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

Goes well beyond the annotations by disclosing credit costs per output type (video 25/platinum 50, card 10, set 10 per slide), that charges happen once, the ~1 minute blocking wait for cards/sets, the asset_urls return with slide 1 first, and the async run-id + polling path for videos. This is exactly the behavioral context an agent needs before committing credits.

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?

Purpose is front-loaded and every sentence carries information, but the embedded credit/pricing clause is dense and slightly awkward ('a set 10 a slide'), costing some readability. Still well-sized for the amount of behavior conveyed.

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 credit-spending, async-capable render tool, the description covers cost, blocking vs polling behavior, and the correct follow-up tools. With an output schema present it need not detail return shapes, and nothing needed to invoke it correctly is missing.

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 both parameters (version, thread_id) are already documented in the schema. The description adds no per-parameter syntax or format detail beyond what the schema provides, making the baseline 3 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 states a concrete verb+resource: rendering a Studio design or video out to files. It is clearly distinguishable from most siblings, though it never names or contrasts with the near-neighbor render_asset, so the differentiation is left implicit.

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?

It gives rich downstream usage guidance (poll get_run until terminal, then show the human the file or post_run) but does not say when to choose this over render_asset or studio_card. Usage is implied through the output-mode branches rather than stated as explicit selection criteria.

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