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

The annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, and openWorldHint=false, and the description is consistent with all of them by stating it 'opens nothing by itself.' It adds real context beyond the annotations: the return payload is step-by-step UI guidance (screens, buttons, fields) and the action must be finished through the separate browser tools.

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 core behavior is front-loaded, which is good, but the sentence is padded with meta-framing ('from ChatGPT, Claude or any AI agent') and a dated API fact ('checked 11 Oct 2026') that does not help an agent decide or call the tool. The useful content could be stated in half the words.

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?

It explains what is returned (step-by-step screens/buttons/fields) and how to follow through with the browser tools, which is appropriate given there is no output schema. However, with zero parameters it never explains how the target eSIM or plan is identified, nor what state the account must be in, leaving a real operational gap.

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 tool takes zero parameters and the schema is fully described, so there is no parameter semantics for the description to compensate for. Baseline for a parameterless tool applies, and nothing in the description misrepresents the inputs.

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 names a specific verb and resource ('Top up eSIM in the user's own Airalo account') and then immediately clarifies the actual behavior: it returns step-by-step instructions rather than performing the action. That clarification rescues what would otherwise be a misleading name, though the framing still leans on 'top up' as if the tool acted on the account.

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?

It does give a workflow: this tool returns the steps, and then the agent should use 'cotlet_browser_*' tools in the Airalo Cloud Browser to actually do it. But it never says when to prefer this over siblings like airalo_buy_esim or cotlet_app_guide, nor states prerequisites such as being logged in or owning an active eSIM.

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