List my playlists

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

No annotations exist, so the description must convey behavior itself. It conveys the scope (user's playlists), the output (IDs), and the intended read/lookup use case, but it does not explicitly state that the call is read-only or describe limitations such as pagination or an empty playlist list.

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 states the result set and the second provides the decision rule. The usage guidance is front-loaded and easy for an agent to act on.

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 parameterless list operation, the description covers the key facts: what is returned (playlists with IDs) and when to use it (find an existing playlist by user-supplied name). It stops short of documenting the full response shape or explicitly labeling the operation as read-only, but these are minor omissions given the tool's simplicity.

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 tool has no parameters, making schema coverage vacuously complete. There is no parameter information that the description could add, so the baseline of 4 applies.

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 identifies the resource ('the user's playlists') and signals that IDs are part of the returned data. It also clarifies the tool's role as a lookup for an existing playlist to edit, distinguishing it from creating a new one, though it never uses an explicit verb like 'lists' or 'returns.'

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 a concrete trigger: call this when the user names a playlist they want to edit, as in 'add these to my Focus playlist.' It also supplies a when-not by saying 'instead of creating a new one,' which routes the agent away from create_playlist.

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