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

Annotations already cover the safety profile (readOnly, non-destructive, closed-world), so the bar is lower, yet the description adds real substance: the computation runs backwards from the needed date against the actual factory shutdown rather than the statutory holiday, and it discloses that the result reports a collision with the closure plus the latest safe order date. With no output schema, this return-value disclosure is genuinely useful.

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?

Front-loaded with the usage trigger, followed by the mechanism and the output. Three dense sentences with little waste, though the middle sentence's mechanism detail could be tightened.

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?

No output schema exists, so the description carries return-value burden and does so ('says whether the plan collides with the closure and gives the latest safe order date'). Inputs are fully schema-documented and annotations cover safety, leaving nothing an agent needs missing.

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 mode, arrival_date, transit_days and production_days. The description's 'by sea, air or express' loosely maps to the mode enum but adds no format or default detail beyond the schema, making this a baseline case.

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?

States a specific verb and resource — planning an order around the Chinese New Year shutdown — and enumerates the concrete questions it answers (latest order date from China, CNY shipping cutoff, whether goods arrive in time). This is clearly distinguishable from siblings like compare_sea_and_air or estimate_landed_cost.

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?

Explicit trigger conditions are given ('Use for any question about the latest date to order from China... or whether goods arrive in time around the holiday'), which routes the agent well. It stops short of naming a sibling alternative or an explicit when-not-to-use case, so it is clear context rather than full routing.

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