# Lob MCP > Lob MCP automates physical mailings, letting your AI agent send letters, postcards, and checks directly from code. It handles everything from address verification and cleansing to creating reusable templates and managing bank accounts for payments. ## Overview - **Category:** customer-support - **Price:** Free - **Tags:** direct-mail, print-api, address-verification, automation, postcards, transactional-mail ## Description Need to send something in the real world? This MCP lets your agent handle physical mail tasks—things like sending payroll checks or running a direct marketing campaign. Instead of manually compiling lists and dropping off stamps, you programmatically create letters, postcards, and even personalized checks. You can verify US addresses for accurate delivery using our address tools, build custom HTML templates, and manage all the necessary details right from your application logic. Vinkius hosts this MCP, giving any compatible client access to every tool needed to automate physical correspondence in one place. ## Tools ### autocomplete_us_address Completes and refines a partial US mailing address into its full format. ### cancel_letter Stops the production process for a letter if it hasn't entered physical manufacturing yet. ### create_address Adds and saves a new mailing address record into your dedicated address book. ### create_bank_account Adds required banking details, like routing and account numbers, needed for check printing. ### create_check Generates a physical payment check and sends it to the recipient using specified funds and bank accounts. ### create_letter Designs, personalizes, and mails a full-sized letter using an HTML template to a specific recipient. ### create_postcard Creates and sends out a physical postcard with custom front and back designs. ### create_template Builds and saves an HTML template that you can reuse for multiple mailings (letters, postcards). ### list_letters Lists all letters ever mailed, showing status and estimated delivery dates for tracking. ### list_postcards Displays a list of every postcard that has been created and sent out. ### list_templates Retrieves the names and details of all HTML templates you've built for mailings. ### verify_us_address Checks if a provided US address is accurate, standardizes it, and confirms its deliverability status. ### delete_address Removes a specific address record from your stored list of mailing addresses. ### get_address Retrieves the full details for one particular saved address by ID. ### get_check Fetches all payment details for a specific check using its unique tracking ID. ### get_letter Retrieves the status and tracking information for an already sent letter by ID. ### get_postcard Gets all details, including delivery status, for a specific postcard mailing. ### get_template Retrieves the content and settings of a previously saved HTML template. ### list_addresses Lists all address records stored in your Lob account, allowing you to control the result count. ### list_bank_accounts Retrieves a list of all bank accounts configured for sending payments and checks. ### list_checks Provides an auditable history of every physical check that has been sent through the system. ## Prompt Examples **Prompt:** ``` Send a letter to John Doe at 123 Main St, New York, NY 10001 with our welcome package HTML template ``` **Response:** ``` I'll create a letter using your welcome package template and send it to the specified address. First, I'll create the recipient address, then create the letter with merge variables for personalization. ``` **Prompt:** ``` Verify if this address is deliverable: 185 Berry St, San Francisco, CA 94107 ``` **Response:** ``` I'll verify the US address to confirm deliverability and standardize the format. This will also add the missing ZIP+4 code and correct any formatting issues. ``` **Prompt:** ``` Send a $500 check to ABC Consulting for consulting services rendered in March ``` **Response:** ``` I'll create a physical check for $500 payable to ABC Consulting. This requires a verified bank account in your Lob account. The check will be printed and mailed within 24 hours via USPS. ``` ## Capabilities ### Verify and clean addresses Validate partial or full US addresses using the `autocomplete_us_address` tool. ### Draft reusable mailing templates Build complex, personalized letter layouts by creating reusable HTML files with the `create_template` tool. ### Generate and send physical letters Create and dispatch formal letters to recipients using the `create_letter` tool. ### Process payments via checks Add bank accounts with `create_bank_account`, then generate and mail physical payments using the `create_check` tool. ### Manage address records Save, retrieve, or delete specific addresses within your dedicated Lob address book. ## Use Cases ### Mass Payroll Distribution The HR team needs to pay 500 employees. Instead of printing checks in batches and manually tracking them, your agent first uses `list_bank_accounts` to confirm company funds, then runs through the employee data list to execute `create_check` for each person, automating payment and logging every check via `list_checks`. ### Customer Onboarding Kits A new customer signs up. The agent uses a stored template (`get_template`) and calls `create_letter`, sending a personalized welcome kit to the verified address retrieved by `autocomplete_us_address`. This completes the entire onboarding sequence in one go. ### Marketing Campaign Cleanup The marketing team has an old mailing list with bad addresses. The agent runs every record through `verify_us_address` to cleanse the data, then uses `list_addresses` to confirm only valid contacts are kept for postcard campaigns. ### Urgent Mail Cancellation A customer needs a letter canceled because they moved. The agent first retrieves the mailing ID using `get_letter`, checks that its status is 'processing,' and then executes `cancel_letter` to stop production immediately. ## Benefits - Accuracy: You eliminate mailing errors by running `verify_us_address` first. This ensures every address, whether it's a partial entry or an international one, is standardized and deliverable before you even start drafting. - Efficiency: Don't manually create documents for payroll. By using `create_template`, you build once, and then use the template with `create_letter` to mass-send personalized notices instantly. - Control: You maintain a clear audit trail of all transactions. Tools like `list_letters` and `list_checks` let your agent track every piece of mail's status and expected delivery date without logging into any third-party portal. - Payment Automation: Sending payments is simple. After adding vendor bank details with `create_bank_account`, you just need to call `create_check` for a physical, mailed payment within 24 hours. - Flexibility: Whether it's formal correspondence (`create_letter`), quick updates (`create_postcard`), or financial payments, this MCP handles the entire lifecycle of sending physical mail items. ## How It Works The bottom line is that you write code once to manage complex, real-world mailing tasks, instead of having to follow a series of manual steps in an external portal. 1. First, use the `autocomplete_us_address` tool to verify and standardize any partial US mailing address you have. 2. Next, build a personalized template using `create_template`, then send out the mail piece—like a postcard or a letter—using its specific creation tool (e.g., `create_postcard`). 3. Finally, your agent executes the request, printing and processing the physical item for delivery within 24 hours via USPS. ## Frequently Asked Questions **How do I verify an address using Lob MCP?** You use the `verify_us_address` tool. It standardizes and confirms deliverability for US addresses, ensuring your mailing list is accurate before sending anything. **Can I send checks with this MCP?** Yes. First, you must use `create_bank_account` to add the necessary bank details. Then, calling `create_check` sends a physical check that gets logged in your system. **What if I need to change a letter after sending it?** You can first retrieve the item's status using `get_letter`. If it hasn't been produced yet, you can use `cancel_letter` to halt the process immediately. **How do I manage my list of addresses?** You can store and retrieve addresses using `create_address` to save them or use `list_addresses` to see all records. You can also clean up old data with `delete_address`. **Does this MCP support custom designs?** Yes, you first build the layout using `create_template`, which accepts HTML code and merge variables, allowing for highly personalized mailings. **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.