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 Windsurf 21 tools — connect in under 2 minutes

Name: Lob
Availability: InStock
Author: Vinkius

docs.windsurf.com/windsurf/mcp

Built by Vinkius GDPR 21 Tools IDE

Windsurf brings agentic AI coding to a purpose-built IDE. Connect Lob through the Vinkius and Cascade will auto-discover every tool — ask questions, generate code, and act on live data without leaving your editor.

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": {
      "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.

Windsurf's Cascade agent chains multiple Lob tool calls autonomously — query data, analyze results, and generate code in a single agentic session. Paste the Vinkius Edge URL, reload, and all 21 tools are immediately available. Real-time tool feedback appears inline, so you see API responses directly in your editor.

The Lob MCP Server exposes 21 tools through the Vinkius. Connect it to Windsurf 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 Windsurf via MCP

Follow these steps to integrate the Lob MCP Server with Windsurf.

Open MCP Settings

Go to Settings → MCP Configuration or press Cmd+Shift+P and search "MCP"

Add the server

Paste the JSON configuration above into mcp_config.json

Save and reload

Windsurf will detect the new server automatically

Start using Lob

Open Cascade and ask: "Using Lob, help me..." — 21 tools available

Why Use Windsurf with the Lob MCP Server

Windsurf provides unique advantages when paired with Lob through the Model Context Protocol.

Windsurf's Cascade agent autonomously chains multiple tool calls in sequence, solving complex multi-step tasks without manual intervention

Purpose-built for agentic workflows — Cascade understands context across your entire codebase and integrates MCP tools natively

JSON-based configuration means zero code changes: paste a URL, reload, and all 21 tools are immediately available

Real-time tool feedback is displayed inline, so you see API responses directly in your editor without switching contexts

Lob + Windsurf Use Cases

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

Automated code generation: ask Cascade to fetch data from Lob and generate models, types, or handlers based on real API responses

Live debugging: query Lob tools mid-session to inspect production data while debugging without leaving the editor

Documentation generation: pull schema information from Lob and have Cascade generate comprehensive API docs automatically

Rapid prototyping: combine Lob data with Cascade's code generation to scaffold entire features in minutes

Lob MCP Tools for Windsurf (21)

These 21 tools become available when you connect Lob to Windsurf 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 Windsurf

Ready-to-use prompts you can give your Windsurf 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 Windsurf

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

Server not connecting

Check Settings → MCP for the server status. Try toggling it off and on.

Lob + Windsurf FAQ

Common questions about integrating Lob MCP Server with Windsurf.

How does Windsurf discover MCP tools?

Windsurf reads the mcp_config.json file on startup and connects to each configured server via Streamable HTTP. Tools are listed in the MCP panel and available to Cascade automatically.

Can Cascade chain multiple MCP tool calls?

Yes. Cascade is an agentic system — it can plan and execute multi-step workflows, calling several tools in sequence to accomplish complex tasks without manual prompting between steps.

Does Windsurf support multiple MCP servers?

Yes. Add as many servers as needed in mcp_config.json. Each server's tools appear in the MCP panel and Cascade can use tools from different servers in a single flow.