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

With no annotations, the description carries the full burden, and it does disclose two meaningful traits: the key is validated server-side and the call produces an api_key as a side effect of activation. It still omits whether the call is idempotent, what happens on an invalid or already-used license, and whether it consumes a license seat.

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 sentence front-loads the action and the payoff with zero filler; the parenthetical about server-side validation earns its place as the only behavioral detail offered.

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 two-parameter tool with an output schema, the description covers the essentials and even names the returned artifact (api_key). Failure modes and repeat-call behavior are the remaining gaps, but nothing critical to invoking it correctly is missing.

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?

Schema description coverage is 100%, so both parameters are already documented, including the email-binding behavior. The description's mention of the license key adds no syntax or format detail beyond the schema, so this sits at the baseline.

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 (activate), the resource (a Gumroad license), and the concrete outcome (a GoAI Moat api_key). The siblings listed are unrelated analytics tools, so there is no real ambiguity to resolve; the only friction is that the tool name 'check_license' understates that this is an activation, not a read-only check.

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?

There is no explicit when-to-use or when-not-to-use guidance, no prerequisites (e.g. must own a Gumroad purchase), and no alternatives named. The only implied context is that the input is a purchased license key, which is already conveyed by the schema.

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