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

Annotations already cover read-only, non-destructive, closed-world behavior, but the description adds a genuinely useful safety trait the annotations cannot express: it never takes payment and only returns a link. It still does not state that the adult/18+ verification hinges on the tap token or what happens when the token is empty.

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?

Three short sentences, front-loaded with the trigger, followed by exclusions and then the key safety constraint. No filler and no repetition of schema content.

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, read-only link-returning tool with full schema coverage and annotations, the definition covers trigger, exclusions, and the no-payment guarantee, and it sketches the return value. Only the dependency on a valid 18+ tap token for eligibility 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?

Schema description coverage is 100%, so both the tap token and the plan enum are fully documented in the schema itself. The description adds no extra meaning about parameter usage, which is acceptable at this coverage level but earns only 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 states a concrete trigger (an adult wants to buy or upgrade) and names the resources (team plan, business package), and it clarifies the output is a link rather than a purchase. It does not, however, distinguish itself from link-returning siblings such as get_app_link or account_link.

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 gives an explicit positive trigger and explicit exclusions: not for medical questions, emergencies, crisis, or general meditation chat. What it lacks is routing to an alternative when the request is one of those excluded cases, so the agent knows what to avoid but not where to send the user instead.

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