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

With no annotations, the description carries the full burden. It does disclose the underlying method (90-minute cycle model) and the nature of the result (recommended hours by age), which is useful since there is no output schema. However, it never explains how the bed/wake inputs interact (both are optional), what latency minutes represent, or what happens if neither or both are supplied.

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 compact sentence that front-loads the domain tag and the core function, then adds the cycle model and the age-based output. No filler, though the bracketed guide tag adds little actionable information.

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 3-param calculator with no annotations and no output schema, the description covers purpose and return content reasonably well. It falls short on the one undocumented parameter (latency) and on the bed/wake interaction model, which an agent would need in order to call it correctly.

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 67%: bed and wake are only labeled "HH:MM" and latency has no description anywhere. The description hints at the input model (either a wake time or a bedtime is used to derive the counterpart), which slightly clarifies how bed/wake are used, but latency is entirely undefined and the mutual exclusivity of bed/wake is left to inference.

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 (計算/calculate) and resource (建議就寢或起床時間/suggested bedtime or wake time) plus the method (90-minute sleep cycles) and secondary output (age-based sleep hours). No sibling tool competes for sleep-timing calculation, so the agent can identify it unambiguously from the name alone.

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 by stating what it computes, but never says when to prefer it, what prerequisites exist, or what to do with edge cases. No alternatives are named, though no sibling tool performs a similar function, so the cost of that omission is low.

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