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Card Mailer

REMOTE · CARDS.ONMAX.ME

Print and mail 5x7 holiday and thank-you photo cards to a US address list. $2.49/card incl. postage.

Available components

+3 this week 63 Trust /100

Last scanned (2 hours ago)

Scores higher than 44% of remote servers

Reachable. Last reached 5 Nov 2026.

Category Documents and Files

Trust breakdown (7 categories)

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →

Endpoint Security46
Transport & Reachability100
Schema Quality & AI Usability76
  • 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
  • AI-judged instruction clarity (good).Pass
  • Context-footprint check failed: tool/resource definitions use about 1441 tokens (~160/item across 9 items; 6 tools + 3 resources), over budget; trim descriptions and params. See how to fix → Fail
  • Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management30
  • Stability check failed: schema churn in the 12 days we've observed: 0 tool removals, 1 breaking changes, 0 auth/transport breaks, 0 additions. See how to fix → Fail
Tool Coverage88
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 57% of tool parameters carry a description.Partial
  • Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
  • No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
  • We read all 6 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
  • An AI judge read all 8 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
  • Implements a current MCP spec version (2026-07-28).Pass
  • Supports UI / widget rendering.Pass
Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 5 Nov 26 0
    • Resource “Card Mailer widget legacy” now points somewhere else: ui://widget/card-mailer-06e86234e1033466.html → ui://widget/card-mailer-v1.html security
  • 4 Nov 26 +1
    • Resource “Card Mailer widget legacy” now points somewhere else: ui://widget/card-mailer-06e86234e1033466.html → ui://widget/card-mailer-v1.html security
  • 2 Nov 26 +1
    • Resource “Card Mailer widget current” now points somewhere else: ui://widget/card-mailer-06e86234e1033466.html → ui://widget/card-mailer-51779a33fd005602.html security
  • 31 Oct 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 10 to 13.

  • 30 Oct 26 0
    • Tool “fix_address” rewrote its description, which is the text the model reads security
    • Tool “import_address_list” rewrote its description, which is the text the model reads security
  • 29 Oct 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 3 to 6.

  • 26 Oct 26 0
    • Stability: 0.03 → fail ▼ security
    • A breaking change shipped without a version bump: still 1.0.0 ▼ security
    • The server rewrote its instructions, which are the text every model session reads security
    • Tool “quote_mailing” rewrote its description, which is the text the model reads security
    • Schema quality: 1173 → 1364 ▼ functional
    • “quote_mailing” added a required parameter “design_id”, so existing callers break ▼ functional
    • Resource “Card Mailer widget” was removed ▼ functional
    • New resource “Card Mailer widget legacy” functional
    • New resource “Card Mailer widget current” functional
  • 25 Oct 26 0
    • Stability: unverified → 0.03 ▲ functional
Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 5 Nov 2026 · Probed https://cards.onmax.me/mcp/claude

TLS valid

Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .

Subject Issuer Valid from Valid until Key Signature Serial
CN=onmax.me CN=WE1,O=Google Trust Services,C=US 22 Oct 2026 20 Jan 2027 ECDSA 256 ECDSA-SHA256 41dd28f2dde14afa1307bcdbdcb18cba
SANs: onmax.me, cards.onmax.me, *.cards.onmax.me
CN=WE1,O=Google Trust Services,C=US (CA) CN=GTS Root R4,O=Google Trust Services LLC,C=US 13 Dec 2023 20 Feb 2029 ECDSA 256 ECDSA-SHA384 7ff31977972c224a76155d13b6d685e3
CN=GTS Root R4,O=Google Trust Services LLC,C=US (CA) CN=GlobalSign Root CA,OU=Root CA,O=GlobalSign nv-sa,C=BE 15 Nov 2023 28 Jan 2028 ECDSA 384 SHA256-RSA 7fe530bf331343bedd821610493d8a1b

Background: What to check on a remote MCP endpoint →

DNSSEC insecure

Validation of cards.onmax.me. — Not signed

Zone DS Keys Algorithms Outcome
. trust_anchor 20326, 38696 8, 8 Verified
me. present 45352 8 Verified
onmax.me. absent Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation
Authentication No authorisation required

The endpoint answered without asking for a token. Anyone who knows the URL can reach it.

