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

Annotations only say readOnly=false, openWorld=true, idempotent=false, destructive=false. The description adds the material behavior an agent actually needs: generation consumes credits at the format's price, confirmation is required first, execution is asynchronous with rough latency by content type, results land in the media library, and credits are refunded on failure. That is substantial value beyond the annotations.

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?

Core purpose is front-loaded in the first sentence and every subsequent sentence carries operational information (price, confirmation, async, polling, refunds, recipes). It is dense but slightly overlong, with the recipe rule appearing twice (once in the body, once in the final sentence).

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 14-parameter, credit-spending, async generator, the description covers cost, confirmation, execution model, follow-up tool, output destination, failure handling, and the recipe shortcut. An output schema exists, so return-value shape needs no further explanation.

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%, so the baseline is 3; the description earns more by explaining the formatId/recipeId mutual requirement (neither is schema-required) and by defining recipe precedence over passed values. It does not add detail on hook, angle, or mediaIds beyond what the schema already documents.

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 (generate) and resource (content in a Studio format) and immediately points to studio_formats for the format catalog, making it clearly distinct from studio_status (polling) and studio_recipes (saved presets). An agent can pick it over the siblings 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 explicit routing rules: check studio_formats for price/inputs, pass formatId or recipeId, tell the user the price and get confirmation first, then poll with studio_status using the returned generationId. It also covers the recipe path and the precedence rule ('what you pass yourself wins'), leaving little to inference.

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