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Lob MCP by usefulapi

by m190version 1.36.3i★ –iRuns in the cloud
Registry nameio.usefulapi/lob

Install

Overview

Description from the maker (original English)

Verify US & international addresses and send physical mail (postcards, letters, checks) via Lob.

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

Install

Pick the AI app you use, then copy the settings.

Before you install

  • Basic checks: 3 of 3 passed
  • Runs on the maker’s server: what you ask it goes through their server.
  • Can do 18 things (tools) lob_verify_us_address, lob_verify_intl_address, lob_us_zip_lookup, lob_us_autocomplete …
  • The registry lists no key to fill in.

You need

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

Works in Claude on the web, desktop and mobile:

  1. Open Settings → Connectors
  2. Press Add custom connector
  3. Paste the address below and press Add
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Add2https://…3
https://lob.usefulapi.io/mcp

Run this in your terminal

claude mcp add --transport http lob https://lob.usefulapi.io/mcp

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "lob": {
      "url": "https://lob.usefulapi.io/mcp"
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "lob": {
      "type": "http",
      "url": "https://lob.usefulapi.io/mcp"
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

ChatGPT connects only to servers on the internet:

  1. Open ChatGPT on the web → Settings → Connectors (Apps)
  2. Press Create or Add (some plans need Developer mode under Advanced first)
  3. Paste the address below, give it a name and save
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Create2https://…3
https://lob.usefulapi.io/mcp

Menu names can differ slightly by plan and over time.

Your choice stays on this device in a cookie; no account needed.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Tool names and descriptions exactly as the server reported them on Nov 6, 2026. The maker wrote them, not us; we show them as plain text.

  • lob_verify_us_address

    Validate & standardize a US address, returning deliverability, corrected components, and a confidence score. Pass either a single freeform `address` string OR structured `primary_line`/`city`/`state`/`zip_code`. Non-mutating (no mail sent). Lob API: POST /v1/us_verifications.

  • lob_verify_intl_address

    Validate & standardize a non-US address. `country` (2-letter ISO code) is required. Non-mutating (no mail sent). Lob API: POST /v1/intl_verifications.

  • lob_us_zip_lookup

    Return the cities and state associated with a US ZIP code. Non-mutating. Lob API: POST /v1/us_zip_lookups.

  • lob_us_autocomplete

    Suggest complete US addresses from a partial primary line — useful for address entry. Non-mutating. Lob API: POST /v1/us_autocompletions.

  • lob_list_postcards

    List sent/scheduled postcards, newest first. Lob API: GET /v1/postcards.

  • lob_get_postcard

    Retrieve a single postcard by id, including status, PDF url, and expected delivery. Lob API: GET /v1/postcards/{id}.

  • lob_list_letters

    List sent/scheduled letters, newest first. Lob API: GET /v1/letters.

  • lob_get_letter

    Retrieve a single letter by id, including status, PDF url, and tracking. Lob API: GET /v1/letters/{id}.

  • lob_list_checks

    List sent/scheduled checks, newest first. Lob API: GET /v1/checks.

  • lob_get_check

    Retrieve a single check by id, including amount, status, and check number. Lob API: GET /v1/checks/{id}.

  • lob_list_self_mailers

    List sent/scheduled self-mailers, newest first. Lob API: GET /v1/self_mailers.

  • lob_list_addresses

    List saved address records, newest first. Lob API: GET /v1/addresses.

  • lob_get_address

    Retrieve a single saved address record by id. Lob API: GET /v1/addresses/{id}.

  • lob_list_templates

    List saved HTML templates usable as postcard/letter artwork. Lob API: GET /v1/templates.

  • lob_create_address

    Create a reusable saved address record (does NOT send any mail). Returns an address id (adr_…) usable as `to`/`from` in mail tools. Lob API: POST /v1/addresses.

