Sequential Thinking

What it is

Sequential Thinking is an MCP server that provides a single tool, sequential_thinking, for dynamic and reflective problem-solving through a structured thinking process. It lets a model break complex problems into steps, revise earlier thoughts, branch into alternative reasoning paths, and adjust the total number of thoughts as it goes. It is published on npm as @modelcontextprotocol/server-sequential-thinking.

Who it's for

• Developers using MCP-aware hosts (Claude Desktop, VS Code, Codex CLI) who want structured multi-step reasoning
• Users tackling complex planning, design, or analysis tasks that may need course correction
• Those working on problems whose full scope is unclear at the start

Requirements

Setup

1. Claude Desktop with npx

   Add this to your claude_desktop_config.json.

   jsonCopy

   {
     "mcpServers": {
       "sequential-thinking": {
         "command": "npx",
         "args": [
           "-y",
           "@modelcontextprotocol/server-sequential-thinking"
         ]
       }
     }
   }

2. Claude Desktop with Docker

   Run the server from the mcp/sequentialthinking Docker image. To disable logging of thought information, set the env var DISABLE_THOUGHT_LOGGING to true.

   jsonCopy

   {
     "mcpServers": {
       "sequentialthinking": {
         "command": "docker",
         "args": [
           "run",
           "--rm",
           "-i",
           "mcp/sequentialthinking"
         ]
       }
     }
   }

3. VS Code with npx

   Add to your user mcp.json (via the Command Palette: MCP: Open User Configuration) or to .vscode/mcp.json in your workspace.

   jsonCopy

   {
     "servers": {
       "sequential-thinking": {
         "command": "npx",
         "args": [
           "-y",
           "@modelcontextprotocol/server-sequential-thinking"
         ]
       }
     }
   }

4. Codex CLI

   Add the server with the codex mcp add command.

   bashCopy

   codex mcp add sequential-thinking npx -y @modelcontextprotocol/server-sequential-thinking

5. Build the Docker image

   Build the image locally from the repository.

   bashCopy

   docker build -t mcp/sequentialthinking -f src/sequentialthinking/Dockerfile .

Examples

Plan a database migration from PostgreSQL 14 to 16, list risks, and revise the plan if downtime exceeds 5 minutes.

Debug why this deployment only fails in production and show your reasoning step by step.

Compare three architecture options for a file sync engine and branch if one assumption turns out to be wrong.

{
  "mcpServers": {
    "sequential-thinking": {
      "command": "cmd",
      "args": [
        "/c",
        "npx",
        "-y",
        "@modelcontextprotocol/server-sequential-thinking"
      ]
    }
  }
}

Pros & cons

Images