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Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Code & DevOps

Postage Stamp Price MCP

By theluckystrike Verified namespace

How much is a stamp: USPS Forever stamp, postcard, international and letter postage by weight.

Source code
Connect to Postage Stamp Price MCP
Checks passed
14 / 22

0 failed · 8 not measured

Median response
380 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
3

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Outdated check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 380 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name postage-stamp-price-mcp.

  • Pass
    Lists tools

    tools/list returned 3 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 380 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 380 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

    5 of 5 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Not measured
    Website matches publisher

    This namespace is not a reverse domain, so the website comparison does not apply.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Pass
    Repo owner matches

    The GitHub repository owner matches the namespace login.

  • Pass
    Recently updated

    Updated 2026-11-05T18:09:37.463496Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using Postage Stamp Price MCP

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 postage-stamp-price-mcp https://postage-stamp-price-mcp.lipmichal.workers.dev/mcp

Capabilities

Tools 3

calculate_letter_postage

Retail postage for one letter, postcard or large envelope (flat) by weight, to the US, Canada, Mexico or any other country, with the nonmachinable surcharge for square or rigid cards, the total for a quantity, and the number of Forever stamps per piece. Letters up to 3.5 oz, US large envelopes up to 13 oz.

Discovered
get_flat_rate_prices

Current USPS retail prices for Priority Mail Flat Rate envelopes and Small, Medium, Large and APO/FPO/DPO Flat Rate Boxes, and Priority Mail Express Flat Rate envelopes, from Notice 123.

Discovered
get_stamp_price

The current USPS Forever stamp price (First-Class Mail 1 oz stamped letter), the 2, 3 and 3.5 oz prices, metered letter prices, postcard, 1 oz large envelope, the nonmachinable surcharge and the 1 oz international letter (Global Forever) price, read at call time from USPS Notice 123 with its effective date.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected380 ms3

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