events_series

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

No annotations are provided, so the description must fully disclose behavioral traits. It only describes the output format (time series, bucketed) but fails to mention whether the tool is read-only, what happens with empty results, or any authorization or rate-limit considerations.

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 a single, front-loaded sentence that efficiently conveys the core purpose. It avoids fluff but could be slightly more structured to include key details like required parameters or usage hints. Overall, it earns its place without being overly long.

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?

Given the lack of output schema and the moderate complexity of 5 parameters, the description is insufficient. It does not explain the returned time series format, default behaviors, or error handling. Sibling tools like metrics have richer descriptions, making this one feel incomplete.

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 input schema covers all parameters with descriptions (100% coverage), so the baseline is 3. The description adds minimal value beyond the schema by confirming the bucket unit aligns with the 'unit' parameter. However, it does not provide additional context like expected date format constraints or bucket behavior.

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 it returns a time series of custom events for a website over a date range, bucketed by unit. This distinguishes it from sibling tools like pageviews_series, which focuses on pageview events. The verb 'Time series' implies retrieval, and the resource and boundaries are well-defined.

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 provides no guidance on when to use this tool versus alternatives like explore_event_data or funnel_report. It does not state prerequisites, limitations, or conditions where a different tool should be chosen, leaving the agent without decision support.

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