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

Annotations already declare destructive, non-idempotent, open-world behavior, so the bar is lower; the description still adds real value by explaining the post-click return payload (elements and text in view, same numbering), the no-change signal, and the refusal policy for payment and auth surfaces. It does not cover what happens when an element is missing or off-screen, or how dialogs are surfaced.

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?

Front-loaded with the core action and target, then modifiers, then return behavior, then safety refusals — a sensible priority order with no filler. The telegraphic style ('Answers the page after it') is compact but slightly oblique.

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 seven optional parameters, no output schema and destructive annotations, the description does the heavy lifting on return shape and edge cases (new tabs, unchanged page, refused clicks). Minor gaps remain around element resolution failures and dialog interception, which the schema covers only partially.

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%, so every parameter including the undocumented-in-description `dialog` and `dialog_text` is already explained. The description adds only a light framing of element-vs-coordinate mutual exclusivity and the double/right-click shortcuts, which largely restate the schema.

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?

States a specific verb (clicks) plus the exact targets (element number or x/y point) and the modifier variants (double, button: right). It is unmistakably distinct from siblings like cotlet_browser_hover, cotlet_browser_drag, cotlet_browser_press and cotlet_browser_select.

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 clear usage context plus an explicit when-not: pay/buy buttons and sign-in/account pages are refused, and new-tab links are redirected into the current tab. It does not name alternative tools (e.g. hover vs click), so it stops short of full routing guidance.

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