This is a minimal calculator server with two tools. Both tools have missing or inadequate descriptions, no parameter descriptions whatsoever, and while schemas are technically present via Zod, they lack required documentation. The server violates several critical patterns: parameter descriptions are entirely absent (100% missing), tool descriptions are vague and under 50 characters (far below the 194-char baseline), and there is no error handling guidance. The 'divide by zero' check returns a text error rather than a structured error response. Output schemas are implicit (text content) but never documented. This is well below community baseline and would not pass production code review.

• Expand tool descriptions to 50 - 200 characters. For 'add': 'Adds two numbers and returns their sum. Use this for simple binary addition. Returns a numeric result as text.' For 'calculate': 'Performs arithmetic operations (add, subtract, multiply, divide) on two numbers. Pass the operation and operands; returns numeric result or error message.'
• Add descriptions to every parameter. For 'a' and 'b': 'The first / second operand (a number)'. For 'operation': 'The arithmetic operation to perform: add, subtract, multiply, or divide.'
• Consolidate redundant tools: remove 'add' and make 'calculate' the primary tool, or document why both exist. If both are needed, name them distinctly (e.g., 'add_simple' vs 'calculate_advanced') with descriptions that make the choice obvious.
• Document output schema explicitly: 'Returns { content: [{ type: "text", text: "<numeric_result>" }] }'.
• Replace divide-by-zero error with structured error response: return { content: [{ type: "text", text: "Error: Cannot divide by zero. Choose non-zero b value and retry." }] } or, better, define a formal error type.
• Add parameter constraints to descriptions: 'operation must be one of: add, subtract, multiply, divide.'
• Consider adding simple examples in tool descriptions (but NOT in parameter descriptions): 'Example: add(2, 3) → 5'.