brainstorm-mcp

An MCP server that runs multi-round brainstorming debates between AI models. Connect it to Claude Code (or any MCP client) and let GPT, Gemini, DeepSeek, Groq, Ollama, and others debate your ideas — with Claude as an active participant in every round.

No more single-perspective answers. brainstorm-mcp pits multiple LLMs against each other so you get diverse viewpoints, critiques, and a consolidated synthesis.

Features

• Claude as participant — Claude debates alongside external models, bringing full conversation context
• Multi-round debates — Models see and critique each other's responses across rounds
• Parallel execution — All models respond concurrently within each round
• Per-model timeouts — 2-minute timeout per API call, one slow model won't block others
• Context truncation — Automatically truncates history when approaching context limits
• Cost estimation — Shows estimated token usage and cost per debate
• Resilient — One model failing doesn't abort the debate
• Synthesizer fallback — If the primary synthesizer fails, tries other models
• Session management — Interactive sessions with 10-minute TTL, automatic cleanup
• GPT-5.x / o3 / o4 compatible — Automatically uses max_completion_tokens for newer OpenAI models
• Cross-platform — Works on macOS, Windows, and Linux

How It Works

1. You ask Claude: "Brainstorm the best architecture for a real-time app"
2. The tool sends the topic to all configured AI models in parallel (Round 1)
3. Claude reads their responses and contributes its own perspective
4. All models (including Claude) see each other's responses and refine their positions (Rounds 2-N)
5. A synthesizer model produces a final consolidated output
6. You get back a structured debate with the synthesis

Claude doesn't just orchestrate — it debates alongside GPT, Gemini, DeepSeek, and others.

Quick Start

With Claude Code

Add to your project's .mcp.json:

{
  "mcpServers": {
    "brainstorm": {
      "command": "npx",
      "args": ["-y", "brainstorm-mcp"],
      "env": {
        "OPENAI_API_KEY": "sk-...",
        "DEEPSEEK_API_KEY": "sk-..."
      }
    }
  }
}

With Claude Desktop

Add to your Claude Desktop config (claude_desktop_config.json):

{
  "mcpServers": {
    "brainstorm": {
      "command": "npx",
      "args": ["-y", "brainstorm-mcp"],
      "env": {
        "OPENAI_API_KEY": "sk-...",
        "DEEPSEEK_API_KEY": "sk-..."
      }
    }
  }
}

Manual install

npm install -g brainstorm-mcp
brainstorm-mcp

Then just ask Claude:

"Brainstorm the best way to handle authentication in a microservices architecture"

Interactive Mode (Claude as Participant)

By default, Claude actively participates in every round of the debate:

1. Round 1: External models respond to the topic independently
2. Claude's turn: Claude reads their responses and contributes its own perspective via brainstorm_respond
3. Round 2: External models see Claude's response alongside everyone else's, and refine
4. Claude's turn: Claude refines its position based on the new responses
5. Repeat until all rounds are complete, then synthesis runs automatically

This means Claude brings its full conversation context into the debate — it knows what you've been working on, what you've discussed, and can contribute meaningfully rather than just passing messages.

To run a non-interactive debate (external models only, no Claude participation):

"Brainstorm with participate=false about..."

Configuration

Option 1: Environment Variables (simplest)

Just set API keys as env vars — the server auto-detects providers:

OPENAI_API_KEY=sk-...
OPENAI_DEFAULT_MODEL=gpt-4o
GEMINI_API_KEY=AIza...
GEMINI_DEFAULT_MODEL=gemini-2.5-flash
DEEPSEEK_API_KEY=sk-...
DEEPSEEK_DEFAULT_MODEL=deepseek-chat
GROQ_API_KEY=gsk_...

Option 2: Config File (full control)

Set BRAINSTORM_CONFIG to point to a JSON config file:

{
  "providers": {
    "openai": {
      "model": "gpt-4o",
      "apiKeyEnv": "OPENAI_API_KEY"
    },
    "gemini": {
      "model": "gemini-2.5-flash",
      "apiKeyEnv": "GEMINI_API_KEY"
    },
    "deepseek": {
      "model": "deepseek-chat",
      "apiKeyEnv": "DEEPSEEK_API_KEY"
    },
    "groq": {
      "model": "llama-3.3-70b-versatile",
      "apiKeyEnv": "GROQ_API_KEY"
    },
    "ollama": {
      "model": "llama3.1",
      "baseURL": "http://localhost:11434/v1"
    }
  }
}

Known providers (openai, gemini, deepseek, groq, mistral, together) don't need a baseURL — it's auto-detected.

| Field | Required | Description | |-------|----------|-------------| | model | Yes | Default model ID to use | | apiKeyEnv | No | Environment variable name for the API key. Omit for local models (Ollama) | | baseURL | No | API endpoint. Auto-detected for known providers |

Tools

| Tool | Description | |------|-------------| | brainstorm | Run a multi-round debate between configured AI models | | brainstorm_respond | Submit Claude's response for the current round of an interactive session | | list_providers | Show all configured providers, models, and API key status | | add_provider | Dynamically add a provider at runtime |

brainstorm Parameters

| Parameter | Type | Default | Description | |-----------|------|---------|-------------| | topic | string | required | What to brainstorm about | | models | string[] | all providers | Specific models as provider:model | | rounds | number | 3 | Number of debate rounds (1-10) | | synthesizer | string | first model | Model for final synthesis | | systemPrompt | string | — | Custom system prompt for all models | | participate | boolean | true | Whether Claude joins as an active debater |

brainstorm_respond Parameters

| Parameter | Type | Description | |-----------|------|-------------| | session_id | string | Session ID from the brainstorm tool | | response | string | Claude's contribution (min 50 chars) |

Usage Examples

Basic brainstorm

"Brainstorm the pros and cons of microservices vs monolith for a startup"

Targeted models

"Use brainstorm with models openai:gpt-4o and deepseek:deepseek-chat to debate whether React or Vue is better for enterprise apps"

Deep dive with more rounds

"Brainstorm with 5 rounds: what's the best database strategy for a social media app with 10M users?"

Privacy Policy

brainstorm-mcp itself does not collect any user data. It acts as a proxy to the AI providers you configure. Your prompts and debate content are sent to the respective provider APIs (OpenAI, DeepSeek, Groq, etc.) according to their privacy policies. For local models (Ollama), all data stays on your machine.

Development

git clone https://github.com/spranab/brainstorm-mcp.git
cd brainstorm-mcp
npm install
npm run build
npm start

Support

• Issues: https://github.com/spranab/brainstorm-mcp/issues
• Repository: https://github.com/spranab/brainstorm-mcp

License

MIT