This repository is for exploring an MCP (Model Context Protocol) server implementation using Node.js and TypeScript.
This server has 3 tools with basic definitions. Naming is mostly verb-based and clear, but descriptions vary in quality. Schemas are present but lack some clarity. The 'create-random-user' tool has no input parameters in its schema registration despite accepting none, which is correct but unusual. Annotations are present for all tools, which is a positive signal. However, parameter descriptions are minimal, and the error handling in responses is generic.
Create a random user with fake data
Create a new user in the database
An example tool that echoes back the input
Parameter descriptions lack format/validation guidance. Example: 'User's email' does not specify email format validation, accepted patterns, or length constraints.
Output schemas are not documented. Tools return text responses in ToolResultTextContent but do not specify expected structure for downstream tool chaining.
create-random-user relies on server-initiated sampling/createMessage (deprecated pattern). This invokes the host's LLM indirectly, which is not documented and violates the stateless request pattern.
Error handling is generic. Responses like 'Failed to save a user: <errorMessage>' do not guide the LLM on recovery steps or categorize errors as retryable/user-fixable.
Inferred effective spec: <=2025-11-25.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-22 | F | 48 | <=2025-11-25 | v2 |
| 2026-03-09 | F | 37 | - | v1 |
Destructive operations (create-user, create-random-user) do not have destructiveHint set correctly. Both perform WRITE operations but destructiveHint=false may mislead the LLM.
No rate limiting or permission gates on write operations. An agent could create thousands of users without authorization checks or rate throttling.