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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real behavioral context beyond that: it opens nothing by itself, produces human-readable steps, and must be followed by browser tool calls. It does not describe the exact return format or any auth prerequisites, so it stops short of a 5.

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 operational core (what it returns, that it opens nothing, and which tools to use next) is front-loaded in the first sentence. The closing note about Airalo's API being partner-only is somewhat awkwardly worded and repetitive ('Airalo's official API: Airalo has an API only for...'), but it justifies why browser automation is required, so it mostly earns its place.

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 input parameters and no output schema, the description carries the burden of explaining what comes back, and it does so by naming the content (screens, buttons, fields) plus the required follow-up tool family. It stops short of describing the exact response shape or whether the steps are tailored per platform, which is a minor gap for a guidance-only tool.

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 empty with additionalProperties=false, so there is nothing for the description to disambiguate. Baseline for a zero-parameter tool is 4; the description correctly adds no param noise.

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 (check data usage in the user's own Airalo account) and then makes the key distinction that the tool returns step-by-step instructions rather than performing the check. It explicitly separates itself from the cotlet_browser_* tools that actually carry out the steps, so an agent can pick it correctly without opening a schema.

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 gives a clear usage path: call this first to get the screens/buttons/fields, then act with cotlet_browser_* tools in the user's Airalo Cloud Browser. It also scopes applicability to the user's own account and notes the official API is only for reseller partners, implying this path is for consumer accounts. There is no explicit 'do not use when' clause, which keeps it below a 5.

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