Click an element (human-like)

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

The description adds meaningful behavioral context beyond the annotations: it explains the human-like pacing, that only the first visible match is clicked, and exactly what will be reported after the click. It also adds a caution about not using it for rating or messaging. The 'Read-only actions only' phrasing is a usage constraint rather than a direct contradiction of readOnlyHint=false, since clicking can still navigate or alter page state.

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 deliver the core behavior, the output report, the intended use case, and an exclusion guard. Every phrase earns its place, and the most important behavioral details are front-loaded.

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 2-parameter tool with no output schema, the description provides enough to call it correctly: the required selector, optional waitMs, and the expected results. It could be even more complete by describing what happens if no element matches or if the selector is invalid, but those are not critical gaps.

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 selector parameter lacks its own schema description, but the tool description partially compensates by explaining that selector selects the first visible matching element and that the match count is reported. waitMs is well described in the schema. The description does not clarify selector syntax (CSS, XPath, etc.), so compensation is only partial.

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 names a specific action ('click'), a specific resource ('first visible element matching a selector on the current tab'), and adds concrete behavioral details (paced mouse movement, reported URL/title/checkpoint state/match count). This clearly distinguishes it from siblings like debug_navigate or debug_find.

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 when to use it ('For exploring pagination / menus while adapting selectors') and gives a 'never use' exclusion for applicant-changing actions. It does not name alternative sibling tools explicitly, so it is slightly below a perfect when/when-not/alternatives statement.

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