servers/src/sequentialthinking/index.ts
adam jones 88a2ac4360
fix(sequential-thinking): convert to modern TypeScript SDK APIs (#3014)
* fix(sequential-thinking): convert to modern TypeScript SDK APIs

Convert the sequential-thinking server to use the modern McpServer API
instead of the low-level Server API.

Key changes:
- Replace Server with McpServer from @modelcontextprotocol/sdk/server/mcp.js
- Use registerTool() method instead of manual request handlers
- Use Zod schemas directly in inputSchema/outputSchema
- Add structuredContent to tool responses
- Fix type literals to use 'as const' assertions

The modern API provides:
- Less boilerplate code
- Better type safety with Zod
- More declarative tool registration
- Cleaner, more maintainable code

* fix: exclude test files from TypeScript build

Add exclude for test files and vitest.config.ts to tsconfig

* refactor: remove redundant validation now handled by Zod

Zod schema already validates all required fields and types. Removed
validateThoughtData() method and kept only business logic validation
(adjusting totalThoughts if needed).

* fix(sequentialthinking): add Zod validation to processThought method

The modern API migration removed manual validation from processThought(),
but tests call this method directly, bypassing the Zod validation in the
tool registration layer. This commit adds Zod validation directly in the
processThought() method to ensure validation works both when called via
MCP and when called directly (e.g., in tests).

Also improves error message formatting to match the expected error
messages in the tests.

* refactor: simplify by removing redundant validation

Since processThought() is only called through the tool registration in
production, validation always happens via Zod schemas at that layer.
Removed redundant validation logic from processThought() and updated
tests to reflect this architectural decision.

Changes:
- Remove Zod validation from processThought() method
- Accept ThoughtData type instead of unknown
- Remove 10 validation tests that are now handled at tool registration
- Add comment explaining validation approach
2025-11-20 19:05:30 +00:00

118 lines
4.9 KiB
JavaScript

#!/usr/bin/env node
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { z } from "zod";
import { SequentialThinkingServer } from './lib.js';
const server = new McpServer({
name: "sequential-thinking-server",
version: "0.2.0",
});
const thinkingServer = new SequentialThinkingServer();
server.registerTool(
"sequentialthinking",
{
title: "Sequential Thinking",
description: `A detailed tool for dynamic and reflective problem-solving through thoughts.
This tool helps analyze problems through a flexible thinking process that can adapt and evolve.
Each thought can build on, question, or revise previous insights as understanding deepens.
When to use this tool:
- Breaking down complex problems into steps
- Planning and design with room for revision
- Analysis that might need course correction
- Problems where the full scope might not be clear initially
- Problems that require a multi-step solution
- Tasks that need to maintain context over multiple steps
- Situations where irrelevant information needs to be filtered out
Key features:
- You can adjust total_thoughts up or down as you progress
- You can question or revise previous thoughts
- You can add more thoughts even after reaching what seemed like the end
- You can express uncertainty and explore alternative approaches
- Not every thought needs to build linearly - you can branch or backtrack
- Generates a solution hypothesis
- Verifies the hypothesis based on the Chain of Thought steps
- Repeats the process until satisfied
- Provides a correct answer
Parameters explained:
- thought: Your current thinking step, which can include:
* Regular analytical steps
* Revisions of previous thoughts
* Questions about previous decisions
* Realizations about needing more analysis
* Changes in approach
* Hypothesis generation
* Hypothesis verification
- nextThoughtNeeded: True if you need more thinking, even if at what seemed like the end
- thoughtNumber: Current number in sequence (can go beyond initial total if needed)
- totalThoughts: Current estimate of thoughts needed (can be adjusted up/down)
- isRevision: A boolean indicating if this thought revises previous thinking
- revisesThought: If is_revision is true, which thought number is being reconsidered
- branchFromThought: If branching, which thought number is the branching point
- branchId: Identifier for the current branch (if any)
- needsMoreThoughts: If reaching end but realizing more thoughts needed
You should:
1. Start with an initial estimate of needed thoughts, but be ready to adjust
2. Feel free to question or revise previous thoughts
3. Don't hesitate to add more thoughts if needed, even at the "end"
4. Express uncertainty when present
5. Mark thoughts that revise previous thinking or branch into new paths
6. Ignore information that is irrelevant to the current step
7. Generate a solution hypothesis when appropriate
8. Verify the hypothesis based on the Chain of Thought steps
9. Repeat the process until satisfied with the solution
10. Provide a single, ideally correct answer as the final output
11. Only set next_thought_needed to false when truly done and a satisfactory answer is reached`,
inputSchema: {
thought: z.string().describe("Your current thinking step"),
nextThoughtNeeded: z.boolean().describe("Whether another thought step is needed"),
thoughtNumber: z.number().int().min(1).describe("Current thought number (numeric value, e.g., 1, 2, 3)"),
totalThoughts: z.number().int().min(1).describe("Estimated total thoughts needed (numeric value, e.g., 5, 10)"),
isRevision: z.boolean().optional().describe("Whether this revises previous thinking"),
revisesThought: z.number().int().min(1).optional().describe("Which thought is being reconsidered"),
branchFromThought: z.number().int().min(1).optional().describe("Branching point thought number"),
branchId: z.string().optional().describe("Branch identifier"),
needsMoreThoughts: z.boolean().optional().describe("If more thoughts are needed")
},
outputSchema: {
thoughtNumber: z.number(),
totalThoughts: z.number(),
nextThoughtNeeded: z.boolean(),
branches: z.array(z.string()),
thoughtHistoryLength: z.number()
},
},
async (args) => {
const result = thinkingServer.processThought(args);
if (result.isError) {
return result;
}
// Parse the JSON response to get structured content
const parsedContent = JSON.parse(result.content[0].text);
return {
content: result.content,
structuredContent: parsedContent
};
}
);
async function runServer() {
const transport = new StdioServerTransport();
await server.connect(transport);
console.error("Sequential Thinking MCP Server running on stdio");
}
runServer().catch((error) => {
console.error("Fatal error running server:", error);
process.exit(1);
});