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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds genuinely new behavioral facts: it is free, requires no browser session, and degrades gracefully to a general method for apps outside the catalog. It stops short of describing the shape of the returned guidance, but the added context is substantive.

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 purpose and the call-before-first-step instruction are front-loaded, and the enumerated coverage list is useful for routing. It is a single dense run-on sentence, so the Arborgold action list and the fallback clause are harder to scan than they need to be, but no clause is 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 explaining what comes back, and it does: browser choice, sign-in link, method, screens, menus, actions, notes, and dedicated tools. Combined with the explicit pre-step trigger and the uncatalogued-app fallback, an agent has everything needed to call it 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?

Schema coverage is 100% and both parameters are documented in the schema, including the Arborgold default for 'app'. The description reinforces that the app may be a name or Cotlet slug and that the task is the user's own wording, but adds little beyond the schema. Baseline 3 applies when the schema does the heavy lifting.

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 states a specific resource and outcome: guidance on how to work in an app via the Cloud Browser, covering browser choice, sign-in link, step-by-step method, screens/menus/actions, notes, and dedicated tools. It is clearly distinguishable from the cotlet_browser_* action tools and the arborgold_* action tools, which perform steps rather than explain 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?

It gives an explicit trigger: 'Call it before the first browser step in an app,' and clarifies scope with 'Works for any web app; one outside Cotlet's catalog gets the general method.' It does not name a specific alternative tool to use instead when already mid-task, but the sequencing guidance is strong enough to route the agent correctly.

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