YouTube MCP server has 8 well-named tools with consistent verb_noun patterns (search_*, get_*, all starting with action verbs). All tools have descriptions (avg ~120 chars, within baseline 34-392 range). Input schemas are present with type definitions and parameter descriptions. However, output schemas are NOT documented, tools return JSON strings but the structure of returned objects is not formally specified. Error handling is present but generic; some tools return helpful context (e.g., IP blocking, transcript unavailable) but lack recovery guidance. No tool annotations (readOnlyHint, destructiveHint, idempotentHint). Parameter descriptions are adequate but could be more prescriptive about constraints (e.g., 'limit' lacks explicit min/max in descriptions, only enforced in code). No pagination support documented despite tools accepting 'limit' parameters.

• Document output schemas for all tools. Specify the structure of returned JSON objects, including field names, types, and nested objects. Example: 'Returns array of {url: string, title: string, views: integer, published_at: ISO8601}'.
• Add explicit min/max bounds to parameter descriptions. Change 'Maximum number of results (default 10, max 30)' to 'Maximum number of results. Range: 1 - 30 (default 10). Values above 30 are capped.'
• Add readOnlyHint annotation to all tools in fastmcp registration. All 8 tools are read-only; declaring this enables agents to distinguish them from destructive operations.
• Enhance error messages with recovery guidance. Instead of 'Failed to get video info: {e}', return 'Video not found. Verify the URL is correct (format: https://youtube.com/watch?v=...) or try search_videos() to find the video.'
• Document pagination behavior. Add to tool descriptions: 'Results are limited to {limit} items. For larger datasets, call the tool multiple times with different search queries or channel handles.'