app_info

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

Annotations already declare readOnlyHint=true, so the safety profile is covered, but the description adds nothing behavioral beyond the field list. It does not say whether the package must be installed, whether live fields like 'running processes' and 'open display' require root or fail on non-running apps, or what a missing package yields — all material for an inspection tool with side queries.

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 compact sentence with the subject front-loaded and no filler. It reads as a noun phrase rather than an action statement, which is a minor structural weakness but costs no tokens to waste.

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 no output schema, the description does the right thing by enumerating return fields, and for a read-only single-parameter tool that is close to sufficient. Gaps remain around failure modes (package not installed, permission/root needs) and the exact meaning of the package argument.

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%: the single required 'package' parameter has only a regex pattern and no textual semantics. The description's phrase 'One package's ...' barely gestures at the parameter and never clarifies that it is the application ID (e.g. com.example.app) rather than a label or path, so it fails to compensate for the coverage 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?

Names a specific resource ('One package') and enumerates the attributes returned — version, SDK levels, debuggable flag, paths, launcher activity, processes, display, permissions. The singular framing implicitly distinguishes it from the sibling list_apps, though the description never states that contrast and lacks an explicit verb like 'Get' or 'Inspect'.

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 when-to-use guidance, no prerequisites, and no mention of alternatives such as app_perf or list_apps. The agent must infer entirely from the field list that this is a static metadata lookup for a single installed package.

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