Summarise tracked time

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds behavioral context that this tool computes totals directly from time entries rather than relying on the Reports API, which implies different data source and plan compatibility—valuable beyond annotations.

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?

A single, front-loaded sentence with no filler. It efficiently communicates the tool's purpose and edge case without redundancy.

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 summary tool with six well-documented params and no output schema, the description conveys the core functionality and differentiating context (free plan). It does not specify output format or pagination, but given the tool's simplicity and annotation coverage, the description is sufficiently complete.

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 all parameters described in the input schema. The description adds minimal parameter semantics—it echoes group_by options (project, task, day, tag) but omits 'description' and doesn't introduce syntax or format details. Baseline 3 is appropriate since the schema carries the parameter documentation burden.

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 function: computing totals per project, task, day, or tag for a period. It differentiates itself from sibling report tools by noting it works on the free plan where the Reports API is unavailable, establishing a specific scope and alternative approach.

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 implies when to use this tool (when Reports API is not available or when working with free plan) but does not explicitly name alternatives or provide a when-not-to-use statement. It offers clear contextual guidance without explicit exclusions.

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