Single tool with acceptable naming and moderate schema definition. Description is present but generic (194 chars, at baseline). Tool name 'search_photos' correctly starts with verb. Input schema is well-formed with types and reasonable defaults. However, parameter descriptions are minimal and some quality gaps exist: no error handling guidance, no output structure documented beyond docstring, color/orientation enums listed inline in description rather than as constrained schema, parameter relationships underdocumented, no pagination explicit in return type, and API key management via environment is correct but not mentioned in security context.

• Convert color and orientation parameters from inline enum lists in description to formal JSON Schema enum fields: {"type": "string", "enum": ["black_and_white", "black", "white", ...]}
• Add formal JSON Schema output schema to tool definition (not just docstring). Document that response is List[UnsplashPhoto] with structure {id: string, description: string|null, urls: {raw, full, regular, small, thumb}, width: int, height: int}
• Add explicit per_page limit enforcement with feedback: if per_page > 30, cap at 30 and log warning so LLM sees it was adjusted.
• Add pagination metadata to response: wrap results in {items: [UnsplashPhoto], total_count: int, page: int, per_page: int, has_more: bool} so LLM can plan multi-page retrieval without guessing.
• Enhance docstring with error recovery paths: document HTTP 401 (invalid API key), 403 (rate limit), 400 (invalid params), timeout, and what the LLM should do in each case.
• Convert order_by to enum constraint: {"type": "string", "enum": ["relevant", "latest"], "default": "relevant"}
• Replace union type (integer|string) on page and per_page with proper integer type and explicit minimum/maximum constraints in schema.
• Add tool annotation hints: mark as read-only (readOnlyHint) since it only searches, never modifies state.