get_screenshot

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

With no annotations, the description carries the full behavioral burden yet only restates 'resizing and format options,' which the schema already contains. It does not disclose prerequisites (e.g., simulator booted), whether capture is safe/non-destructive, or any timing/rate behavior.

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 no filler. It is efficiently sized, though the terseness comes at the cost of the guidance and behavioral detail noted elsewhere.

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?

The output schema plus 100% parameter coverage mean params and return values need no explanation here. However, for a capture tool with no annotations, the description omits the prerequisite state (booted simulator) and any note on what is produced, leaving it only minimally complete.

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 every parameter (scale, format, quality, device_id) is already documented in the schema. The description adds only a vague gesture at 'resizing and format,' yielding the baseline 3 with no extra semantic value.

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 (capture) and resource (screenshot from the simulator) along with the capability area (resizing, format). It is clearly distinguishable from video-oriented siblings like start_recording/stop_recording, though the description never names a sibling to sharpen the boundary.

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: nothing says the device must already be booted, nor when to prefer this over start_recording for video capture. Usage context is left entirely to inference.

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