statsfm_now_playing

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

No annotations are provided, so the description carries the full burden. It does not explicitly state that this is a read-only operation or disclose any potential side effects, errors, or authorization requirements. The only behavioral detail is the null return when idle, which is insufficient for full transparency.

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, concise sentence that immediately conveys the tool's purpose. There is no extraneous information or unnecessary length, making it highly efficient for quick comprehension.

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 simple now-playing lookup, the description provides enough context: it tells what the tool does and the idle case. However, it could be more complete by explicitly noting that it queries the stats.fm service (already evident from the name) or by mentioning any rate limits or required user consent.

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 already includes descriptions for both parameters (user_id and response_format). The tool description adds no additional meaning beyond what the schema provides, earning the baseline score.

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's function: retrieving what a stats.fm user is currently playing. The inclusion of 'null when idle' adds important specificity about the return value, making the purpose unmistakable.

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?

There is no guidance on when to use this tool over the many similar siblings (e.g., get_now_playing, get_currently_playing). The description does not mention any differentiating conditions or preferences, leaving the selection decision to the agent without hints.

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