Capture Android screenshot

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

Annotations declare destructiveHint=true and readOnlyHint=false, but the description never explains what could be destroyed — a screenshot appears read-only, yet savePath implies writing/overwriting a file on disk, which is left unstated. The mechanism detail (adb exec-out, MCP image return) adds some value beyond annotations, but the destructive side effect is unexplained.

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 tight sentence, front-loaded with the action and return type, with no wasted words. It is structurally clean, though the brevity contributes to the missing parameter and usage guidance.

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 five undocumented parameters, a destructiveHint=true annotation that is never elaborated, and no output schema, the description leaves an agent without enough to call it correctly or safely. Only the surface purpose is covered.

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?

Five parameters with 0% schema description coverage, and the description covers none of them. An agent gets no help on how to target a device (serial/deviceId/deviceName), what maxBytes bounds, or that savePath writes the image to disk.

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 and resource ('capture the current Android screen') and even names the mechanism ('adb exec-out'), plus the return medium ('MCP image'). It does not distinguish itself from close siblings such as screenshot_capture or android_app_snapshot, so an agent cannot tell from the text alone which screenshot tool to pick.

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 statement of when to use this tool versus the many other capture/observation siblings (screenshot_capture, android_app_snapshot, adb_ui_dump, visual_compare). No prerequisites, no exclusions, no routing guidance at all.

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