tokmeter_heatmap

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds useful behavioral context: data is built from individual records, and the default all scope covers the last 14 days, though it does not describe output structure or pagination.

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 front-loaded and mostly efficient, leading with the core visualization purpose. There is some mild redundancy between the first and third sentences about understanding work patterns and peak usage times.

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 heatmap tool with fully documented parameters and no output schema, the description covers purpose, scope default, and intended use. It could be more complete by briefly describing what the heatmap output contains, but the core information an agent needs is present.

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 schema already documents all four parameters and enum values. The description only adds one extra parameter detail beyond the schema: that the default all scope covers the last 14 days. This is useful but not enough to exceed the baseline for fully documented schemas.

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: visualize activity patterns as a heatmap by hour and day, showing cost and token intensity. It is clear what the tool does, though it does not explicitly differentiate itself from sibling tools like tokmeter_timeline or tokmeter_pulse.

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?

It explicitly says to use this tool to understand work patterns and peak usage times, giving clear context for selection. It does not state when not to use it or name alternative sibling tools for related analyses.

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