query_trends

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

With no annotations, the description carries the full burden of disclosing behavior. It states the output is a time series and mentions optional breakdown, but it omits critical details like authentication requirements, rate limits, error handling, what happens when events are missing, or whether results are capped. The agent lacks information about side effects or invocation consequences.

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 two sentences long, perfectly front-loaded with the core action. Every sentence adds value: the first states the primary function, the second specifies the return format and optional feature. No wasted words or redundant information.

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 tool has no output schema and moderate complexity (5 parameters, 1 required), the description covers the return type (time series) and breakdown capability but lacks details on date range handling, default behavior without breakdown, pagination, or errors. It is minimally sufficient for a basic understanding but incomplete for confident invocation, especially without annotations.

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%, with each parameter having a description. The tool description adds overall context ('returns a time series...') but does not enhance understanding of individual parameters beyond what the schema provides. For example, it doesn't explain how 'breakdown' interacts with the interval or how defaults for date_from and date_to work. Baseline 3 is appropriate as the description reiterates schema concepts without significant additional value.

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 that the tool runs a trends query to get event counts over time, returning a time series optionally broken down by a property. The verb 'run' and resource 'trends query' are specific, and the tool distinguishes itself from siblings like list_events (which likely lists raw events) by focusing on aggregated time series data.

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 such as list_events or get_insights. It does not specify prerequisites, typical use cases, or scenarios where this tool is preferred. The agent is left to infer usage from the tool name and schema.

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