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MCP server · Code & DevOps

Lob MCP by usefulapi

By usefulapi.io Verified namespace

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

WebsiteSource code
Connect to Lob MCP by usefulapi
Checks passed
14 / 22

0 failed · 8 not measured

Median response
54 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
18

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 54 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name lob-mcp.

  • Pass
    Lists tools

    tools/list returned 18 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 54 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 54 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    65 of 71 parameters have a description (92%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-11-10T23:33:28.763194Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using Lob MCP by usefulapi

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

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

Capabilities

Tools 18

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}.

Discovered
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.

Discovered
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 `send_date`. Tracked mail: `extra_service` = certified (U.S. addresses: tracking + proof of delivery), certified_return_receipt (certified + the recipient's electronic signature) or registered (international addresses only); extra cost, first class only, not for us_legal size. The tracking number is on the letter (lob_get_letter). Lob API: POST /v1/letters.

Discovered
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 only before `send_date`. Lob API: POST /v1/postcards.

Discovered
lob_get_address

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

Discovered
lob_get_check

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

Discovered
lob_get_letter

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

Discovered
lob_get_postcard

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

Discovered
lob_list_addresses

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

Discovered
lob_list_checks

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

Discovered
lob_list_letters

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

Discovered
lob_list_postcards

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

Discovered
lob_list_self_mailers

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

Discovered
lob_list_templates

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

Discovered
lob_us_autocomplete

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

Discovered
lob_us_zip_lookup

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

Discovered
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.

Discovered
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.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected54 ms18

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