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

Annotations already declare readOnly, idempotent and non-open-world, so the safety profile is covered. The description usefully adds what the computation produces (totals in h:mm and decimal hours, and an overtime flag above 40 hours), which the agent cannot get from the schema. It does not mention the pay/rate output even though a rate and currency parameter exist.

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 tight sentences: the calculation model is front-loaded and the URL is appended last. No filler or 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 23-parameter tool with no output schema, the description explains the weekly-card model and the shape of the results (h:mm, decimal, overtime flag), which is the key missing context. It omits any indication of the rate/currency pay output, a minor gap given the rich schema.

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 schema already documents every parameter including the HH:MM format and break minutes. The description's mention of start/end/unpaid break per day loosely maps to the params but adds no syntax or default detail beyond the schema. Baseline 3 is appropriate.

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 gives a specific resource (weekly time card) plus the calculation mechanics: start, end, unpaid break per day, totalled as h:mm and decimal hours, with overtime over 40 flagged. This is far more concrete than a restated name. It does not explicitly name the sibling it differs from (e.g. overtime_calculator or time_duration_calculator), so it lands at 4 rather than 5.

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?

There is no explicit when-to-use or when-not-to-use guidance, and no routing to alternatives such as time_duration_calculator (single span) or overtime_calculator. An agent must infer from the mechanics that this is the multi-day weekly option. The usage context is only implied, not stated.

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