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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuine context beyond that: the URL is 'short-lived' (expiry), 'fresh' (each call mints a new URL), and only valid for 'completed owned' generations, which tells the agent about precondition failures.

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?

One tight sentence with no filler. It leads with usage context rather than the action, which is a minor front-loading weakness, but nothing 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?

An output schema exists, so return values need no explanation, and the mutation/expiry behavior is covered. What is missing is any guidance on choosing outputRole and what jobId must reference, which is a real gap given 0% schema description coverage.

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 0%, so the description must carry the burden, yet it explains neither jobId nor outputRole. The enum values 'primary' and 'last_frame' are entirely uninterpreted — a caller has no idea what a last-frame attachment means or what the default is. Only the vague notion of 'one completed owned generation' maps to jobId.

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 ('create') and resource ('fresh short-lived attachment URL') scoped to 'one completed owned generation', which is concrete enough to distinguish it from siblings like get_generation_status or list_media. It stops short of naming any sibling it is not, so it is clear but not maximally differentiated.

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?

'Use this from the MaxVideoAI result app' gives a situational cue, and 'completed owned generation' implies a precondition. However, no alternative is named and no exclusion is stated — an agent cannot tell from this whether a plain status or media-list call would already return a usable URL.

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