Time report

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

No annotations are provided, so the description carries the full behavioral burden. It mentions grouping and per-currency totals but does not explicitly disclose read-only behavior, the clamping behavior on the free tier, the default unbilled_only behavior, or the output shape. These gaps are partially covered by the schema, but the description itself adds little beyond a summary.

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, front-loads the main purpose, and avoids excessive detail. The phrase '(group by)' is slightly redundant, but overall every sentence contributes useful 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?

For a reporting tool with six parameters, a rich schema, and no output schema, the description provides the essential context: period-based timesheet totals, grouping options, and the plain-total fallback. It does not spell out return values, but the format parameter and schema descriptions cover the remaining details.

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 baseline is 3. The description adds value by explaining why group_by exists ('hours per project, how much to bill') and what omitting it produces ('the plain total per currency'), which goes beyond the schema's parameter names and enums.

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 resource ('Timesheet report') and the core output: total tracked hours and billable money for a period, optionally grouped by project, day, task, or tag. It is clear enough to distinguish from sibling tools like invoice_summary or forecast, though it uses a noun phrase rather than an explicit verb like 'generate' or 'show'.

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 gives practical guidance for the group_by parameter ('Omit group_by for the plain total per currency') and implies a billing/timesheet use case. However, it does not explicitly say when to use this tool instead of alternatives such as invoice_summary or forecast, nor does it state any exclusions.

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