  • lob_create_postcard

    ⚠️ SENDS A REAL POSTCARD and charges your Lob account (use a test_ key to avoid real mail/charges). `to` and `from` accept an existing address id (adr_…) or an inline address object. `front`/`back` accept an HTML string, a hosted asset URL, or a template id (tmpl_…). Cancelable o

  • lob_create_letter

    ⚠️ SENDS A REAL LETTER and charges your Lob account (use a test_ key to avoid real mail/charges). `to`/`from` accept an address id (adr_…) or inline object. `file` accepts an HTML string, a hosted PDF/URL, or a template id (tmpl_…). `color` is required. Cancelable only before `se

  • lob_cancel_postcard

    Cancel a postcard before its send_date so it is never mailed (and not billed). Fails if the send window has passed. Lob API: DELETE /v1/postcards/{id}.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 6, 2026

  • ✓ Pass

    Maker matches the repo

    The registry name was verified against the domain usefulapi.io (the registry checks domain ownership)

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • ✓ Pass

    Endpoint responds

    Responded in 95 ms (HTTP 200)

  • – Not applicable

    Sign-in with OAuth

    No sign-in needed

  • ✓ Pass

    No hidden instructions in tool descriptions

    Read 18 tool descriptions and found no hidden instructions to the AI

Compared with others in Otheri

  • More stars than 0% of the other 32410 servers in this category
  • Published to the registry more recently than 97% of the other 32410 servers in this category
  • Basic checks equal to or better than 100% of the other 32410 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is Lob MCP by usefulapi safe?

It passed 3 of 3 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

The registry does not list a required key, though some servers ask you to sign in on first use.

Does it run on my computer or in the cloud?

It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.36.3) reached the registry yesterday.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.

What can I use instead?

In the same category: Spec Driven Development, Remote Desktop Commander, debuff

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Spec Driven Development

by formulahendry

MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.

Runs on your computer★ 440MITUpdated 14 months ago
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Remote Desktop Commander

by desktop-commander

Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.

Runs in the cloud★ 211Updated yesterday
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debuff

by debuffjp

Let coding agents play, test and tune your 2D web game: live state, explained errors, replays, fuzz.

Runs on your computerUpdated today
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README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

Lob MCP by usefulapi

Verify addresses and send physical mail via Lob, from Claude, Cursor, or any MCP client. Hosted, no local install — connect with your Lob API key.

Live endpoint: https://lob.usefulapi.io/mcp · Homepage: https://usefulapi.io/lob

Connect

  • Claude (claude.ai, Desktop): open Customize → Connectors, click + Add → Add custom connector, and paste https://lob.usefulapi.io/mcp.
  • Claude Code: claude mcp add --transport http lob https://lob.usefulapi.io/mcp, then run /mcp to log in.
  • VS Code: Add to VS Code.
  • Cursor and other clients: add the URL as a remote MCP server:
{

"mcpServers": { "lob": { "url": "https://lob.usefulapi.io/mcp" } } }

Add only the URL. Do not add an Authorization header or an API key to the client config: the server signs you in with OAuth, and the login page asks for your Lob credentials.

Step-by-step setup, where to find your credentials, and FAQ: https://usefulapi.io/lob/

On first connect you'll paste your Lob API key. It's validated, stored per-user, and scoped to you.

Tools

ToolTypeWhat it does
lob_verify_us_addressreadVerify a US address
lob_verify_intl_addressreadVerify an international address
lob_us_zip_lookupreadLook up a US ZIP code
lob_us_autocompletereadAutocomplete a US address
lob_list_postcardsreadList postcards
lob_get_postcardreadGet a postcard
lob_list_lettersreadList letters
lob_get_letterreadGet a letter
lob_list_checksreadList checks
lob_get_checkreadGet a check
lob_list_self_mailersreadList self-mailers
lob_list_addressesreadList saved addresses
lob_get_addressreadGet a saved address
lob_list_templatesreadList templates
lob_create_addresswriteSave an address record
lob_create_postcardwriteSend a postcard (COSTS MONEY)
lob_create_letterwriteSend a letter (COSTS MONEY)
lob_cancel_postcardwriteCancel a scheduled postcard
lob_usage_statusmetaUsage status (free-tier meter)
lob_request_featuremetaRequest a missing feature
lob_upgrademetaUpgrade to Pro or Pro+
lob_cancel_subscriptionmetaCancel the Pro subscription

read tools are read-only; write tools mutate data (clients should confirm them); meta tools report usage, manage your subscription or send a feature request.

Pricing

PlanPriceLimit
Free$050 tool calls / month
Pro$9/mo or $90/yr (2 months free)Unlimited*

\*Pro has a fair use limit of 10,000 tool calls a month on this server. For more, write to support@usefulapi.io.

Pro covers this server only. Subscribe with lob_upgrade (it returns a Stripe Checkout link). Cancel any time with lob_cancel_subscription: Pro continues to the end of the paid period, with no refund for the current period, and running lob_upgrade before then undoes the cancel. Or write to support@usefulapi.io.

License

MIT — see LICENSE. Documentation only; the server is hosted.

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