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

The annotations already declare readOnlyHint=true, so the safety profile is known. The description adds the 'data caveats' aspect and instructs to call only once, but it doesn't disclose more subtle behaviors like whether repeated calls return stale data or if any side effects occur beyond a read.

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?

The description is two concise sentences, front-loaded with the core purpose and immediately followed by actionable usage guidance. Every sentence earns its place, with no redundancy.

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 simple one-parameter read-only tool, the description adequately covers what it does, when to call it, and why it matters. It doesn't describe the return format, but no output schema exists and the response is a straightforward context object. The mention of 'data caveats' hints at nuances, which is sufficient.

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 schema description for the only parameter 'site' is fully covered ('Site handle from list_sites.') and the description adds no additional meaning about the parameter. Since schema coverage is 100%, the baseline of 3 is appropriate.

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 clearly states the tool's verb and resource: 'Get a site's timezone, currency, locale, and data caveats.' This distinguishes it from sibling tools like get_audience or get_funnel, which focus on specific metrics.

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?

The description includes explicit guidance: 'Call this once before answering questions so you interpret dates and money correctly.' This tells the agent when to use it, though it doesn't mention alternatives or exclusions explicitly. It implies this is a prerequisite for other data-getting tools.

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