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

Annotations already establish readOnlyHint=true, and the description adds meaningful behavior: skipping weekends and California judicial holidays, plus supporting negative counts. It does not detail output format or edge cases, but it adds useful context beyond the structured fields.

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 with the core function, followed by usage context. The final sentence about hand-counting errors is motivational rather than essential, but it is short and does not meaningfully detract from clarity.

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 simple two-parameter, read-only calculation tool, the description is largely complete: it states the operation, the holiday behavior, and the intended legal use case. The lack of an explicit return-format statement is a minor gap given the absence of an output 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 description coverage is 100%, so the schema already documents both parameters well. The description reinforces the meaning of 'court days' but adds no new syntax, bounds, or format details beyond what the schema provides.

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 opens with a specific verb and resource: 'Add or subtract court days from a date, skipping weekends and California judicial holidays.' This clearly states the operation and scope, and the mention of court days distinguishes it from sibling tools like california_court_day_check and california_court_holidays.

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 gives explicit when-to-use guidance: 'Use this for any period a statute states in court days rather than calendar days,' with a concrete statutory example. It does not explicitly name alternatives or exclusions, so it falls short of a 5, but the context is clear and actionable.

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