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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds concrete traits beyond them: a daily quota shared with 60fps_get_motion_code and the fallback behavior that an unknown slug returns the closest matches. This is genuinely useful operational context that annotations do not convey.

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?

Front-loads the return anatomy, then usage/alternative, then the quota warning, ending with the error behavior. Every sentence carries distinct information with no redundancy.

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?

An output schema exists, so return-value detail is not strictly required, yet the description still summarizes the anatomy. Combined with usage routing, quota disclosure, and error behavior, an agent has everything needed to decide and invoke correctly.

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 100%, so the schema already documents both parameters; the baseline is 3. The description adds meaning to the slug parameter by disclosing that an unknown slug yields closest matches (fuzzy resolution), which is a semantic beyond the schema's 'The shot's slug'.

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?

States a specific verb (get) and resource (motion breakdown) and enumerates the exact contents returned: the gesture/trigger, motion behaviors, start→transition→end states plus rationale, and sampled keyframe images. It explicitly distinguishes itself from 60fps_get_shot ('to judge what a shot is, 60fps_get_shot is enough'), so an agent can pick it without opening any schema.

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?

Gives an explicit triggering condition ('after picking a shot, to understand or recreate how it moves') and names the alternative with the condition that selects it (60fps_get_shot for merely judging a shot). It also warns to call it only for shots you will actually use because of the shared daily limit.

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