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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds nothing beyond that - no note on the 60-day window, result shape, or how the chart output behaves - so it does no behavioral work of its own.

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?

It is short and front-loads the retrieval purpose, but the second sentence is filler with a grammatical error and conveys no information. Roughly half the description does not earn its place.

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?

The tool has 6 optional parameters, nested objects, and multiple near-identical analytics siblings, yet the description provides no differentiation or usage context. Output schema and annotations cover return values and safety, but the selection-critical context is missing.

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 filters, metrics, group_by, date_range, workspace_id, and chart_dimension are already fully documented in the schema. The description adds no parameter meaning on top of that, which is the baseline 3 case.

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?

It names a verb and a resource ('retrieves viewer analytics data'), but the resource is generic and does not distinguish this tool from the many analytics siblings (analytics_aggregated_data, analytics_breakdown_data, insights_chart_data, retrieve_analytics). Nothing signals the chart/time-series nature implied by the name, so an agent cannot tell them apart without opening the schema.

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?

There is no when-to-use guidance and no mention of alternatives. 'This endpoint is use for deep insights on the analytics data' is a vague marketing phrase, not a condition that would help an agent choose this tool over analytics_aggregated_data or analytics_breakdown_data.

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