What types of physical mail can I send with Lob?

Lob supports three main mail types: Letters (formal correspondence, invoices, notifications with customizable color, double-sided printing), Postcards (marketing campaigns, invitations, reminders in 4x6, 6x9, or 6x11 sizes), and Checks (vendor payments, payroll, refunds, rebates with customizable memo lines and company logos). All mail is printed and mailed within 24 hours via USPS.

How does Lob address verification work?

Lob's address verification validates and standardizes addresses using USPS data. It corrects formatting, adds missing ZIP+4 codes, fixes typos, and confirms deliverability. The service returns a deliverability status: 'deliverable' (valid and deliverable), 'undeliverable' (cannot be delivered), or 'deliverable_unnecessary' (valid but additional info not needed). This reduces returned mail by up to 5% and ensures your mailings reach the correct destination.

Can I use HTML templates for personalized mailings?

Yes! Lob supports HTML templates with merge variables using the Handlebars templating engine. Create a template with placeholders like {{name}}, {{order_number}}, {{delivery_date}}, then pass actual values when creating letters or postcards. This enables personalized, scalable direct mail campaigns. Templates are reusable and can be referenced by ID when creating mailings. You can also embed CSS styling for professional-looking mail designs.

How long does it take for mail to be delivered?

Lob prints and mails all items within 24 hours of creation. Delivery time depends on the mail type selected: USPS First Class Mail typically delivers in 2-5 business days, while USPS Standard Mail takes 3-7 business days. You receive a tracking number for each piece of mail to monitor delivery status. Lob also provides expected delivery dates in API responses for planning purposes.

Lob MCP Server for Claude Desktop 21 tools — connect in under 2 minutes

Name: Lob
Availability: InStock
Author: Vinkius

modelcontextprotocol.io/quickstart/user

Built by Vinkius GDPR 21 Tools IDE

Claude Desktop is Anthropic's native application for interacting with Claude AI models on macOS and Windows. It was the first consumer application to ship with built-in MCP support, making it the reference implementation for the Model Context Protocol standard.

Get MCP Server for AI Agents

ASK AI ABOUT THIS MCP SERVER

Open in ChatGPT Open in Claude Open in Perplexity

Vinkius supports streamable HTTP and SSE.

RecommendedModern Approach — Zero Configuration

Vinkius Desktop App

The modern way to manage MCP Servers — no config files, no terminal commands. Install Lob and 2,500+ MCP Servers from a single visual interface.

Download Free Open SourceNo signup required

Classic Setup·json

{
  "mcpServers": {
    "lob": {
      // Your Vinkius token. get it at cloud.vinkius.com
      "url": "https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp"
    }
  }
}

Fully ManagedVinkius Servers

60%Token savings

High SecurityEnterprise-grade

IAMAccess control

EU AI ActCompliant

DLPData protection

V8 IsolateSandboxed

Ed25519Audit chain

<40msKill switch

Stream every event to Splunk, Datadog, or your own webhook in real-time

* 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

Lob MCP Server enables AI agents to send physical mail directly from your applications. Create and mail letters, postcards, and checks programmatically through Lob's print and mail API. Verify US and international addresses, autocomplete partial addresses, and manage your address book. Build reusable HTML templates for personalized mailings. Perfect for automating vendor payments, customer communications, marketing campaigns, payroll checks, and direct mail operations. All mail is printed, processed, and delivered within 24 hours via USPS integration.

Claude Desktop is the definitive way to connect Lob to your AI workflow. Add Vinkius Edge URL to your config, restart the app, and Claude immediately exposes all 21 tools in the chat interface. ask a question, Claude calls the right tool, and you see the answer. Zero code, zero context switching.

The Lob MCP Server exposes 21 tools through the Vinkius. Connect it to Claude Desktop in under two minutes — no API keys to rotate, no infrastructure to provision, no vendor lock-in. Your configuration, your data, your control.

How to Connect Lob to Claude Desktop via MCP

Follow these steps to integrate the Lob MCP Server with Claude Desktop.

Open Claude Desktop Settings

Go to Settings → Developer → Edit Config to open claude_desktop_config.json

Add the MCP Server

Paste the configuration above into the mcpServers section

Restart Claude Desktop

Close and reopen Claude Desktop to load the new server

Start using Lob

Look for the 🔌 icon in the chat. your 21 tools are now available

Why Use Claude Desktop with the Lob MCP Server

Claude Desktop by Anthropic provides unique advantages when paired with Lob through the Model Context Protocol.

