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

Annotations already establish readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds real behavioral context beyond that: it blocks up to wait_seconds, returns download links only when finished, and those links expire after an hour and must be downloaded into the project. That expiry/download obligation is genuinely useful and not derivable from the structured fields.

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?

Three short sentences, front-loaded with the core purpose, then the wait behavior, then the return/expiry caveat. Every sentence carries distinct information with no filler.

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?

There is no output schema, so the description must cover return values — it does, describing download links for the main formats plus their one-hour expiry and the need to download them locally. It omits what is returned when the animation is still unfinished (partial progress fields), a minor gap for a polling tool.

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%, with both job_id and wait_seconds fully documented in the schema (including the default of 45). The description restates wait_seconds implicitly ('waits up to wait_seconds') but adds no format or semantics beyond what the schema already provides, so the baseline of 3 applies.

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 resource (animation progress) and ties it explicitly to the originating sibling, animate_mascot, so it is clearly the polling counterpart to that tool. An agent can distinguish it from animate_mascot, suggest_animations, and get_download 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?

The description establishes the usage context: call this after animate_mascot to check the animation started there. It does not name a competing alternative or explicitly state when not to use it, but the sequencing with animate_mascot is unambiguous.

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