tracearr_get_user_stats

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

The description adds meaningful behavioral context beyond the readOnlyHint annotation: it states the aggregation across all owned accounts, the three time windows, and the inclusion of top genres. This transparently reveals the tool's computational scope and output composition without contradicting the annotation.

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, information-dense sentence that covers the primary metrics, aggregation behavior, time windows, and an additional output dimension. Every clause contributes useful information, and the text is front-loaded with the core action.

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 simple parameter list and the presence of an output schema, the description is largely sufficient for correct invocation. It outlines all key behavioral dimensions, though it does not address edge cases like how empty results or non-existent identities are handled, nor does it explicitly advise against using this tool for detailed history.

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 sole id parameter is described only as 'for an identity', which gives minimal semantic meaning beyond the bare string type in the schema. It does not clarify the source or format of the identifier, nor does it connect it to other tools like list_users, but it does establish that the ID represents the identity whose stats are being fetched.

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 identifies the tool as one that returns plays and watch time for an identity, aggregated across accounts and time windows, plus top genres. This specific verb+resource combination distinguishes it from siblings like get_media_stats or get_user_history, which focus on media-level or historical detail.

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 explicit guidance on when to use this tool instead of alternatives. There is no conditional language, no mention of alternatives, and no indication of scenarios where this tool is preferred or not preferred, leaving the agent to infer usage.

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