies What's happening: - We load environment variables and import required modules - Composio manages connections to Signpath - MCPServerStreamableHTTP connects to the Signpath MCP server endpoint - Agent from Pydantic AI lets you define and run the AI assistant ```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() ``` ### 5. Create a Tool Router Session What's happening: - We're creating a Tool Router session that gives your agent access to Signpath 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 ```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 Signpath composio = Composio(api_key=api_key) session = composio.create( user_id=user_id, toolkits=["signpath"], ) url = session.mcp.url if not url: raise ValueError("Composio session did not return an MCP URL") ``` ### 6. Initialize the Pydantic AI Agent What's happening: - The MCP client connects to the Signpath endpoint - The agent uses GPT-5 to interpret user commands and perform Signpath operations - The instructions field defines the agent's role and behavior ```python # Attach the MCP server to a Pydantic AI Agent signpath_mcp = MCPServerStreamableHTTP(url, headers={"x-api-key": COMPOSIO_API_KEY}) agent = Agent( "openai:gpt-5", toolsets=[signpath_mcp], instructions=( "You are a Signpath assistant. Use Signpath tools to help users " "with their requests. Ask clarifying questions when needed." ), ) ``` ### 7. Build the chat interface What's happening: - The agent reads input from the terminal and streams its response - Signpath API calls happen automatically under the hood - The model keeps conversation history to maintain context across turns ```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 Signpath.\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() ``` ### 8. Run the application What's happening: - The asyncio loop launches the agent and keeps it running until you exit ```python if __name__ == "__main__": asyncio.run(main()) ``` ## Complete Code ```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 Signpath composio = Composio(api_key=api_key) session = composio.create( user_id=user_id, toolkits=["signpath"], ) 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 signpath_mcp = MCPServerStreamableHTTP(url, headers={"x-api-key": COMPOSIO_API_KEY}) agent = Agent( "openai:gpt-5", toolsets=[signpath_mcp], instructions=( "You are a Signpath assistant. Use Signpath 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 Signpath.\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 Signpath through Composio's Tool Router. With this setup, your agent can perform real Signpath 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 + Signpath for workflow automation) This architecture makes your AI agent "agent-native", able to securely use APIs in a unified, composable way without custom integrations. ## How to build Signpath MCP Agent with another framework - [OpenAI Agents SDK](https://composio.dev/toolkits/signpath/framework/open-ai-agents-sdk) - [Claude Agent SDK](https://composio.dev/toolkits/signpath/framework/claude-agents-sdk) - [Claude Code](https://composio.dev/toolkits/signpath/framework/claude-code) - [Claude Cowork](https://composio.dev/toolkits/signpath/framework/claude-cowork) - [Codex](https://composio.dev/toolkits/signpath/framework/codex) - [OpenClaw](https://composio.dev/toolkits/signpath/framework/openclaw) - [Hermes](https://composio.dev/toolkits/signpath/framework/hermes-agent) - [CLI](https://composio.dev/toolkits/signpath/framework/cli) - [Google ADK](https://composio.dev/toolkits/signpath/framework/google-adk) - [LangChain](https://composio.dev/toolkits/signpath/framework/langchain) - [Vercel AI SDK](https://composio.dev/toolkits/signpath/framework/ai-sdk) - [Mastra AI](https://composio.dev/toolkits/signpath/framework/mastra-ai) - [LlamaIndex](https://composio.dev/toolkits/signpath/framework/llama-index) - [CrewAI](https://composio.dev/toolkits/signpath/framework/crew-ai) ## Related Toolkits - [Supabase](https://composio.dev/toolkits/supabase) - Supabase is an open-source backend platform offering scalable Postgres databases, authentication, storage, and real-time APIs. It lets developers build modern apps without managing infrastructure. - [Codeinterpreter](https://composio.dev/toolkits/codeinterpreter) - Codeinterpreter is a Python-based coding environment with built-in data analysis and visualization. It lets you instantly run scripts, plot results, and prototype solutions inside supported platforms. - [GitHub](https://composio.dev/toolkits/github) - GitHub is a code hosting platform for version control and collaborative software development. It streamlines project management, code review, and team workflows in one place. - [Ably](https://composio.dev/toolkits/ably) - Ably is a real-time messaging platform