Create a smart (self-updating) playlist

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

The description discloses that Navidrome continuously re-evaluates rules, so playlists stay current without regeneration. It also reveals a key limitation: rules operate only on Navidrome's own fields, not ListenBrainz or Last.fm. With no annotations provided, this carries the full burden well, though it omits return values or error behavior.

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?

The description is dense but well-structured, opening with a clear purpose, then a concrete example, followed by operator/field lists and a limitations note. It is long, but every section earns its place given the complexity of the rules parameter.

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?

Given the complex nested rules object and no annotations/output schema, the description covers the critical aspects: rule syntax, operators, fields, and unsupported data. It could add what the API returns or error scenarios, but it is largely complete for invoking the tool correctly.

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?

The description provides an extensive explanation of the rules parameter, including a JSON example, a list of all operators, combinators (all/any), nesting, and available fields. This goes far beyond the schema's generic 'criteria object' description and fully compensates for the low schema coverage of other parameters.

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 clearly states the tool 'Create a playlist defined by RULES rather than a fixed track list', distinguishing it from the sibling create_playlist. It also provides a concrete use case ('90s rock I haven't played in a year') and emphasizes the self-updating behavior.

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?

It explicitly positions the tool for standing/self-updating playlists with an example, and explicitly directs users to search_tracks plus create_playlist when ListenBrainz/Last.fm fields are needed. The contrast with fixed track lists is clear, giving both when-to-use and when-not-to-use context.

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