Add time entry

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

With no annotations, the description carries the behavioral burden. It discloses that the tool persists a timesheet entry and only accepts already-worked time, and it hints at rate/currency conversion with the example '90 euros an hour' -> EUR. However, it does not describe what the tool returns, whether it mutates anything besides creating the entry, or what happens when a project name doesn't match.

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 sentences front-load the purpose and then give the core usage rules without redundant wording. Every sentence adds meaningful information: what the tool does, what inputs are required, and how rate/currency can be expressed.

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 schema documentation covers all 10 parameters in detail, the description doesn't need to repeat them. It provides the essential behavioral model and parameter relationships needed to call the tool correctly. The lack of an output schema is a minor gap, but not critical for a create-style timesheet tool.

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%, so the baseline is 3. The description adds value beyond the schema by explaining the relationship between start, end, and minutes ('start plus either end or minutes'), and by giving a concrete natural-language rate example ('90 euros an hour' -> EUR) that clarifies how string rates and currencies are meant to be supplied.

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 names a specific verb and resource: 'Log ... time you already worked on a project - a timesheet entry.' It clearly distinguishes this from live-timer or time-conversion siblings by emphasizing 'already worked,' and the title 'Add time entry' matches the behavior exactly.

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 states a clear use case: recording already-completed work as a timesheet entry, which implies it is not for ongoing-time tracking or future scheduling. It also explains the required input pattern: 'start plus either end or minutes.' It does not name alternative tools explicitly, but the context is clear enough to guide selection.

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