Lob MCP Server for Pydantic AIGive Pydantic AI instant access to 9 tools to Autocomplete Address, Create Check, Create Letter, and more
Pydantic AI brings type-safe agent development to Python with first-class MCP support. Connect Lob through Vinkius and every tool is automatically validated against Pydantic schemas. catch errors at build time, not in production.
Ask AI about this App Connector for Pydantic AI
The Lob app connector for Pydantic AI is a standout in the Marketing Automation category — giving your AI agent 9 tools to work with, ready to go from day one.
Vinkius delivers Streamable HTTP and SSE to any MCP client
import asyncio
from pydantic_ai import Agent
from pydantic_ai.mcp import MCPServerHTTP
async def main():
# Your Vinkius token. get it at cloud.vinkius.com
server = MCPServerHTTP(url="https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp")
agent = Agent(
model="openai:gpt-4o",
mcp_servers=[server],
system_prompt=(
"You are an assistant with access to Lob "
"(9 tools)."
),
)
result = await agent.run(
"What tools are available in Lob?"
)
print(result.data)
asyncio.run(main())
* Every MCP server runs on Vinkius-managed infrastructure inside AWS - a purpose-built runtime with per-request V8 isolates, Ed25519 signed audit chains, and sub-40ms cold starts optimized for native MCP execution. See our infrastructure
About Lob MCP Server
Connect your Lob account to any AI agent and manage direct mail through natural conversation.
Pydantic AI validates every Lob tool response against typed schemas, catching data inconsistencies at build time. Connect 9 tools through Vinkius and switch between OpenAI, Anthropic, or Gemini without changing your integration code. full type safety, structured output guarantees, and dependency injection for testable agents.
What you can do
- Letter Sending — Create and send letters with PDF or HTML content
- Postcard Campaigns — Send postcards with front/back designs
- Check Printing — Create and mail checks with payment details
- Address Verification — Verify and standardize US addresses
- Template Management — Browse and manage mail templates
- Delivery Tracking — Track mail pieces through the postal system
The Lob MCP Server exposes 9 tools through the Vinkius. Connect it to Pydantic AI in under two minutes — no API keys to rotate, no infrastructure to provision, no vendor lock-in. Your configuration, your data, your control.
All 9 Lob tools available for Pydantic AI
When Pydantic AI connects to Lob through Vinkius, your AI agent gets direct access to every tool listed below — spanning direct-mail, address-verification, print-automation, and more. Every call is secured with network, filesystem, subprocess, and code evaluation entitlements inside a sandboxed runtime. Beyond a simple connection, you get a full AI Gateway with real-time visibility into agent activity, enterprise governance, and optimized token usage.
Suggest address completions
Send a physical check
Supports certified mail and custom inserts. Send a physical letter
Supports HTML or PDF for front and back. Send a physical postcard
Track a mail piece
List sent letters
List sent postcards
Verify an international address
Verify a US address
Connect Lob to Pydantic AI via MCP
Follow these steps to wire Lob into Pydantic AI. The entire setup takes under two minutes — your credentials stay safe behind the Vinkius.
Install Pydantic AI
pip install pydantic-aiReplace the token
[YOUR_TOKEN_HERE] with your Vinkius tokenRun the agent
agent.py and run: python agent.pyExplore tools
Why Use Pydantic AI with the Lob MCP Server
Pydantic AI provides unique advantages when paired with Lob through the Model Context Protocol.
Full type safety: every MCP tool response is validated against Pydantic models, catching data inconsistencies before they reach your application
Model-agnostic architecture. switch between OpenAI, Anthropic, or Gemini without changing your Lob integration code
Structured output guarantee: Pydantic AI ensures tool results conform to defined schemas, eliminating runtime type errors
Dependency injection system cleanly separates your Lob connection logic from agent behavior for testable, maintainable code
Lob + Pydantic AI Use Cases
Practical scenarios where Pydantic AI combined with the Lob MCP Server delivers measurable value.
Type-safe data pipelines: query Lob with guaranteed response schemas, feeding validated data into downstream processing
API orchestration: chain multiple Lob tool calls with Pydantic validation at each step to ensure data integrity end-to-end
Production monitoring: build validated alert agents that query Lob and output structured, schema-compliant notifications
Testing and QA: use Pydantic AI's dependency injection to mock Lob responses and write comprehensive agent tests
Example Prompts for Lob in Pydantic AI
Ready-to-use prompts you can give your Pydantic AI agent to start working with Lob immediately.
"Send a welcome letter to a new customer and verify their address first."
"Show all mail pieces sent this month with delivery status."
"Create a check for $5,000 and browse mail templates."
Troubleshooting Lob MCP Server with Pydantic AI
Common issues when connecting Lob to Pydantic AI through the Vinkius, and how to resolve them.
MCPServerHTTP not found
pip install --upgrade pydantic-aiLob + Pydantic AI FAQ
Common questions about integrating Lob MCP Server with Pydantic AI.
How does Pydantic AI discover MCP tools?
MCPServerHTTP instance with the server URL. Pydantic AI connects, discovers all tools, and generates typed Python interfaces automatically.