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

Annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, so the safety profile is covered. The description adds no behavioral context beyond what the annotations provide — it doesn't explain why a swipe is flagged destructive or how the swipe interacts with device state.

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 sentences, front-loaded with the core action, zero padding. Slightly weakened by the vague "etc." tail but otherwise efficient.

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?

Adequate for selection given full schema coverage and annotations, but it omits how to choose between android_swipe and android_tap, and gives no coordinate-system or duration context beyond the schema. Complete enough to invoke, not enough to route confidently.

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 100%, so the schema fully documents all 7 parameters including duration_ms default and the channel_account_id requirement. The description adds no syntax, coordinate-system, or format detail beyond the schema, so the baseline 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 verb (swipe/drag) and resource (Android device screen) with the coordinate-to-coordinate scope. The verb naturally distinguishes it from siblings like android_tap or android_key, though no sibling is named explicitly.

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 for scrolling, opening app drawer, etc." gives implied usage scenarios but no explicit when-to-use-vs-alternatives guidance (e.g., when to swipe instead of android_tap). The trailing "etc." leaves the boundary fuzzy.

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