change_permission

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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the safety profile is largely covered. However, the description says nothing about the two-phase preview/approval flow (owner_approved gating) that governs whether the call actually mutates the device — the single most important behavioral fact here — leaving it buried in a schema field. The claim of non-destructiveness also sits awkwardly with a revoke operation that can break an app, and the description does not reconcile that.

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?

A single front-loaded sentence with zero filler; the verb pair and the scope constraint both land immediately. Nothing in it is redundant or padded.

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 5-parameter mutation tool with a mandatory approval gate and no output schema, the description is far too thin. An agent reading only the description would not know a call without owner_approved yields a preview instead of an action, nor what happens on failure or how the change can be reversed.

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 only 40%, so the description carries some burden. It usefully clarifies that permission takes a fully-qualified identifier such as android.permission.CAMERA, which the schema does not document, but it says nothing about action semantics, package format, or when device is required beyond what the schema already states.

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 uses a specific verb pair (grant/revoke) and a specific resource (one app permission), with a concrete example of the permission identifier format. It does not differentiate itself from the near-sibling change_packages, which likely handles bulk permission changes, so an agent must infer the single-permission scope distinction.

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?

There is no explicit when-to-use, when-not-to-use, or named alternative. The phrase 'one app permission' implicitly contrasts with the bulk change_packages tool, but the agent is left to infer that routing decision rather than being told it.

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