browser_select_option

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

Annotations already signal mutation with readOnlyHint=false and destructiveHint=true. The description adds useful behavioral context by stating this tool performs a 'real interaction' that the page observes, unlike browser_evaluate. It does not contradict the annotations and clarifies the interaction model.

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 with no filler: the first states the action and key parameter semantics, the second gives a compact, useful rationale for preferring this tool over alternatives. Every clause earns its place.

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 sufficient for the core task: it specifies what to select, how to identify the option, and why this tool should be used over siblings. It does not describe selector formatting or error behavior, but the output schema exists and sibling conventions likely supply the rest.

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 coverage is low (33%), so the description must compensate. It meaningfully clarifies the `value` parameter by saying it can be either a visible label or an option value, but it leaves the `selector` parameter format (e.g., CSS selector) unstated. This is partial compensation for the undocumented parameters.

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 ('Choose') and resource ('an option in a dropdown (`<select>`)') and explicitly states the two identification modes: visible label or value. It also distinguishes itself from clicking with arrow keys and from browser_evaluate, making its purpose unambiguous.

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?

The description explicitly says 'Use this rather than clicking the dropdown and pressing arrow keys' and explains why browser_evaluate is unsuitable ('changes it without the page seeing a real interaction'). This gives clear when-to-use and when-not-to-use guidance relative to named alternatives.

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