IconSnag MCP demonstrates solid definition quality with clear naming conventions, comprehensive parameter schemas, and well-structured tool interfaces. All 5 tools follow verb_noun naming patterns (search_icons, get_icon_svg, get_icon_png, list_sources, list_tags). Tool descriptions are present and descriptive (ranging from 92-226 characters), exceeding the 10-char minimum. Parameter schemas use Zod validation with type definitions, min/max bounds, and optional flags. However, there are notable gaps: (1) No documented output schemas for any tool, LLMs cannot plan downstream calls without knowing return structure; (2) Error handling lacks recovery guidance, no actionable messages for edge cases like invalid source IDs or icon not found; (3) No tool annotations (readOnlyHint, idempotentHint) despite all tools being read-only operations; (4) Parameter descriptions in some tools (list_sources, list_tags) are minimal since inputs are empty, but tools lack guidance on discovery usage patterns.

• Document output schema for search_icons: return array of {id: string, name: string, source: string, tags: string[], svg_url: string, png_url: string}. Include field descriptions so LLMs know which fields to extract for downstream calls.
• Document output schema for get_icon_svg and get_icon_png: return {id: string, source: string, style: string, url: string, content?: string (if fetch_content=true), mime_type: string}. Enable chaining by including id and source in response.
• Document output schema for list_sources: return {sources: [{id: string, name: string, description: string, icon_count: number, license: string, url: string}]}. Let agents filter by license or size.
• Document output schema for list_tags: return {tags: [{name: string, description: string, icon_count: number}]}. Let agents guide users to available categories.
• Add readOnlyHint: true annotation to all 5 tools. Enables clients to optimize caching and parallelization for safe read-only operations.
• Replace example-based descriptions in search_icons 'source' parameter with an enum of all valid source IDs (lucide, phosphor, material-symbols, etc.). Update tag parameter to enum of valid tags from TAG_LIST.
• Enhance descriptions for list_sources and list_tags: 'Call this first to discover available icon sources and their metadata, then use the source ID in search_icons.' Include guidance on when agents should call these discovery tools.
• Add error handling guidance: 'If source not found, call list_sources() to see available sources.' Document which inputs can fail and what to do (retry with corrected values, alternative parameters, etc.).