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

Annotations already declare readOnlyHint, idempotentHint and non-destructive behavior, and the description is consistent with them by stating the tool opens nothing by itself. It adds genuinely useful context beyond the annotations: the output is a step-by-step walkthrough covering screens, buttons and fields, and the follow-up action must be performed through the browser tools.

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?

Three sentences, front-loaded with the action and immediately corrected with the no-side-effect caveat and the follow-up tooling. The only filler is the 'from ChatGPT, Claude or any AI agent' clause; the API-availability sentence is tangential but does help an agent decide whether an official API path exists instead.

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 parameterless, read-only guide tool with no output schema and full annotation coverage, the description supplies the essential missing pieces: it is a guide, not an executor, and the actual browser work goes through cotlet_browser_*. Nothing an agent needs in order to call it correctly appears to be absent.

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 the schema carries no semantic burden and the description is not required to explain inputs. Baseline for a parameterless tool is 4; nothing in the description misrepresents or omits input expectations.

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?

Names a specific verb (List) and resource (replies and leads) scoped to the user's own Mailshake account, and explicitly resolves the ambiguity that it returns step-by-step instructions rather than performing the listing ('opens nothing by itself'). The name alone would suggest a data-returning call, so the clarification is necessary and present, though it arrives after the opening claim rather than front-loading the guide nature.

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 describes the intended workflow clearly: call this first, then execute the steps with cotlet_browser_* tools in the Mailshake Cloud Browser. However, it never states when to choose this tool over an alternative such as cotlet_app_guide or mailshake_list_campaigns, and offers no explicit exclusion or precondition.

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