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

Annotations already declare readOnlyHint=true and openWorldHint=false, and the description is consistent with that, adding the explicit caveat that it 'opens nothing by itself.' It also discloses the backing API version and the absence of an official MCP server, which is genuinely useful context. It does not describe failure modes or limits, keeping it below 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 core message is front-loaded and clear, but the trailing sentence about the official REST API v3.3 and a dated 'checked 22 Oct 2026' note is largely incidental and pads the definition. It could be trimmed without losing actionable information.

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 guidance tool, the description explains what it returns (screens, buttons, fields, step by step) and how to act on it. Nothing essential to calling it correctly is absent, though the API trivia is filler rather than completeness.

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?

Zero parameters, so there is nothing to disambiguate and the baseline is 4. The description does not need to compensate for any schema gap.

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 the resource (campaign report in Campaign Monitor) and, crucially, that this tool only returns step-by-step instructions rather than performing the action. That clarifies an otherwise misleading name ('get_campaign_report' sounds like a data fetch). It does not contrast itself with siblings like campaign_monitor_list_who_did_not_open, so it falls short of 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?

It explicitly explains the two-step workflow: call this to get instructions, then carry them out with the cotlet_browser_* tools in the user's Cloud Browser. What is missing is guidance on when to pick this over sibling report-ish tools, but the sequencing instruction is clear and actionable.

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