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A client that connects LangChain to MCP (Model Context Protocol) servers, enabling LangChain agents to use tools exposed by MCP servers
This MCP server implements a single adapter tool that wraps MCP tools for LangChain consumption. The tool name 'McpToLangChainAdapter' is a noun (not verb-prefixed), making it unclear what action it performs. The description is generic and does not explain what the tool does, when to use it, or what it returns. No input schema is visible in the provided source code. The implementation is adapter-focused rather than tool-definition-focused, meaning it does not define concrete MCP tools with proper schemas and descriptions, it dynamically converts external MCP tools. This architectural approach means there are no statically-verifiable tool definitions to evaluate against the definition quality rubric. The visible code shows schema fixing logic (fix_schema function) for handling nullable types, but no explicit tool registration with proper input/output schemas is demonstrated.
Dynamic adapter that converts MCP tools to LangChain BaseTool format. Each MCP tool is wrapped and made available as a LangChain-compatible tool with async execution support.
Tool name does not start with an action verb. 'McpToLangChainAdapter' is a noun describing the implementation, not an action. Per pattern:tool, names must start with verbs like get_, create_, update_, delete_, search_, list_, send_. An LLM cannot infer what action this tool performs from the name alone.
No input schema visible in source code. The tool definition lacks JSON Schema with types and property descriptions. Per HARD SCORING RULE, schema score MUST be 0 when no schema is visible.
Description is generic and lacks actionable context. 'Dynamic adapter that converts MCP tools to LangChain BaseTool format...' does not explain WHAT the tool does (is it a registration function? A discovery tool? A conversion utility?), WHEN to call it (when would an LLM invoke this vs. other tools?), or WHAT it returns. Per pattern:tool-description, descriptions must answer: What? When? Why? Currently it only describes the implementation approach.
Inferred effective spec: <=2025-11-25.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-21 | F | 26 | <=2025-11-25 | v2 |
| 2026-03-09 | F | 28 | - | v1 |
Tool is an adapter that dynamically wraps external MCP tools, not a concrete tool definition. This architectural choice means there are no statically-verifiable tool schemas, parameter descriptions, or error handling patterns to evaluate. Per HARD SCORING RULE: 'If you cannot see the actual tool definition in the source (only inferred): cap that tool's overall at 50.' Here, tool existence and shape are entirely runtime-inferred from external MCP servers, not explicitly defined in this codebase.
No parameter descriptions visible. If this tool accepts parameters (e.g., which MCP server to connect to, which tool to wrap, configuration options), they are not documented in the visible code. Per pattern:tool-description, every parameter must have a non-empty description.
No output schema documented. It is unclear what structure this tool returns, what fields are available, or how downstream tools should interpret the result. Per pattern:tool, output schemas must be documented so LLMs can plan downstream actions.
Error handling approach not visible. The code shows no recovery guidance, error classification, or actionable error messages. Per pattern:recovery-guide, errors must tell the LLM what to do next.