flipdot presents 9 well-named, verb-action tools with clear descriptions. Most parameters have type annotations and descriptions. However, output schemas are not explicitly documented in the source, several tools lack comprehensive parameter validation constraints, and error handling guidance is minimal. The server is well-structured for HTTP/FastMCP, with good naming conventions (get_*, set_*, list_*) and moderate parameter completeness.

• Add explicit output schemas to each tool definition showing the structure of returned data. E.g., get_display returns {image: bytes, ascii: string, mode: string, width: int, height: int}. Document in docstring or via FastMCP's return type annotations.
• Enumerate valid mode identifiers in set_mode's description or schema. Replace 'The mode identifier to switch to' with 'One of: [list KNOWN_MODES from code], or call list_modes() first to discover available modes.'
• Add enum or pattern constraints for add_text font/style/spacing parameters. Document allowed values: font in ['classic', ...], style in ['regular', 'bold', 'italic'], spacing in range [0, 10].
• Add parameter bounds documentation. E.g., add_text x and y must be 0-27 (28x28 grid); text length ≤ N chars; size ≥ 1.
• Document error cases and recovery in tool descriptions. E.g., set_mode: 'If the mode is not available, call list_modes() to see valid options.'
• Mark write operations (set_mode, set_sleep_settings, show_message, clear_board, add_text) with destructiveHint or idempotentHint in tool annotations so agents know whether retry is safe. Use FastMCP's tool_hint parameter.
• Add a discovery tool or update list_modes to return detailed info about each mode (e.g., whether it accepts drawing, text, etc.) so agents can plan multi-step interactions.
• Validate input early and return structured error responses. If add_text receives x=100 (out of bounds), return {error: 'x coordinate out of bounds', expected_range: '0-27', received: 100} instead of a generic 500 error.