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

Annotations already declare read-only/idempotent/non-destructive, and the description adds substantial behavioral context: pagination via page.next_cursor, the response returning the applied limit, what the points do and do not represent (volume/coverage, not FPS or custom-field distributions), and that raw events are never read or returned.

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?

Front-loaded with the core purpose and scope, then caveats. Six sentences is on the longer side, but each adds a distinct constraint (grain, narrowing, pagination discipline, semantic scope, routing, raw-event exclusion).

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?

No output schema exists, yet the description explains what the response contains (points, next_cursor, applied limit), and covers grain, filtering, and boundaries. An agent has everything needed to call and interpret it correctly.

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 coverage is 100%, so the schema already documents all 8 params and 3 is the baseline. The description adds meaning beyond the schema by clarifying the granularity options (30-minute vs daily), the event namespace/name narrowing, and the limit/cursor relationship to pagination.

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 and resource: preaggregated 30-minute or daily telemetry counts. It differentiates from siblings by scoping to volume/coverage trends and explicitly pointing performance-value comparison to event-analytics requests.

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?

Gives clear context (trend, release, regression comparisons) and narrowing options, plus a pagination-following rule and a routing hint away from performance queries. The alternative is described generically as 'bounded event-analytics requests' rather than naming the specific sibling tool, so routing is slightly less than explicit.

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