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

Annotations already establish readOnlyHint=true, idempotentHint=true, and openWorldHint=false, so the safety profile is covered. The description adds useful boundary semantics ("after from" and "up to and including to") and the Swedish business-day scope, but says nothing about the mode parameter or how Swedish holidays/weekends are treated.

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 states the action, the scope, and the range boundary efficiently.

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?

The tool is simple and annotations cover the safety profile, but the description omits any explanation of the mode enum values and gives no return-value clarification. For an agent choosing between bank and work modes, the definition is only minimally 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 description coverage is 100%, so the baseline is 3. The description adds boundary semantics for from/to, but does not explain the mode parameter ("bank or work") beyond what the schema already says, leaving a meaningful parameter semantic gap.

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 verb ("Count") and resource ("Swedish business days") plus a clear range boundary. It distinguishes itself from the sibling add_business_days by verb, but does not explicitly name or contrast that alternative.

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 usage (count business days between two dates) but provides no explicit when-to-use guidance or alternatives to add_business_days, swedish_holidays, or swedish_date_info. The context is clear enough to infer basic use, but not enough to route confidently among siblings.

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