Groundlink

Groundlink MCP Server

Use Groundlink's cited web-search results from any Model Context Protocol (MCP) host. The server exposes one focused tool, groundlink_search, which sends a query to Groundlink and returns source-bearing results (title, url, snippet, and source) for the model to use when it needs evidence rather than a guess.

Groundlink currently combines Wikipedia and DuckDuckGo results. Each Groundlink API key includes 100 free test queries; after that, prepaid usage is $0.001 per query (one credit per query).

Package: [email protected] is published on npm. Source: https://github.com/ohhavefun/groundlink

• Live API documentation: https://9ea69cec60fa01f65bbb647a092bcbb4.ctonew.app/docs
• Pricing and credits: https://9ea69cec60fa01f65bbb647a092bcbb4.ctonew.app/pricing

This repository is the home of Groundlink's official developer integrations. There are two, both maintained here:

Integration	What it is	Install
groundlink-mcp (MCP server)	Exposes Groundlink to any MCP host (Claude, Cursor, …)	npm install -g groundlink-mcp (also on the official MCP registry as io.github.ohhavefun/groundlink)
langchain-groundlink (Python/LangChain)	A GroundlinkSearchTool for Python agents	pip install "langchain-groundlink @ git+https://github.com/ohhavefun/groundlink#subdirectory=langchain-groundlink"

Both use the same free trial keys (100 queries) from the Groundlink onboarding, then prepaid usage at $0.001/query.

Where Groundlink is listed

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langchain-groundlink (Python / LangChain)

Use Groundlink's cited search from any Python agent or BaseTool pipeline. The tool returns source-bearing results (title, url, snippet, source) so your agent answers from evidence and can cite it.

Install from GitHub (the package is intentionally not on PyPI):

pip install "langchain-groundlink @ git+https://github.com/ohhavefun/groundlink#subdirectory=langchain-groundlink"

Quick usage (10 seconds): get a free key from the docs, then:

from langchain_groundlink import GroundlinkSearchTool

tool = GroundlinkSearchTool(api_key="glk_your_trial_key")  # or export GROUNDLINK_API_KEY
result = tool.invoke({"query": "Who was Ada Lovelace?"})
print(result)

Full usage, configuration, and error handling are in langchain-groundlink/README.md.

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Groundlink MCP Server

Use Groundlink's cited web-search results from any Model Context Protocol (MCP) host below.

Field	Value
Tool name	groundlink_search
Input	{ query: string, max_results?: number }
max_results	1–10; default 5 (or GROUNDLINK_MAX_RESULTS)
Output	JSON: { query, results: [{ title, url, snippet, source }], meta }

Use it for factual questions where the host should return URLs/sources with its answer. The MCP server is deliberately thin: it forwards the query to the Groundlink HTTPS API and returns the API response over MCP stdio.

Install and run

You need a Groundlink API key (glk_...). Ask the Groundlink operator for one or obtain one through the Groundlink onboarding flow.

npm install -g groundlink-mcp
export GROUNDLINK_API_KEY=glk_your_key_here
groundlink-mcp

Alternatively, an MCP host can execute the package without a global install:

npx -y groundlink-mcp

The process uses stdio; it does not open an HTTP port or print normal output to stdout. MCP hosts should launch it rather than running it interactively.

Configuration

Variable	Required	Default	Meaning
GROUNDLINK_API_KEY	Yes	—	API key used for every Groundlink request.
GROUNDLINK_BASE_URL	No	Groundlink live URL	Override only for a compatible deployment.
GROUNDLINK_MAX_RESULTS	No	5	Default results per tool call; capped at 10.

Claude Desktop configuration

Add this entry to Claude Desktop's MCP configuration file and restart Claude Desktop. Keep the API key private: do not commit it to a repository or share the configuration file.

{
  "mcpServers": {
    "groundlink": {
      "command": "npx",
      "args": ["-y", "groundlink-mcp"],
      "env": {
        "GROUNDLINK_API_KEY": "glk_your_key_here"
      }
    }
  }
}

If the package is installed globally, use "command": "groundlink-mcp" and omit args. For hosts that need an absolute executable path, point command at the installed groundlink-mcp binary.

What happens on errors

• Missing GROUNDLINK_API_KEY: the server exits at startup with a clear setup error.
• API key rejected (401): returned to the MCP host as a tool error; correct the key rather than retrying.
• No remaining free or prepaid credits (402): returned as a tool error; fund the key before another search.
• Search-source outage (502): returned as a tool error; a short retry may help.

Marketplace description

Groundlink — cited web search for MCP. Give Claude, Cursor, and other MCP hosts one groundlink_search tool that returns source-bearing results instead of unsupported factual guesses. Every key starts with 100 free tests, then usage is $0.001 per query through prepaid credits.

Development and release checks

bun install
bun run typecheck
bun run build             # emits executable dist/index.js
bun run test              # MCP stdio smoke test
npm run pack:check        # inspect the npm tarball without publishing

The npm package intentionally ships only the compiled dist/ runtime, this README, and npm's required package metadata. Source and smoke tests stay out of the tarball.