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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. Beyond that the description discloses that results are preaggregated, paginated via page.next_cursor, echo the applied limit, and represent event volume/coverage rather than custom-field values — meaningful behavioral context. It stops short of stating retention limits or rate limits, so not a 5.

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 purpose is front-loaded, followed by filtering scope, pagination rule, and exclusions with an alternative — a logical order with no filler. It is dense but every sentence carries information; the only slight cost is that five packed clauses demand careful reading.

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 an 8-parameter read tool with no output schema, the description supplies what an agent needs: what a point represents, how paging works, that the applied limit is echoed, and what the tool will not return. Without an output schema, a little more on response shape would have been ideal, but the essentials are covered.

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 every parameter including limit bounds, cursor, date formats and enums is already documented in structured form. The description adds only the framing that eventKind/eventName are optional narrowing filters and ties eventName provenance to get_game_telemetry_analytics, which is modest value over the schema.

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?

"Paginated preaggregated 30-minute or daily telemetry counts" names the verb (read), the resource (telemetry time series), the granularity options, and the intended analysis. It then distinguishes itself from siblings twice: "Compare performance values with bounded event-analytics requests instead" and "This tool never reads or returns raw events."

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 states the intended use cases (trend, release and regression comparisons), an explicit exclusion ("not FPS or other custom-field value distributions"), and names the alternative for performance values (bounded event-analytics requests). It even gives a paging discipline rule: follow page.next_cursor only while more points are needed for the current conclusion.

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