get_tracks_by_key

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

No annotations are provided, so the description must bear the full burden. It discloses the return type ('List of tracks') and gives the key format example, but it does not mention potential performance considerations, pagination, ordering, or behavior on invalid keys. For a simple read tool this is adequate but not rich.

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 short and front-loaded with the main purpose. It uses a clear Args/Returns structure. However, the Returns line largely restates the first sentence ('List of tracks in the specified key'), which is slightly redundant, so it doesn't earn a perfect 5.

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 (one parameter, no nested objects) and the presence of an output schema, the description is nearly complete. It explains the key input and the return type. Missing details like sort order or limit are minor for a simple getter tool, so this is above average.

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 description coverage is 0%, so the description must compensate. It does by explaining the 'key' parameter with a format hint and examples ('5A', '12B'), which adds meaning beyond the bare schema property type 'string'. This is valuable for a one-parameter tool.

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 uses a specific verb and resource: 'Get all tracks in a specific musical key.' This clearly distinguishes it from sibling tools like get_tracks_by_bpm_range, search_tracks, or get_playlists by naming the exact filtering criterion (musical key).

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 implies its use case: when you need tracks filtered by a musical key. However, it does not explicitly state when to use this tool versus alternatives, nor does it provide exclusions or mention sibling tools like search_tracks for broader queries. It relies on the name and description to convey context.

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