get_time_stats

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

No annotations are provided, so the description must disclose behavioral traits. It states 'Get message count distribution,' implying a read-only operation, and mentions 'Timezone-aware bucketing.' However, it does not explicitly state that the tool is non-destructive or discuss permissions or side effects. While the description is reasonably transparent, the absence of annotations means more detail would be beneficial.

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 extremely concise: three sentences with no fluff. The first sentence immediately states the tool's purpose, followed by usage guidance and a key behavioral trait. Every sentence adds value, and the structure is front-loaded for quick parsing.

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 lack of an output schema, the description should clarify what the tool returns. It mentions 'message count distribution' but does not describe the structure (e.g., list of buckets with counts) or how the output format parameters affect it. While the parameter descriptions cover formats, the overall completeness is moderate; the agent might need additional context to fully understand the return value.

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 the burden on the description is lower. The description adds minimal extra meaning beyond the schema: it reiterates the bucket types ('hour, weekday, or day') and mentions timezone awareness. This provides limited additional context but does not significantly enhance understanding beyond the existing parameter descriptions.

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 the tool's purpose: 'Get message count distribution bucketed by hour, weekday, or day.' It specifies the resource (message counts) and the action (get), with clear bucket types. However, it does not explicitly differentiate from sibling tools like 'get_messages' or 'get_stats_overview'. While the purpose is specific and actionable, the lack of distinction from similar tools prevents a top score.

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 explicit usage guidance: 'Use for "when are people most active" type questions.' This clearly indicates the context where this tool is appropriate. It does not mention when not to use it or list alternatives, but the given scenario is sufficient for an agent to understand typical use cases.

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