session_click

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

Beyond the destructiveHint/openWorldHint annotations, the description discloses side effects: scrolls into view, dispatches a real press/release at centre, returns {clicked}, and fails loudly with 'Element not found' instead of silently mis-clicking. This is behaviorally transparent.

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?

Four short, information-dense sentences with no filler; the core action and target are front-loaded, and the distinctive behaviors follow. Every sentence 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?

Despite no output schema, the description reports return shape, error behavior, selection alternatives, and event semantics, giving an agent everything needed to call it correctly. tabId is left to the schema, which documents it, so no important gap remains.

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?

The schema already covers all parameters (100%), and the description adds the selector-vs-ref relationship and that refs come from session_snapshot. However, it says 'or by an @eN ref' while the schema marks selector as required, so the relationship is not fully consistent; an agent could pass only ref and fail validation.

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 the specific action ('Click'), the target element, and the two ways to identify it (CSS selector or @eN ref), so an agent immediately understands the operation. It also differentiates from sibling tools by emphasizing a real mouse press/release rather than synthetic event dispatch.

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?

Gives clear context for when to use the tool: when an element needs to be clicked with real input events ('handlers that ignore synthetic events still fire') and when a ref from session_snapshot is available. It does not name alternative sibling tools or state exclusions, but the behavior description makes selection straightforward.

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