click_nth_element

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

With no annotations, the description carries the full burden of behavioral disclosure. It only states the action and indexing convention, but omits important behaviors such as what happens if the element is not found, whether it waits for the element to exist, or whether it requires the element to be visible. For a mutation tool, this is a significant gap.

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?

A single, front-loaded sentence with no wasted words. It efficiently communicates the core action and the critical indexing detail.

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 simple two-parameter tool with an output schema present, the description is mostly adequate but misses edge-case context such as error behavior, waiting, and visibility requirements. Given the existence of related tools like click_visible_elements and wait_for_element_visible, an agent could benefit from additional context about when this action will succeed.

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 0%, so the description must compensate. It does explain the 'number' parameter as the 1-indexed position and 'selector' as the matching query, but it does not clarify the selector syntax (e.g., CSS selector) or whether number refers to the order in the DOM or in the visible set. Partial compensation, but not complete.

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 clearly states the action (click) and the resource (the Nth element matching a selector), and it specifies 1-indexing, which adds precision. However, it does not explicitly differentiate this tool from siblings like click_visible_elements or click, so it misses the highest bar.

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 implies the usage case: click a specific element by its index among matches of a selector. There is no explicit guidance about when to use this tool instead of click, click_if_visible, or click_visible_elements, nor any mention of exclusions or prerequisites.

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