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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds value by stating 'No user account required,' which is a significant behavioral trait not captured in annotations, and by specifying 'active' artists, implying filtering behavior. These additions go beyond what annotations provide.

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 short sentences with no filler. The main action is front-loaded, and the additional note about account requirements is separate and succinct. Everything earns its place.

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 zero-parameter, read-only list tool, the description is nearly complete. It states what is listed and that no account is required. It does not describe the output shape, but with no output schema and a straightforward list resource, this is a minor gap; mentioning that returned artist IDs could be used with get_artist_details or create_song_generation would improve completeness.

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 zero parameters, so the baseline is 4 per the rubric. The description doesn't need to explain parameters, and it adds appropriate context (active, cowriters) that helps the agent understand what the returned list represents.

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 ('List'), the resource ('active SoundBreak AI artists (cowriters)'), and the intended purpose ('available for co-writing'). It distinguishes itself from sibling get_artist_details by emphasizing it returns a list of available artists rather than details for one artist.

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 provides clear context on when to use this tool: to find active AI artists for co-writing. It also mentions 'No user account required,' which sets an expectation about accessibility. However, it does not explicitly mention alternatives or exclusions, such as using get_artist_details for specific artist information, so it falls slightly short of a 5.

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