Extract data

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. It only states the basic action and does not mention whether the operation is read-only, what happens if the selector matches no element, or whether it returns the first match or an array. For a simple extraction tool, the lack of detail about return behavior and edge cases leaves the agent with uncertainty.

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 a single, front-loaded sentence with no filler. It states the core purpose immediately and omits any irrelevant details. This is appropriately sized for a tool with one parameter and no annotations.

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?

Given the tool's simplicity (one parameter, no output schema, no annotations), the description is partially complete. It conveys the fundamental function but omits details about the exact return value (e.g., innerText vs textContent), behavior on missing elements, and confirms it is a read-only operation. These gaps are noticeable because there is no output schema to clarify the result shape.

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 coverage is 100% and the only parameter (selector) already has a clear description in the schema ('CSS selector of the element'). The tool description adds no additional meaning or usage nuance beyond that, so the baseline of 3 applies. No extra examples, format constraints, or guidance are provided.

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 (extracts) and the target (text of an element on the page). It implies a focused, element-specific extraction that distinguishes it from getPageContent, though it doesn't explicitly name the sibling. The verb and resource are specific enough for basic selection.

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 implicitly tells an agent to use this tool when they need the text of a specific page element, as opposed to the full page content. However, it provides no explicit when-to-use or when-not-to-use guidance, nor does it mention any alternatives or prerequisites. The usage context is inferred rather than stated.

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