for live chat and data sync in modern apps. It offers global scale and rock-solid reliability for seamless, instant experiences. - [Abuselpdb](https://composio.dev/toolkits/abuselpdb) - Abuselpdb is a central database for reporting and checking IPs linked to malicious online activity. Use it to quickly identify and report suspicious or abusive IP addresses. - [Alchemy](https://composio.dev/toolkits/alchemy) - Alchemy is a blockchain development platform offering APIs and tools for Ethereum apps. It simplifies building and scaling Web3 projects with robust infrastructure. - [Algolia](https://composio.dev/toolkits/algolia) - Algolia is a hosted search API that powers lightning-fast, relevant search experiences for web and mobile apps. It helps developers deliver instant, typo-tolerant, and scalable search without complex infrastructure. - [Anchor browser](https://composio.dev/toolkits/anchor_browser) - Anchor browser is a developer platform for AI-powered web automation. It transforms complex browser actions into easy API endpoints for streamlined web interaction. - [Apiflash](https://composio.dev/toolkits/apiflash) - Apiflash is a website screenshot API for programmatically capturing web pages. It delivers high-quality screenshots on demand for automation, monitoring, or reporting. - [Apiverve](https://composio.dev/toolkits/apiverve) - Apiverve delivers a suite of powerful APIs that simplify integration for developers. It's designed for reliability and scalability so you can build faster, smarter applications without the integration headache. - [Appcircle](https://composio.dev/toolkits/appcircle) - Appcircle is an enterprise-grade mobile CI/CD platform for building, testing, and publishing mobile apps. It streamlines mobile DevOps so teams ship faster and with more confidence. - [Appdrag](https://composio.dev/toolkits/appdrag) - Appdrag is a cloud platform for building websites, APIs, and databases with drag-and-drop tools and code editing. It accelerates development and iteration by combining hosting, database management, and low-code features in one place. - [Appveyor](https://composio.dev/toolkits/appveyor) - AppVeyor is a cloud-based continuous integration service for building, testing, and deploying applications. It helps developers automate and streamline their software delivery pipelines. - [Backendless](https://composio.dev/toolkits/backendless) - Backendless is a backend-as-a-service platform for mobile and web apps, offering database, file storage, user authentication, and APIs. It helps developers ship scalable applications faster without managing server infrastructure. - [Baserow](https://composio.dev/toolkits/baserow) - Baserow is an open-source no-code database platform for building collaborative data apps. It makes it easy for teams to organize data and automate workflows without writing code. - [Bench](https://composio.dev/toolkits/bench) - Bench is a benchmarking tool for automated performance measurement and analysis. It helps you quickly evaluate, compare, and track your systems or workflows. - [Better stack](https://composio.dev/toolkits/better_stack) - Better Stack is a monitoring, logging, and incident management solution for apps and services. It helps teams ensure application reliability and performance with real-time insights. - [Bitbucket](https://composio.dev/toolkits/bitbucket) - Bitbucket is a Git-based code hosting and collaboration platform for teams. It enables secure repository management and streamlined code reviews. - [Blazemeter](https://composio.dev/toolkits/blazemeter) - Blazemeter is a continuous testing platform for web and mobile app performance. It empowers teams to automate and analyze large-scale tests with ease. - [Blocknative](https://composio.dev/toolkits/blocknative) - Blocknative delivers real-time mempool monitoring and transaction management for public blockchains. Instantly track pending transactions and optimize blockchain interactions with live data. ## Frequently Asked Questions ### What are the differences in Tool Router MCP and Signpath MCP? With a standalone Signpath MCP server, the agents and LLMs can only access a fixed set of Signpath tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Signpath and many other apps based on the task at hand, all through a single MCP endpoint. ### Can I use Tool Router MCP with Pydantic AI? 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 Signpath tools. ### Can I manage the permissions and scopes for Signpath while using Tool Router? Yes, absolutely. You can configure which Signpath 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 Signpath data and credentials are handled as safely as possible. --- [See all toolkits](https://composio.dev/toolkits) · [Composio docs](https://docs.composio.dev/llms.txt)