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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds the meaningful extra that no authentication is required, which annotations do not express, though it omits any caching or data-freshness notes.

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?

A single compact line, front-loaded with the resource and metric, plus a bilingual restatement. The duplication is mild, but the sentence earns its place and stays tight.

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 params, no output schema, and annotations covering the safety profile, the definition supplies what an agent needs: what the funnel returns and that no auth is required. It could be slightly richer with temporal or channel-scope hints, but it is largely complete.

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?

There are zero parameters, so the baseline is 4. The description correctly implies no inputs are needed by framing the tool as a plain funnel readout.

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 resource (acquisition funnel) and the exact metrics returned (clicks and signup conversion per channel). The Korean translation reinforces the same meaning without adding noise.

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?

No when-to-use or when-not-to-use guidance and no named alternatives among the many sibling tools. Usage is only implied by the funnel framing, leaving the agent to infer where it fits versus related member/fleet/status tools.

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