emulate_device

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

With no annotations, the description carries the full behavioral burden. It does disclose the core effects: viewport sizing, pixel ratio, and touch emulation via CDP. However, it does not explain whether emulation persists across navigations, how to reset it, or any side effects on subsequent commands.

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 short sentences carry all the essential conceptual information with no filler. The main action is front-loaded and the effects are listed immediately afterward.

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 description is adequate for a simple, all-optional-parameter emulation tool, but it lacks lifecycle and reset information. Given that no annotations or output schema are present, the description should have covered persistence behavior or how to return to a normal desktop viewport.

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 80%, so the schema already documents most parameters. The description adds a useful conceptual mapping to viewport, pixel ratio, and touch, but it does not clarify relationships such as custom width/height overriding device presets or the meaning of the mobile flag.

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-resource pairing: 'Emulate a mobile device using Chrome DevTools Protocol.' It also lists what is adjusted (viewport, pixel ratio, and touch), which makes the tool's function concrete and distinguishes it from the browser-navigation and inspection siblings.

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 guidance about when to use this tool versus alternatives, when it should be called in a browser session, or whether it should be used before navigation. No exclusions or alternative tool references are given.

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