This server has 3 tools with basic schemas and descriptions, but significant gaps prevent higher scoring. Tool names follow verb_noun pattern (show_diagram, get_diagram_feedback, close_diagram), which is good. However, descriptions lack LLM-optimized specificity, parameter descriptions are minimal, and output schemas are not documented. The server operates in STDIO mode, which impacts overall scoring. Descriptions exist but are between 100-200 chars, meeting minimum bars but lacking the precision expected in production tools. No parameter validation guidance, error classification, or recovery hints provided.

• Document the output schema for each tool. For show_diagram, specify: {success: boolean, url: string, editor_connected: boolean, message: string}. For get_diagram_feedback, specify: {status: 'pending'|'submitted'|'error', mermaid_code?: string, changes_summary?: string, message?: string}.
• Add parameter validation rules to show_diagram.mermaid_code: 'Valid Mermaid flowchart syntax (must start with "graph" or "flowchart"; see mermaid.js.org for syntax). Typical length: 100 - 5000 chars.'
• Replace example values in descriptions with enum/pattern constraints. Change 'Mermaid flowchart code (e.g., "graph TD...")' to 'Mermaid flowchart syntax conforming to https://mermaid.js.org/syntax/flowchart.html'.
• Add explicit error guidance to get_diagram_feedback: 'Returns status="error" with message "No active diagram session" if show_diagram has not been called or close_diagram was called. In this case, call show_diagram first.'
• Document polling semantics: 'Poll repeatedly until status is "submitted" or "error". Results are cleared after reading, a second poll will return status="pending". Typical polling interval: 1 - 5 seconds.'
• Add sidedness declarations: 'show_diagram opens a browser editor (side effect); agent may call once per session. get_diagram_feedback is read-only and idempotent. close_diagram shuts down the editor (idempotent; safe to call multiple times).'
• Add optional 'timeout' parameter to get_diagram_feedback to limit polling duration, e.g. timeout_seconds: 300. This prevents indefinite blocking.