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

Annotations already establish readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. Beyond that the description discloses meaningful behavior the annotations cannot: the 30-day usage window, the Pro/Free tier thresholds, and the two branches of the returned upgrade/manage link.

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?

Two sentences, front-loaded with what is shown, followed by the return value, then the scope exclusion last. Every clause carries information; there is no filler or restatement of the title.

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?

There is no output schema, so the description carries the burden of describing returns, and it does: it names the compared counts, the tier limits, and the type of link returned. An agent has everything needed to call this and interpret the result.

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 per the rubric the baseline is 4. There are no parameters for the description to clarify, and it correctly does not invent any.

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?

States a specific verb (Shows) and resource (the user's Camberstack plan) and even specifies the payload: Google Ads accounts used in the last 30 days against the plan quota. It also explicitly disambiguates from Google Ads account-level billing, which no sibling covers, so the agent can separate it from the rest of the tool set.

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?

Provides a clear scoping exclusion ('Camberstack subscription only, not a Google Ads account's own billing, invoices or ad spend'), which functions as a when-not rule. It does not name an alternative tool, but for a zero-parameter account-scoped lookup there is little genuine selection ambiguity among siblings.

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