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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

StringSpec

Lab measurements of nearly 800 tennis strings: search, compare and get recommendations.

Checks passed
15 / 22

0 failed · 7 not measured

Median response
873 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
4

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 1000 ms.

  • Pass
    Valid handshake

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

  • Pass
    Lists tools

    tools/list returned 4 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 873 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 987 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

    17 of 17 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.

  • 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 2026-10-07T17:32:12.996119Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using StringSpec

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 stringspec https://stringspec.com/mcp

Capabilities

Tools 4

compare_strings

Side-by-side measurements, percentiles, prices and buy links for 2 or 3 strings by name, with the StringSpec comparison page when there are two.

Discovered
get_string

Everything StringSpec has on one string, found by name (misspellings and missing gauges are fine): every measurement with its database percentile, elongation at 40, 51 and 62 lb, an estimated playable life, a tension adjustment versus the player's usual, how it ranks for each playing need (spin, comfort, control, power, tension hold, durability, feel), the closest alternatives, the retail price and a buy link. When the name matches several strings it returns the best match and lists the others.

Discovered
recommend_strings

Rank the database for what a player wants, with StringSpec's string finder: one main need and an optional second one (spin (More spin and shape), comfort (Easier on my arm), control (More control, less launch), power (More power and depth), hold (Plays the same for longer), durable (Lasts longer before it breaks), feel (Best feel and touch)), adjusted for the racquet (string pattern, head size, frame stiffness) and with a material ruled out if asked. Returns a shortlist with a 0-100 fit, why each string fits, its price and buy link, and the finder link with the same answers filled in. For arm or elbow pain use need "comfort", and avoid "poly" when the player wants no polyester.

Discovered
search_strings

Search 791 lab-measured tennis strings by name, brand, material and gauge, sorted by a measurement or by price. Each result carries stiffness (lb/in), tension loss (%), energy return (%), spin potential, ball bite and string friction, each with its percentile in the database, plus the current retail price, a buy link and the StringSpec page. Returns at most 10 strings; narrow the filters rather than asking for more.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected1000 ms4
Connected745 ms4