The server provides 40 tools with complete schemas and consistent descriptions. All tools are explicitly registered with Zod schemas in site/app/mcp-lib/tools.ts. Most tool names follow verb_noun conventions (search_*, get_*, create_*, list_*, etc.). Descriptions are present and meaningful (average ~80-100 chars), though they could be more prescriptive about use cases and dependencies. Parameter schemas are well-typed with enums for constrained inputs (type fields). A significant strength is consistent tool annotation use (readOnlyHint, destructiveHint for risk classification). However, output schemas are not documented, responses are text-wrapped JSON without explicit field documentation. Error handling is minimal, no recovery guidance or retryability classification. Several related tools could be better composed (e.g., add_track/add_album → single batch variant). Some parameters lack dependency documentation (e.g., playlistUuid must exist before add_track is called).

• Document output schemas for every tool. Use JSDoc or explicit type definitions showing returned field names, types, and meaning. Example: '@returns {object} {id: string, name: string, tracks: Track[]}'
• Add pagination to list_* and search_* tools: limit (default 20, max 100), offset or cursor, and total_count in response. Cap result sets at 50-100 items.
• Replace generic error messages with actionable guidance: 'Token expired. Refresh and retry.' or 'Playlist not found. Check ID or call list_playlists() to find the right playlist.'
• Document parameter dependencies in descriptions. Example: playlistUuid → 'Must exist; call playlist_list() to find or create first.'
• Add idempotency keys or deduplication logic to write operations. Playlist_create could accept an optional idempotency_key and return the same ID if called twice.
• Create batch variants: batch_add_to_playlist(playlistUuid, items: [{type, id}]) instead of individual add_track/add_album calls.
• Expand descriptions with use-case clarity. Example: 'Get top tracks for an artist (for intro/discovery). See similar_tracks for variations on a single track, or track_radio for algorithmic mixes.'
• Add explicit readOnlyHint, destructiveHint, and idempotentHint annotations to all tools. Currently present but ensure consistency.
• Validate token format and scope before using it. Log who called what for audit trails.
• Consider adding a confirm_action tool or pattern for destructive operations (delete_playlist, clear_search_history) to match pattern:confirmation-request.

Inferred effective spec: <=2025-11-25.

• Relies on Dynamic Client Registration (deprecated) - use Client ID Metadata Documents (CIMD)