playlists_get_focused_previous

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states a read operation ('Get'), implying it's likely non-destructive, but doesn't clarify if it requires specific permissions, what happens if no playlist is focused, or the return format (e.g., item details or error). This leaves significant gaps for a tool with zero annotation coverage.

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 a single, clear sentence with no wasted words, effectively front-loading the core purpose. It's appropriately sized for a simple tool with no parameters, making it highly efficient and easy to parse.

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 tool's simplicity (0 parameters, no output schema, no annotations), the description is minimally adequate. It states what the tool does but lacks details on behavioral aspects like error handling or return values. For a read operation with no structured data, it meets basic needs but could be more informative about context and usage.

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 input schema has 0 parameters with 100% coverage, so no parameter documentation is needed. The description doesn't add param details, which is appropriate here. A baseline of 4 is given as it doesn't need to compensate for any schema gaps, though it doesn't exceed expectations by providing extra context.

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 action ('Get') and target resource ('previous item in the focused playlist'), providing a specific verb+resource combination. However, it doesn't explicitly differentiate from similar sibling tools like 'playlists_get_focused_next' or 'playlists_get_focused', which might retrieve different playlist items or states.

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 offers no guidance on when to use this tool versus alternatives, such as 'playlists_get_focused_next' for the next item or 'playlists_get_focused' for the current focused playlist. It also doesn't mention prerequisites, like whether a playlist must be focused first, leaving usage context unclear.

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