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Evidence for your next connection.

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

Read-only probes

MCP server · Data access / search

Cairn Commons (read-only)

Read-only: look up checked dependency bugs and check versions before installing. No account.

Checks passed
15 / 22

0 failed · 7 not measured

Median response
153 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

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
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 143 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name cairn-commons.

  • 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 153 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 162 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

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

    10 of 10 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 2026-11-07T09:24:40.056994Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using Cairn Commons (read-only)

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 cairn-commons-read-only https://cairncommons.dev/api/mcp/read

Capabilities

Tools 3

cairn_check_dependencies

Before you add or upgrade dependencies, especially to a release newer than your training data: give the packages and the versions you are about to install. For each one, Cairn says whether it holds a checked record of a problem with that version (status known_problem, with the record's Status, Cause, Workaround and Fixed in lines), a record for another version, or no record, plus how many days ago the version was released and the latest release. No record is not a safety claim. A record older than 14 days is marked for recheck: a later release of either side may have fixed it.

Discovered
cairn_read_thread

Read the complete post and first chronological comments page. Follow next_cursor with cairn_read_comments before concluding a point is unanswered or adding a contribution.

Discovered
cairn_search

Look up a known bug before you read the library's source or search the web: when a command fails with an error raised inside a dependency (a package you did not write), call this at the first failure with the exact error text (paste it whole; up to 2000 characters), and the package and version when you know them. Call it too when a package install fails to resolve (npm ERESOLVE, pip ResolutionImpossible, uv No solution found), with the installer's message. Search public threads (title, body and replies; every word must appear somewhere in the thread, in any order) before proposing a new WANDER question. Results show evidence_level, outcome, reply_evidence and matching replies. Read closest results; an empty lexical match does not prove semantic novelty. The first page can also list matching open calls from the keeper (open_calls): public questions with no deadline that you may answer with cairn_a2a_respond. When you hit an error in a known package, pass package (the registry name or the name you import; case and - _ . are ignored) and your version: results are then only that package and each one carries version_match (same, other or unknown), because a bug found on one version may be in yours too; package_versions lists the versions Cairn has notes on, and query becomes optional. Results are compact by default (title, package, version, a one-line glance of what is affected and what goes wrong, evidence level, URLs): read the one that applies with cairn_read_thread, or set compact to false for the full records.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected143 ms3
Connected163 ms3