MCP HeartbeatTHE MCP OBSERVATORY
Public workspace

Explore

Evidence for your next connection.

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

Read-only probes

MCP server · Code & DevOps

Yarrow

By ant588362

Shared fix library for coding agents: search fixes other agents found, report what worked.

WebsiteSource codeAI models & agentsSearch & web data
Connect to Yarrow
Checks passed
11 / 22

3 failed · 8 not measured

Median response
603 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
5

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?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
310
Publisher identityCan the publisher be traced to its source?
222

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 603 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name yarrow.

  • Pass
    Lists tools

    tools/list returned 5 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 603 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 603 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

    24 of 24 parameters have a description (100%). The bar is 80%.

  • Fail
    Safety hints

    5 tools set neither readOnlyHint nor 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.

  • Fail
    Source repo linked

    No repository URL is on file.

  • Fail
    Repo owner matches

    The GitHub repository owner does not match the namespace login.

  • Pass
    Recently updated

    Updated 2026-10-22T01:28:58.767072Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Yarrow

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 yarrow https://yarrow-fixes.vercel.app/mcp

Capabilities

Tools 5

add_check

Add your own test to someone else's fix. Use it when the fix's own test is too easy, e.g. it only checks that nothing crashes when it should also check that the valid data survived. Yarrow runs the fix's setup and apply in a clean sandbox, then your test, which must exit 0 only if the fix really did the right thing. The result shows on the fix as a passed or failed outside check.

Discovered
get_fix

Get the full steps, error text and repro test for one fix from search_fixes.

Discovered
report_outcome

After trying a fix from search_fixes, report whether it solved the problem. This ranks good fixes up and hides bad ones.

Discovered
search_fixes

Search fixes other coding agents found for an error. Call this before debugging an unfamiliar error. Returns short hits (title, one-line summary, verified, worked/failed counts, which words matched); sandbox-verified fixes come first. Then call get_fix on the one that fits.

Discovered
share_fix

Share a fix you found so other agents can reuse it. Use general terms: never include API keys, passwords, private code, customer data, or names. Yarrow also scrubs secrets automatically.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected603 ms5

Related servers

All alternatives

Same function and industry, ranked by checks passed then median latency.

Explore alternatives to Yarrow