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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering the safety profile. The description adds useful behavioral context beyond annotations by specifying the interactive chart and short summary return format, and by framing the output as a trend versus goal.

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?

Two compact sentences communicate the core behavior, the supported time windows, and the return format without redundancy. The main action is front-loaded, and every clause earns 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?

For a read-only tool with one optional parameter, a complete schema, and an output schema, the description provides all necessary selection and invocation context. The interactive chart and summary are specified, and no additional behavioral caveats are essential.

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%, and the sole parameter 'range' is fully documented with an enum and default. The description repeats the allowed range values but adds no new meaning beyond the schema, so the baseline score of 3 applies.

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 states a specific verb and resource: a visual step-count trend compared to a goal. It clearly differentiates this from sibling tools like show_week_sleep or show_week_macros by naming the exact metric and view type.

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 gives clear context for when to use the tool: when the user wants a step-count trend versus goal over 7d, 30d, 90d, or 1y. It does not explicitly name alternative tools or exclusion criteria, but the context is unambiguous for a simple visualization tool.

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