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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, and the description is consistent with them ('opens nothing by itself'). Beyond that it discloses the useful behavioral facts: the tool returns step-by-step screens/buttons/fields and requires the cotlet_browser_* tools to actually act, which annotations cannot convey.

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 short, but the front-loaded sentence is the misleading one, so the structure works against understanding. The trailing note about official APIs and 'checked 31 Oct 2026' is incidental trivia that does not help an agent decide or call.

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?

For a zero-parameter, no-output-schema guide tool it covers what it returns (step-by-step screens, buttons, fields) and what to do next (cotlet_browser_* in the user's Avantio Cloud Browser). The only gap is its silence on prerequisites such as whether the Avantio Cloud Browser session must already be open.

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, so there is nothing for the description to disambiguate; baseline 4 applies. It correctly implies no input is needed before returning instructions.

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 first sentence says 'Send guest message', which is what the tool does NOT do; the real purpose (returning step-by-step instructions for the user to send a guest message in Avantio) only emerges in the second sentence. The contradiction between the leading claim and the actual behavior makes the purpose clear only after reading the whole text.

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 route the agent onward: after getting the steps, use the cotlet_browser_* tools in the Avantio Cloud Browser, which the sibling list confirms exist. However, it gives no when-not guidance, no alternatives for other Avantio operations, and the mention of official APIs exists only as trivia rather than as a routing signal.

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