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

Annotations already cover the safety profile (readOnlyHint, openWorldHint=false, destructiveHint=false), so the description earns credit for what it adds: feed_ready is false while the Growth Snapshot deep scan is still building, and credits only appear once metering is live. These state nuances explain why fields may be absent, which is genuinely useful beyond the annotations.

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 dense sentence front-loads the core action ('Confirm the AfterLaunch key works') before enumerating outputs. It is slightly run-on with the parenthetical and the trailing credits clause, but no sentence is wasted.

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 output schema, the description carries the burden of explaining return values, and it does list the key returned fields (scopes, tier, trial_ends_at, onboarding/feed_ready, credits) plus the condition under which some are populated. Reasonably complete for a zero-parameter diagnostic, though the field list is neither exhaustive nor typed.

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 the baseline is 4. The description appropriately spends its words on the response shape instead, which is the right allocation for a parameterless tool.

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 ('Confirm') and a specific resource (the AfterLaunch key and its binding to a product run), then enumerates the fields returned: scopes, tier, trial_ends_at, onboarding and credits. An agent can tell this apart from get_enrollment or get_business_context, though it never explicitly names a sibling.

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?

Usage is implied rather than stated: 'Confirm the AfterLaunch key works' suggests a diagnostic/bootstrap check, but there is no explicit when-to-use, when-not-to-use, or alternative tool named. An agent must infer the trigger condition.

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