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

Beyond the destructive/openWorld/non-idempotent annotations, it discloses that the tool acts as the user on the site, that certain action classes (payment, account/sign-in) are blocked, what is returned after the click, and the billing model with a 3-minute idle expiry. These are exactly the operational constraints an agent cannot infer from structured fields.

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?

Four sentences, all load-bearing: action, side-effect return, refusal policy, and cost/lifetime. The final sentence packs two distinct facts (credit cost and 3-minute idle expiry) into one long clause, which slightly hurts scanability.

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 covers the return value (URL and title), the side-effect profile, refusal conditions, and the session/cost lifecycle. An agent has everything needed to decide and invoke correctly.

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?

The single parameter is fully documented in the schema (100% coverage), and the description's 'by its number in the page's element list' merely restates the schema text. No extra guidance on how to obtain valid element numbers, so baseline 3 is appropriate.

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) and resource (a link, button or other element of the current page in the user's browser) plus the addressing mechanism (its number in the element list) and the return (URL and title). This clearly separates it from siblings like cotlet_browser_press, cotlet_browser_type, cotlet_browser_select and cotlet_browser_navigate without needing to name them.

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 explicit exclusion rules: pay/buy buttons and buttons on account or sign-in pages are refused, which tells the agent when this call will fail. It also frames the cost/session lifecycle (credits per started minute, session ends 3 minutes after the last call), but it never explicitly routes the agent among alternatives such as press vs select vs type for a given widget.

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