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

Annotations only declare the generic safety profile; the description adds real behavioral context: it is free/no-credit, rate-limited to one batch a day per app, and returns videos that render asynchronously in the grid. It doesn't cover failure modes or what happens to an existing pending batch, keeping it below 5.

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?

Information is front-loaded (what it does, then cost, then trigger, then rate limit) with little waste. The prose is somewhat run-on and packed with clauses, but every sentence carries a distinct fact.

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-format details aren't strictly required, yet the description still notes the videos render over time. Cost, rate limits, trigger timing, and regenerate behavior are all covered for a 2-param tool; only edge cases like batch expiration remain 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 description coverage is 100%, so both parameters are already documented, including the url's optionality when an app is on file. The description only adds flavor about regenerate ('three more with other faces on the same hooks'), which is a marginal gain over the schema.

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 and output: turns an app link into three finished UGC videos with distinct AI influencers, using the app's screenshots and hook lines. This is clearly distinguishable from siblings like make_video, make_videos, and suggest_hooks.

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 triggers ('Call it as soon as the user gives an app link') and the regenerate condition ('from the next day on, regenerate true makes three more'). It does not name sibling alternatives or state when NOT to use it, so it falls short of a 5.

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