Create playlist / add tracks

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

With no annotations, the description provides behavioral traits: 'Does not delete or remove anything' and 'private by default' for create. It does not mention authentication, rate limits, or error handling, but these are not critical for a creation/append tool.

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?

Two sentences with no filler. The first sentence explains the two actions, the second states a negative behavioral trait. Front-loaded and efficient.

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 6 parameters, no output schema, and no annotations, the description covers the two modes and key parameters. It lacks return value details and error conditions, but provides enough for a typical use case.

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 83%, so baseline is 3. The description adds value by grouping parameters by action (e.g., 'name' for create, 'uris' for add_items) and specifying the default for 'public'. This clarifies usage beyond the schema.

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 two actions: 'action=create makes a new playlist' and 'action=add_items appends track URIs to an existing playlist'. It uses specific verbs (makes, appends) and resources (playlist, track URIs), and distinguishes from sibling tools like get_playlists or get_playlist_items.

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 implicitly guides usage by detailing the two actions and their parameters. It notes what the tool does not do ('Does not delete or remove anything'), but does not explicitly compare with alternatives or state when not to use this tool over siblings like library or search.

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