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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, and the description reinforces this by stating the tool 'opens nothing by itself' and only returns screens/buttons/fields guidance. It also explains why browser automation is required (no public AestheticsPro API, Enterprise-only custom work), which is context annotations cannot provide. It does not describe the shape or length of the returned steps in detail, so it is not a full 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 structure is front-loaded and logical: purpose, then behavioral disclaimer, then the workaround path. However, the closing paragraph about AestheticsPro's $350/month Enterprise plan pricing and a future-dated check ('checked 11 Nov 2026') is verbose vendor trivia that an agent invoking the tool does not need; the core point (no public API) could be stated in one clause.

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 return-value burden and does so by stating the tool returns step-by-step instructions covering screens, buttons and fields. It also explains what to do after receiving them and why the browser route is necessary. Nothing an agent needs in order to call this zero-parameter tool correctly is missing.

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 additionalProperties is false, so there is no parameter meaning to add beyond the schema. A baseline 4 is appropriate; nothing in the description conflicts with or expands on the empty schema.

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 verb and resource: 'Create email list in the user's own AestheticsPro account', and immediately qualifies the mode of action ('Returns how to do it... and opens nothing by itself'). That distinguishes it from the sibling creation tools like create_text_list or create_email_template by naming a distinct resource. It stops short of explicitly contrasting itself with those siblings, so a 4 rather than a 5.

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?

The usage chain is explicit: call this tool to get step-by-step instructions, then perform the action with the cotlet_browser_* tools in the user's AestheticsPro Cloud Browser. That is clear when-to-use and next-step guidance. It offers no explicit when-not-to-use or named alternative sibling, which keeps it at 4.

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