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

Annotations declare the safety profile (readOnly=false, destructive=false, idempotent=false, openWorld=false), so the bar is lower, and the description adds genuinely useful context beyond them: the operation is asynchronous and the user is notified on completion. It still doesn't say whether the tool returns immediately with a job id or how to poll, but the async disclosure is meaningful added value.

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?

Two tight sentences with zero filler, front-loading what the tool does and following with the async/notification caveat. Every clause earns its place.

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?

With no output schema, the description correctly carries the return-behavior burden by disclosing the async notification flow. Combined with 100% schema coverage for inputs and clear annotations, little an agent needs is missing, though the polling/status path is left unspecified.

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 all three parameters, making 3 the baseline. The description reinforces that videoUrl must be a public URL and that topic drives the AI caption, but adds no syntax or format detail beyond what the schema provides.

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+resource ('Create posts from a video') and adds the two behavioral facts an agent needs: the video becomes the post media and AI writes captions from the topic. It does not, however, differentiate itself from close siblings like create_post_from_image or process_video, which an agent must otherwise disambiguate by name alone.

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?

Usage is implied rather than stated: the '(public URL)' qualifier tells the agent the video must already be hosted, but there is no explicit when-to-use or when-not versus siblings such as create_post_from_image, create_from_link, or process_video. Adequate but leaves routing to inference.

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