Result No authorisation required
HTTP status 200

Background: How OAuth 2.1 works in the 2026 MCP spec →

Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://cards.onmax.me/mcp/claude Verified 200
http (plaintext) http://cards.onmax.me/mcp/claude Inconclusive 405
MCP tools · 6 exposed · ~1,221 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →

Tool Tokens
create_mailing ~163

Use this when the user has seen the card and the quote and says they want to order. Creates an unpaid order for the ready recipients in list_id with design_id and returns a link to cards.onmax.me, where the user reviews the recipients and pays. Nothing is printed, mailed or charged until the user pays on that page. Recipients that still need fixing are left out. Each call creates a separate order link, so call it once per order. Optional sender is printed as the US return address.

NameTypeReqDescription
arrive_bystring––
design_idstringyes–
list_idstringyes–
send_datestring–Date to print and mail, YYYY-MM-DD.
senderobject–Return address (US).
NameTypeReqDescription
arrives_betweenarrayyes–
checkout_urlstringyes–
design_idstringyes–
kindstringyes–
latest_send_datestring––
list_idstringyes–
mailing_idstringyes–
needs_fixingnumberyes–
notesarrayyes–
on_timeboolean––
quantitynumberyes–
send_datestringyes–
totalstringyes–
total_centsnumberyes–
unit_pricestringyes–

No examples provided.

design_card ~273

Use this to create or edit the printed 5x7 postcard: a greeting on the front over or under the photo, and a message and sign-off on the back. Pass the photo the user attached as photo, or a public https image URL as photo_url; the image is downloaded and stored on cards.onmax.me. Without a photo the front is the greeting on a solid color. Pass design_id to edit a design: given fields replace the old values and omitted fields keep them. Use the message the user wrote or approved, up to 500 characters. Places the user's photo and text in a print template; does not generate images.

NameTypeReqDescription
design_idstring––
greetingstring–Front headline, e.g. "Happy Holidays", "Merry Christmas", "Thank You".
messagestring–Message printed on the back.
photoobject–Photo the user attached for the front.
photo_urlstring–Public https URL of the front photo.
remove_photoboolean––
sign_offstring–Signature on the back, e.g. "Love, The Garcias".
stylestring–classic (red), evergreen (green), winter (blue), minimal (white), thanks (warm, for thank-you cards).
NameTypeReqDescription
design_idstringyes–
greetingstringyes–
has_photobooleanyes–
kindstringyes–
messagestringyes–
photo_warningstring|nullyes–
sign_offstringyes–
stylestringyes–

No examples provided.

fix_address ~202

Use this to correct or remove one recipient in a list from import_address_list, by row number. Given fields replace the stored values and omitted fields keep theirs; if the row's problem says it could not be read, pass name, line1, city, state and zip together. Re-runs the required-field and US address format checks, plus USPS verification when it is configured. Format checks alone do not confirm that an address is deliverable. remove: true takes the recipient out of the mailing. Rows in a list that belongs to a paid order cannot be changed.

NameTypeReqDescription
citystring––
line1string–Street address
line2string–Apartment, suite, unit
list_idstringyes–
namestring––
removeboolean–Remove this recipient from the mailing.
rowintegeryes–
statestring––
zipstring––
NameTypeReqDescription
corrected_by_uspsnumberyes–
kindstringyes–
list_idstringyes–
needs_fixingnumberyes–
problemsarrayyes–
readynumberyes–
skipped_over_limitnumber––
totalnumberyes–
usps_checkedboolean––

No examples provided.

get_mailing_status ~84

Use this when the user asks whether a Card Mailer order was paid, printed, mailed or delivered. Takes the mailing_id returned by create_mailing (also the last part of the order link). Returns the status, send date, expected arrival and per-recipient counts. Does not change the order or track other USPS mail.

