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

Annotations already declare the full risk profile (readOnlyHint=false, destructiveHint=true, openWorldHint=true, non-idempotent), so the description needn't restate safety. What it does add is genuinely useful: 'Answers the page after it: the elements and text in view, with the same numbers' discloses the return shape and that element numbering is stable across steps, which matters because there is no output schema. It does not say whether selection waits for navigation or submits a form, which is the main residual risk for a destructive browser step.

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?

Three short sentences, front-loaded with the core action, then the exception case, then the return behavior. No filler, and the numbered-element contract is stated once without repetition.

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, the description usefully covers the return value, and the dialog parameters are fully documented in the schema. The remaining gap is timing/side effects – whether the step waits for load and whether a selection can submit or navigate – but for a single-element browser action this is close to complete.

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%, so baseline would be 3, but the description earns above baseline by disambiguating `option`, whose schema text is merely 'The option.' – it clarifies that either the visible label or the underlying value is accepted. It also reinforces that `element` is the number from the previous step's answer, tying parameters to the read/select numbering loop.

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?

Names a specific verb (chooses) and a specific resource (an option in drop-down `element`), and the parenthetical 'its label as listed, or its value' pins down what an option is. It is clearly distinguishable from cotlet_browser_click only indirectly, via the 'home-made drop-down' caveat rather than an explicit contrast.

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 a real branch condition: use this for a native drop-down, but for a home-made drop-down 'click it, then click the option' – effectively routing the agent to cotlet_browser_click. It stops short of naming that sibling or stating what happens when the element is not a list at all.

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