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

Annotations already declare readOnlyHint=true and openWorldHint=false, but the description adds critical behavioral context: this is a public catalog with seeded actors, excludes user private actors, and returns specific fields (headshots, type, bio). This goes beyond the annotations and clarifies the tool's data scope and contents.

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 concise sentences front-load the core purpose, then provide exclusion criteria and a recommended workflow. Every sentence earns its place, with no fluff or repetition of schema/annotation data.

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 read-only listing tool, the description fully explains what the agent gets (public roster with headshots, type, bio), who it belongs to (public, no private actors), and how to proceed (call audition with actor_id). Even without an output schema, the expected return fields and usage flow are clear.

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 one optional parameter that is an empty object with no properties, effectively meaning no meaningful parameters. The description adds no parameter details, but none are needed since the schema fully defines the empty input. Per the rubric, 0 meaningful params baseline is 4, so this is appropriate.

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 starts with a specific verb+resource+scope: 'List only the public seeded LetMeActForYou casting roster with headshots, type, and bio.' It clearly distinguishes this from related tools by explicitly stating it never includes private actors, and points to my_actors for that, giving it unique purpose among siblings.

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?

Provides explicit usage guidance: 'Call this first, show the user the seed actors, then call audition with the chosen actor_id.' It also names the alternative tool for private actors ('authenticated users can retrieve those with my_actors'), telling the agent when not to use this tool.

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