create_smart_playlist

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and does well: it discloses that dry_run performs no creation, that saved_tracks truncation is reported, and that deprecated recommendations endpoints are not involved. It does not mention authentication/write scope or return format, but the key side-effect and edge-case behaviors are surfaced.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three dense sentences with no wasted words. The core purpose is front-loaded, followed by the most important behavioral caveats. Every sentence earns its place, and the structure is easy to scan.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 10-parameter tool with no output schema, the description covers the key behaviors and non-obvious interactions well. It explains the source pool, truncation, dry_run, and deprecated-endpoint note. It does not describe the return payload or explicitly state the write requirement, but the rich schema plus description is nearly complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3. The description adds meaningful cross-parameter semantics: how scan_cap interacts with saved_tracks (newest N, default fetchAllCap=500, truncation reporting), what dry_run does, and what the unique_artists toggle means. This goes beyond the individual schema descriptions without being redundant.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific action ('Create a playlist') on a specific resource ('from rules over your own listening data'), and enumerates concrete source types and options. It clearly distinguishes itself from generic playlist creation (create_playlist) and rule-saving tools (save_smart_playlist_rule) by emphasizing rule-based generation and dry_run semantics.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives clear context: use this when creating a playlist from personal listening data with rule-based selection. It explains the saved_tracks source behavior and dry_run preview, which guides safe invocation. However, it does not explicitly name alternative tools or state when not to use it, so it falls short of full exclusionary guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.