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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds genuinely new behavioral context: it is free and opens no browser session, which tells the agent this call has no cost or session side effect. It stops short of saying whether the guidance is cached or how current it is, so a 4 rather than 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?

It is front-loaded with the purpose and the trigger sentence appears early, with the scoping caveat last. The middle enumeration of return contents is a long run-on list that could be tightened, but every element listed is informative rather than filler.

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 carries the burden of describing returns, and it does so by enumerating the guide's contents (browser choice, sign-in link, method, screens, notes, dedicated tools). Combined with annotations covering the safety profile and a fully documented two-param schema, an agent has enough to call it correctly; only the freshness/format of the returned guide is unaddressed.

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 both parameters (app, task) are already documented with their own descriptions and the default (Bayut) is stated in the schema. The description mentions working 'in an app' but adds no format, slug, or task-phrasing guidance beyond what the schema provides, so the baseline 3 applies.

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 uses a specific verb+resource framing ('How to work in an app') and enumerates exactly what the guide returns: which browser to use for the workspace, the sign-in link, the step-by-step method, screens/menus/actions, notes, and dedicated tools. This clearly separates it from the sibling cotlet_browser_* action tools and from cotlet_apps, so an agent can pick it without opening the 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 an explicit trigger ('Call it before the first browser step in an app') and an explicit coverage rule ('Works for any web app; one outside Cotlet's catalog gets the general method'). It also points to the app's dedicated tools when they exist, so the agent knows what to do after reading the guide.

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