apps_export_begin

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so safety is largely covered. The description usefully adds that no save or editing control is needed, but it omits the non-obvious consequence of idempotentHint=false — that each call may produce a distinct snapshot — which an agent retrying would want to know.

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 no filler, and the purpose is front-loaded before the non-requirements. Minor demerit for the vague 'Fix' phrasing, which spends words without adding clarity.

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?

For a tool with two required, entirely undocumented parameters and no output schema, the description should carry the load of explaining the digest requirement and the snapshot lifecycle. It instead covers only what the annotations already imply, leaving the agent under-informed at call time.

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% and the description says nothing about either parameter. 'expectedPackageDigest' is especially opaque: an agent has no hint what digest format to supply or where it comes from, and appId is only inferable from the tool name. The description fails to compensate for the schema gap.

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?

The description names the resource (a snapshot of an already saved App) and the intent (feeding file_download), which is more than the bare name offers. However, the verb 'Fix a read-only snapshot' is ambiguous wording that an agent could read as repairing rather than creating, and it never states plainly that it begins an export operation.

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 clause 'Does not Save or require editing control' implies when to prefer this over apps_save, and the mention of file_download implies the downstream workflow. But it never explicitly says 'use this when exporting a saved app' nor names apps_save as the alternative, so the guidance is only implied.

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