LABSCO SUMMARY
The model tunes its own search width — that is the useful handle here.
beamWidth and numSimulations are exposed to the model, so how many paths to keep and how many simulations to run become part of the reasoning rather than fixed config. Be clear-eyed about the state of it: the alpha policy-simulation variants are described by the author as incomplete, and the benchmark section is a plan, not results.
What it is
A reasoning server for Claude Desktop that runs a problem through an explicit search strategy and reports on the paths it explored.
What you get
- Two search strategies you switch between: beam search, and Monte Carlo Tree Search for harder problems
- Two experimental MCTS variants added in v2.0.0 — mcts-002-alpha, which uses A* search with an early policy simulation layer, and mcts-002alt-alpha, which uses bidirectional search
- Scoring across reasoning paths, and a map of the different routes taken through a problem
- An analysis of how the reasoning process went
- Model control over the search parameters: beamWidth from 1 to 10, and numSimulations from 1 to 150
Requirements
Node and npm. Clone the repository, npm install, npm run build, then point Claude Desktop at dist/index.js. The alpha simulators are explicitly incomplete and subject to change; benchmarks against MATH500, GPQA-Diamond and others are listed as planned rather than published.
Setup effort
Build from source — git clone https://github.com/Jacck/mcp-reasoner.git
USE CASES
01
Working a problem with several plausible routes
Use beam search to keep more than one line alive rather than committing to the first.
02
Tackling something where the first approach usually fails
Switch to MCTS and let it explore before settling.
03
Trading depth against cost
Turn the beam width or simulation count up for the hard question and back down afterwards.
04
Seeing how an answer was reached
Read the map of explored paths and the analysis of the reasoning process.
BEFORE YOU INSTALL
What to know first
Requires
node on PATH
Where it runs
The documented client runs the server on your machine.
INSTALLATION
Connect your client
Server setup
TERMINAL
git clone https://github.com/Jacck/mcp-reasoner.git
cd mcp-reasoner
npm install
npm run buildMCP Clients
Claude Desktop
CLAUDE DESKTOP · JSON
{
"mcpServers": {
"mcp-reasoner": {
"command": "node",
"args": [
"<YOUR_PATH_TO_MCP_REASONER>/dist/index.js"
]
}
}
}