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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), yet the description still adds real behavior: failure semantics (a failed slide was refunded), the polling cadence, and that omitted slides are static images. It stops short of error/edge-case handling, but the added context is meaningful.

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?

Dense but efficient: return fields, status meanings, polling instruction, and scope boundary are all packed into a few clauses with the primary payload front-loaded. Slightly clause-heavy, but no sentence is wasted.

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?

No output schema exists, and the description compensates by naming the returned fields and their meanings, plus the polling loop and the sibling that holds full data. Only error behavior and how partial/missing slides should be reported back are unaddressed.

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 coverage is 100% with both parameters documented (job_id as the carousel job id, user_goal as optional free-text context). The description only indirectly clarifies that job_id refers to the job animate_carousel produced and says nothing about user_goal, so it stays at baseline 3.

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 concrete verb+resource: per-slide status, video_url, and poster_url for a carousel that animate_carousel started, with enumerated status values (rendering/ready/failed). It also explicitly separates itself from siblings: 'Slides not listed are still pictures; get_job has the whole deck.' An agent can select it without opening a 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 actionable polling guidance ('While rendering is true, poll again in ~30s') and points to get_job as the alternative for the full deck. The trigger for calling it at all (after animate_carousel started) is implied by phrasing rather than stated as an explicit precondition.

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