@modelcontextprotocol/server-sequential-thinking
MCPMCP server for sequential thinking and problem solving
Dimension scores
Compatibility
| Framework | Status | Notes |
|---|---|---|
| Claude Code | ✓ | — |
| OpenAI Agents SDK | ✓ | Zod schemas need translation to JSON Schema for OpenAI format, SSE transport not explicitly supported, only stdio |
| LangChain | ✓ | State management via SequentialThinkingServer instance may require careful wrapping, Stateful thoughtHistory tracking needs proper LangChain integration |
Reliability
Success rate
85%
Calls made
100
Avg latency
15ms
P95 latency
25ms
Failure modes
- • Missing required fields cause tool registration validation to fail before processThought is called
- • Invalid types (non-numeric thoughtNumber/totalThoughts) fail at Zod validation layer
- • Negative or zero thoughtNumber/totalThoughts fail Zod min(1) validation
- • Very large thoughtNumber values could cause memory issues in thoughtHistory array
- • Concurrent calls could cause race conditions in shared state (thoughtHistory, branches)
- • Process crash exits abruptly - index.ts has truncated error handler (process.ex)
- • No timeout protection - malicious inputs with extremely long strings could hang
- • No memory limits - unbounded thoughtHistory growth over many calls
- • Branch tracking uses Record without cleanup - potential memory leak
- • Error handling catches all errors but returns isError flag that may not be checked by SDK
- • No validation of branchId format or length
- • Console.error logging could fail in restricted environments
- • JSON.stringify could fail on circular references or very large objects
- • Chalk dependency could fail in non-TTY environments despite being optional
- • No graceful degradation if environment variables are malformed
Code health
License
SEE LICENSE IN LICENSE
Has tests
Yes
Has CI
No
Dependencies
3
Well-structured TypeScript project with good test coverage and documentation. Has tests using Vitest with coverage configuration. TypeScript with proper type definitions. Published to npm registry (@modelcontextprotocol/server-sequential-thinking@0.6.2). README is comprehensive (5399 bytes) with usage examples and configuration. However, missing CI configuration, no CHANGELOG, and license reference is non-standard. Cannot assess git activity as only source files provided. Dependencies are minimal (MCP SDK, chalk, yargs) which is good for maintenance. Test file shows good coverage of core functionality including edge cases and branching logic. Code quality appears high with proper separation of concerns (lib.ts for logic, index.ts for server setup). Missing: CI/CD pipeline, CHANGELOG for version tracking, standard license file.