Claude Desktop is the reference MCP client. it was designed alongside the protocol itself, ensuring the most complete and stable MCP implementation available

Zero-code configuration: add a server URL to a JSON file and Claude instantly discovers and exposes all available tools in the chat interface

Claude's extended thinking capability lets it reason through multi-step tool usage, chaining multiple API calls to answer complex questions

Enterprise-grade security with local config storage. your tokens never leave your machine, and connections go directly to Vinkius Edge network

Lob + Claude Desktop Use Cases

Practical scenarios where Claude Desktop combined with the Lob MCP Server delivers measurable value.

Interactive data exploration: ask Claude to query DNS records, look up WHOIS data, and cross-reference results in a single conversation

Ad-hoc security audits: type a domain name and let Claude enumerate subdomains, check DNS history, and flag configuration anomalies. all through natural language

Executive briefings: generate comprehensive domain intelligence reports by asking Claude to compile findings into a formatted summary

Learning and training: new team members can explore API capabilities conversationally without needing to read documentation

Lob MCP Tools for Claude Desktop (21)

These 21 tools become available when you connect Lob to Claude Desktop via MCP:

autocomplete_us_address

Autocomplete a partial US address

cancel_letter

Only works if status is still "processing". Cancel a letter before it enters production

create_address

Requires name and address_line1. Create a new address in your Lob address book

create_bank_account

Requires description, routing_number, account_number, account_type (company/individual), and signatory. Add a bank account for sending checks

create_check

Requires recipient (to), bank account ID, and amount. Optional: memo, logo, description. Create and mail a physical check through Lob

create_letter

Requires recipient (to), sender (from), and file content. Supports HTML templates with merge variables, color options, and mail type selection. Create and mail a physical letter through Lob

create_postcard

Requires recipient (to) and front design. Optional: back design, message, merge variables. Create and mail a physical postcard through Lob

create_template

Create a reusable HTML template for mailings

delete_address

Delete an address from your Lob address book

get_address

Get details of a specific address

get_check

Get details of a specific check by ID

get_letter

Get details of a specific letter by ID

get_postcard

Get details of a specific postcard by ID

get_template

Get details of a specific template

list_addresses

Use optional limit to control result count. List addresses in your Lob address book

list_bank_accounts

Use optional limit to control result count. List bank accounts in your Lob account

list_checks

Track payments, audit disbursements. List physical checks sent through Lob

list_letters

Each letter includes status, tracking number, and expected delivery date. Use optional limit to control result count. List physical letters sent through Lob. Track mailings, check delivery status, and review letter history

list_postcards

Use optional limit to control result count. List physical postcards sent through Lob

list_templates

List HTML templates for mailings

verify_us_address

Verify and standardize a US address

Example Prompts for Lob in Claude Desktop

Ready-to-use prompts you can give your Claude Desktop agent to start working with Lob immediately.

"Send a letter to John Doe at 123 Main St, New York, NY 10001 with our welcome package HTML template"

"Verify if this address is deliverable: 185 Berry St, San Francisco, CA 94107"

"Send a $500 check to ABC Consulting for consulting services rendered in March"

Troubleshooting Lob MCP Server with Claude Desktop

Common issues when connecting Lob to Claude Desktop through the Vinkius, and how to resolve them.

Server not appearing after restart

Ensure the JSON is valid (no trailing commas). Check the file path: ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\\Claude\\ (Windows).

Authentication error

Verify your Vinkius token is correct. Go to cloud.vinkius.com to regenerate it if needed.

Tools not showing in chat

Click the 🔌 icon at the bottom of the chat input. If it shows 0 tools, the server may still be connecting. wait a few seconds.

Lob + Claude Desktop FAQ

Common questions about integrating Lob MCP Server with Claude Desktop.

How does Claude Desktop discover MCP tools?

When Claude Desktop starts, it reads the claude_desktop_config.json file and connects to each configured MCP server. It calls the tools/list endpoint to fetch the schema for every available tool, then surfaces them as clickable options in the chat interface via the 🔌 icon.

What happens if the MCP server is temporarily unavailable?

Claude Desktop handles disconnections gracefully. if the server is unreachable at startup, the tools simply won't appear. Once the server becomes available again, restarting Claude Desktop will re-establish the connection. There is no timeout penalty or error loop.

Can I connect multiple MCP servers simultaneously?

Yes. You can add as many servers as you need in the mcpServers section of the config file. Each server appears as a separate tool provider, and Claude can use tools from multiple servers in a single conversation turn.

Is there a limit on the number of tools per server?

Claude Desktop can handle hundreds of tools per server. However, for optimal LLM performance, Vinkius servers are designed to expose focused, well-documented tool sets rather than overwhelming the model with too many options.

Does Claude Desktop support Streamable HTTP transport?

Yes. Claude Desktop supports both SSE (Server-Sent Events) and the newer Streamable HTTP transport that Vinkius uses. Simply provide the server URL. Claude auto-negotiates the transport protocol.