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

The description adds real context beyond annotations: it opens nothing itself and only returns screens/buttons/fields for the user to follow, which is consistent with readOnlyHint=true and destructiveHint=false. However, it stops short of describing the shape of the returned guidance (format, length, whether it varies by task), which matters for a no-parameter tool whose entire output is a procedure.

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 core is front-loaded and the 'opens nothing by itself' constraint lands early, but the trailing sentence about ClickSend's official REST API and narrow MCP server is tangential to invoking this tool and adds noise without decision value.

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 input or output schema and an annotation set covering safety, the description supplies the missing workflow pieces: what it returns and which tools complete the action. Only the precise form of the returned guidance is left implicit.

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 to document; the description appropriately spends no space on parameter semantics.

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 names a specific verb and resource (adding to the opt-out list) and then clarifies the crucial nuance that the tool only returns instructions rather than performing the action. It is distinguishable from the sibling clicksend_remove_opted_out_contacts and the cotlet_browser_* tools, though the name/description tension briefly suggests a write before being corrected.

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 explicitly routes the agent: get the step-by-step here first, then execute with the cotlet_browser_* tools in the ClickSend Cloud Browser. It does not state when NOT to use it or name a specific app-guide alternative, but the workflow context is clear.

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