is_displayed

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

No annotations are provided, so the description carries the full burden of behavioral disclosure, yet it only restates the purpose. The timeout parameter (default 10) implies the tool may poll for visibility, but the description does not say whether it returns immediately, waits until timeout, returns false, or throws when the element is not visible — nor does it state the return type. Selenium's isDisplayed() semantics differ meaningfully from a wait-based visibility check, and the description resolves none of this ambiguity.

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 eight-word sentence with no filler and the core purpose front-loaded — it earns its place. The brevity is partially achieved by omitting the behavioral detail scored lower above, so it is efficient rather than exemplary.

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?

With no output schema and no annotations, the description must disclose the return value and wait/failure semantics, but it covers neither. The presence of a timeout parameter makes the polling-vs-immediate distinction especially relevant, and an agent cannot tell whether a non-visible element yields false or an exception. For a state-checking tool in a very large sibling group, this definition is incomplete.

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 100%: by ('Locator strategy'), timeout ('Wait timeout in seconds'), and selector all carry descriptions in the schema. With the schema doing the heavy lifting, the baseline of 3 applies even though the tool description itself adds no parameter-level detail.

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 specific verb ('check') and resource ('element ... visible on the page'), making the core function clear and non-tautological. It reads as a query for visibility state rather than an interaction or mutation. However, it does not explicitly differentiate is_displayed from the sibling assert_element_visible, which targets the same visibility concept.

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 provides no when-to-use context, no exclusions, and no mention of alternatives. Among a large sibling set containing is_enabled, wait_for_element, assert_element_visible, and assert_element_not_visible, the agent gets no routing signal about when an immediate visibility check is the right choice versus waiting or asserting.

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