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StringSpec

by BigBalliversion 1.0.0i★ –iRuns in the cloud
Registry namecom.stringspec/mcp

Install

Overview

Description from the maker (original English)

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

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

  • Connection: Runs in the cloud
  • Transport: Streamable HTTP
  • Category: Search & AI memory

Install

Pick the AI app you use, then copy the settings.

Before you install

  • Basic checks: 1 of 1 passed
  • Runs on the maker’s server: what you ask it goes through their server.
  • The registry lists no key to fill in.

You need

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

Works in Claude on the web, desktop and mobile:

  1. Open Settings → Connectors
  2. Press Add custom connector
  3. Paste the address below and press Add
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Add2https://…3
https://stringspec.com/mcp

Run this in your terminal

claude mcp add --transport http stringspec https://stringspec.com/mcp

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "stringspec": {
      "url": "https://stringspec.com/mcp"
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "stringspec": {
      "type": "http",
      "url": "https://stringspec.com/mcp"
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

ChatGPT connects only to servers on the internet:

  1. Open ChatGPT on the web → Settings → Connectors (Apps)
  2. Press Create or Add (some plans need Developer mode under Advanced first)
  3. Paste the address below, give it a name and save
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Create2https://…3
https://stringspec.com/mcp

Menu names can differ slightly by plan and over time.

Your choice stays on this device in a cookie; no account needed.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

We have not read this server’s tool list yet; we check endpoints in rotation.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 6, 2026

  • ✓ Pass

    Maker matches the repo

    The registry name was verified against the domain stringspec.com (the registry checks domain ownership)

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • … Not checked yet

    Endpoint responds

    Not checked yet; we check endpoints in rotation

  • … Not checked yet

    Sign-in with OAuth

    Not checked yet; we check endpoints in rotation

  • … Not checked yet

    No hidden instructions in tool descriptions

    Not checked yet; we read the tool list when we check the endpoint

Compared with others in Search & AI memoryi

  • More stars than 0% of the other 7223 servers in this category
  • Published to the registry more recently than 56% of the other 7223 servers in this category
  • Basic checks equal to or better than 100% of the other 7223 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is StringSpec safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

The registry does not list a required key, though some servers ask you to sign in on first use.

Does it run on my computer or in the cloud?

It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.0.0) reached the registry 29 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.

What can I use instead?

In the same category: Context7, Codebase Memory, Exa

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Context7

by upstash

Feeds AI the latest docs for libraries and frameworks before it answers, so code it writes does not use outdated, removed functions.

Computer or cloud★ 64,224MITUpdated 3 days ago
Install

Codebase Memory

by DeusData

Codebase knowledge graph for AI agents — 162 languages, sub-ms queries, 99% fewer tokens.

Runs on your computer★ 48,148MITUpdated 20 days ago
Install

Exa

by exa-labs

Connect AI agents to Exa for web search, content fetching, and multi-step research.

Runs in the cloud★ 5,213MITUpdated 44 days ago
Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

StringSpec for Claude and other MCP clients

Ask an AI assistant about tennis strings and get answers from lab measurements instead of marketing copy: how stiff a string is, how fast it loses tension, how much energy it returns, how much spin it allows, and which strings suit a player's needs and racquet.

This repository holds:

  • the connection details for the StringSpec remote MCP server at https://stringspec.com/mcp,
  • a Claude plugin that adds that server plus a string-research skill, which teaches Claude how to read the numbers.

The server is run by StringSpec, a database of nearly 800 tennis strings measured on the same machine under the same protocol, so one string's numbers compare fairly with another's. How the numbers are made: methodology.

What you can ask

  • "Which polyester strings are the softest, and what do they cost?"
  • "How fast does Solinco Hyper-G 16 lose tension, and how long will it stay playable?"
  • "Compare RPM Blast 17 with Luxilon ALU Power 16L."
  • "I have tennis elbow and a stiff racquet. What should I string, without natural gut?"
  • "What should I string for more spin on an 18x20 racquet?"

Tools

All tools are read-only (readOnlyHint: true) and need no account.

ToolWhat it answers
search_stringsFilter by name, brand, material, gauge and price; sort by popularity, softest, stiffest, most spin, best tension hold, most power or cheapest. At most 10 strings per call.
get_stringEverything on one string, found by name: every measurement with its percentile in the database, elongation at 40, 51 and 62 lb, an estimated playable life, a tension adjustment, how it ranks for spin, comfort, control, power, tension hold, durability and feel, the closest alternatives, and the retail price.
compare_stringsTwo or three strings side by side, with the comparison page on stringspec.com.
recommend_stringsStringSpec's string finder: a main need and an optional second one, adjusted for the racquet (string pattern, head size, frame stiffness), with a material ruled out if asked. Returns a ranked shortlist with a 0 to 100 fit and the reason each string fits.

Every answer separates measurements from estimates (playable life, tension advice and fit are derived from the measurements) and dates each price.

Setup

Claude (claude.ai, Desktop, mobile)

Settings → Connectors → Add custom connector, then paste https://stringspec.com/mcp. No sign-in is needed.

Claude Code

Install the plugin, which adds the server and the string-research skill:

/plugin marketplace add BigBalli/stringspec-mcp

/plugin install stringspec@stringspec

Or add only the server:

claude mcp add --transport http stringspec https://stringspec.com/mcp
Other MCP clients

Any client that supports remote MCP servers over Streamable HTTP can use https://stringspec.com/mcp with no credentials. The server speaks protocol versions 2026-07-28, 2025-11-25, 2025-06-18 and 2025-03-26 and answers with JSON (no SSE, no sessions).

Privacy

The server receives the tool name and its arguments (for example a string name or "comfort"), uses them to answer, and does not store them. It never sees your conversation or your account. Full policy: stringspec.com/privacy.

Support

Email g@bigballi.com, or see stringspec.com/connect.

License

The contents of this repository are released under the MIT License. The data served by the StringSpec MCP server is not part of this repository and is not covered by that license.

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