NameTypeReqDescription
mailing_idstringyes–
NameTypeReqDescription
addresses_deletedbooleanyes–
arrives_betweenarrayyes–
checkout_urlstringyes–
countsobjectyes–
kindstringyes–
mailing_idstringyes–
quantitynumberyes–
send_datestringyes–
statusstringyes–
totalstringyes–

No examples provided.

import_address_list ~226

Use this when the user wants to mail printed cards to people at US postal addresses and gives the addresses as pasted text, a CSV, or an .xlsx spreadsheet. Reads names and addresses, checks required fields and US address format, and saves them as a recipient list. USPS verification runs only when it is configured; usps_checked in the result says whether it ran. Format checks alone do not confirm that an address is deliverable. Returns a list_id, how many rows are ready, and the problem for each row that needs fixing. Up to 300 recipients; pass list_id to append rows to an existing list. US addresses only. Not for e-cards or email, addresses outside the US, or advertising mail to purchased or rented lists.

NameTypeReqDescription
address_fileobject–A CSV or XLSX file the user attached.
addresses_textstring–Addresses as pasted text or CSV. One recipient per line ("Name, Street, City, ST ZIP") or a CSV with a header row.
list_idstring–Existing list to append to.
NameTypeReqDescription
corrected_by_uspsnumberyes–
kindstringyes–
list_idstringyes–
needs_fixingnumberyes–
problemsarrayyes–
readynumberyes–
skipped_over_limitnumber––
totalnumberyes–
usps_checkedboolean––

No examples provided.

quote_mailing ~273

Use this when the user asks what mailing a card to an imported list costs or when it will arrive. Returns the price per card (First-Class postage included), the total for the ready recipients, the send date and the expected arrival window. For a card preview with the price, first create or edit it with design_card, then pass that exact design_id here. This shows the current saved front and back above the quote. design_id is required: use null only when the user requested a price-only quote without a design. Never claim a preview is shown when preview_included is false. If the cards must arrive by a date, pass arrive_by; the result gives the latest safe send date and whether that date can be met. Does not create an order or charge anything.

NameTypeReqDescription
arrive_bystring–Date the cards should arrive by, YYYY-MM-DD.
design_idstring|nullyesRequired preview choice. Use the exact design_id returned by design_card for a preview with price. Use null only for a price-only request without a design. Do not omit.
list_idstringyes–
send_datestring–Date to print and mail, YYYY-MM-DD. Default: the latest safe date for arrive_by, otherwise the earliest business day (today if it is one).
NameTypeReqDescription
arrives_betweenarrayyes–
design_idstring––
kindstringyes–
latest_send_datestring––
needs_fixingnumberyes–
notesarrayyes–
on_timeboolean––
preview_includedbooleanyes–
quantitynumberyes–
send_datestringyes–
totalstringyes–
total_centsnumberyes–
unit_pricestringyes–

No examples provided.

Install

How do I install the Card Mailer MCP server?

Card Mailer is a hosted endpoint at https://cards.onmax.me/mcp/claude, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

remote · cards.onmax.me

# add to Claude Code
claude mcp add --transport http me-onmax-card-mailer 'https://cards.onmax.me/mcp/claude'
Common questions

What is the Card Mailer MCP server?

Card Mailer is an MCP server listed in the public MCP registry as me.onmax/card-mailer. Print and mail 5x7 holiday and thank-you photo cards to a US address list. $2.49/card incl. postage. This page covers its hosted endpoint (https://cards.onmax.me/mcp/claude).

Is the Card Mailer MCP server safe to use?

Card Mailer scores 63 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

What tools does the Card Mailer MCP server expose?

Card Mailer exposes 6 tools: import_address_list, fix_address, design_card, quote_mailing, create_mailing, get_mailing_status. Their descriptions and schemas cost roughly 1,221 tokens of context every time the server is loaded.

Does the Card Mailer MCP server require authentication?

No. We connected to Card Mailer without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

Is the Card Mailer MCP server still maintained?

Card Mailer is still listed as active in the MCP registry. We last reached this channel on 5 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.