browser_select_optionSelect option values in a browser page's dropdown or multi-select element, supporting single or multiple choices to control forms during automation.
Select options in a select element.
| Name | Required | Description | Default |
|---|---|---|---|
| values | Yes | Option values to select; pass multiple for multi-select. | |
| timeout | No | ||
| selector | Yes | ||
| sessionId | Yes |
Changes observed during successful MCP inspections.
v0.1.14Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must carry the behavioral burden. It only says 'Select options in a select element' and does not explain side effects, whether selection triggers change events, whether the element must be visible or interactive, or what happens if a value is not available. This leaves the agent without crucial behavioral information for a browser mutation operation.
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?
The description is short and front-loaded with the core action; every word earns its place. However, it is arguably under-specified for the tool's complexity, so it earns a high conciseness score but not the top score, which expected richer useful content without redundancy.
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 browser automation tool with four parameters, no annotations, low schema coverage, and no output schema, the description is far too thin. It leaves important gaps around usage, parameter meaning, side effects, and success/failure behavior. An agent would need guesswork or external domain knowledge to invoke the tool correctly.
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 only 25%, and the description adds essentially no parameter semantics. It does not mention sessionId, selector, values, or timeout, nor how selector is interpreted (CSS/XPath/text), what timeout unit is used, or how multiple values map to multi-select. The schema itself provides a description only for values, and the description does not compensate for the remaining undefined 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 states a clear verb ('Select'), a specific resource ('options in a select element'), and is immediately distinguishable from siblings like browser_click and browser_fill. It is plain and correct, though it does not explicitly contrast itself with those sibling tools.
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 gives no guidance on when to use this tool versus alternatives such as browser_fill, browser_fill_form, or browser_click. There is no mention of prerequisites, the need to wait for the select element, or a note that browser_fill_form might be more appropriate for filling whole forms. This is a general statement of purpose rather than usable selection guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.