The server has 6 well-named tools with explicit descriptions and input schemas, but critical gaps prevent a higher score. All tools are registered via @mcp.tool() decorator with names, descriptions, and input schemas visible in main.py. However: (1) Output schemas are NOT documented, none of the tool docstrings specify what fields the returned JSON contains, forcing LLMs to infer structure; (2) several parameter descriptions are generic or incomplete (e.g., 'gates' parameter says 'List of gate operations, each with type and qubits keys' but doesn't specify which gate types, constraints, or what classical_bit means); (3) no error handling guidance, functions return bare error strings like 'Circuit not found' without actionable recovery instructions; (4) parameter descriptions lack detail on ranges, constraints, or formats (e.g., 'shots' has no guidance on min/max values, though typical values are 1 - 4096); (5) no documentation of which tools support pagination or limits. The naming is solid (verb-noun pattern), and core schemas are present, but incomplete parameter descriptions and missing output schemas prevent higher scores.

• Add explicit output schema documentation to every tool. For run_circuit, document: 'Returns a JSON object with keys: circuit (string), shots (integer), results (object mapping bit strings to counts), total_counts (integer).' Repeat for all 6 tools.
• Convert the 'gates' parameter in add_gates to enforce enum constraints. Replace the generic array-of-objects with a schema that specifies: gates = array of {type: enum[h|x|y|z|cx|measure|measure_all], qubits: array[integer], classical_bit?: integer}.
• Add min/max constraints to numeric parameters. Document: 'shots (int, 1 - 4096)', 'num_qubits (int, 1 - 20)', 'num_classical_bits (int, 0 - 20)'.
• Replace bare error strings with actionable recovery guidance. E.g., change 'Circuit not found' to 'Circuit not found. Call create_quantum_circuit first to create one.' Change 'Unsupported gate type' to 'Unsupported gate type: {gate_type}. Valid types are: h, x, y, z, cx, measure, measure_all.'
• Include circuit_name (or generated name) in the response of create_quantum_circuit as a structured field, not just in the success message. Return JSON: {name: string, qubits: integer, classical_bits: integer}.
• Add tool annotations via FastMCP. Use @mcp.tool(hints={'readOnly': True}) for get_circuit_info, run_circuit, visualize_circuit, visualize_circuit_mermaid; and @mcp.tool(hints={'destructive': True}) for create_quantum_circuit (creates persistent state), add_gates (mutates state).
• Document parameter relationships. In add_gates description: 'For single-qubit gates (h, x, y, z, measure), qubits must contain 1 element. For two-qubit gates (cx), qubits must contain 2 elements. classical_bit is required only for measure; ignored for other gates.'