Preview Check

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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so the safety profile is covered. The description adds real behavioral value beyond that: the concrete acceptance thresholds (886x1920, <=30 fps, H.264, 15-30 s, <=500 MB, stereo AAC or silent) that define pass/fail.

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 front-loaded blocks (what it checks, when to use it with thresholds, what it returns) with no filler. Every clause carries information an agent needs.

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 an output schema present, the description does not need to detail return values, yet it still summarizes {ok, problems, plan}. Combined with rich annotations and full schema coverage, an agent has everything required to invoke it correctly; only failure-handling guidance is absent.

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?

There is a single parameter (app_dir) with 100% schema description coverage, and the schema already explains it fully as the path containing app.spec.json. The description adds no parameter-level detail, which is the expected baseline when the schema does the work.

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 ('Check') and a precisely scoped resource ('offline readiness of the App Preview set'), then enumerates exactly what is validated: brief, recordings, one preview per locale, ffprobe specs, self-review status. This clearly distinguishes it from siblings such as preview_upload, preview_brief, and preview_review_log.

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 when: before preview_upload' gives an explicit ordering gate that an agent can act on. It does not state when this tool should be skipped or what to do on failure, but the sequencing guidance is unambiguous.

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