science.half_life

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

Annotations already declare readOnly/idempotent/closed-world, so the safety profile is covered. The description adds value beyond them by disclosing the numerical method (mpmath, 50 digits) and output precision (30 significant digits), which an agent needs to trust the result.

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 purpose then formula, then constraints, then output behavior — good ordering with little waste. The closing sentence repeats the unit-consistency rule already stated mid-paragraph, which is mild 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?

An output schema exists, so return structure need not be spelled out, and the description still usefully notes the fraction is returned alongside. For a 3-parameter tool with zero schema descriptions, the constraints and precision disclosure make it callable without guesswork; only input formatting examples are 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 coverage is 0% — all three parameters are bare strings with only titles — so the description carries the full burden and does so: initial_amount and half_life must be positive, elapsed_time is a Decimal string ≥ 0, and half_life/elapsed_time must be unit-consistent. It does not give a format example or explain what unit initial_amount is expressed in, leaving a small 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?

States a specific verb and resource ('방사성 붕괴로 남은 양을 계산한다') and backs it with the exact formula N(t) = N0 x 0.5^(t/T), so an agent knows precisely which computation this performs. It is unambiguously distinct from the other science.* calculators (bragg, nernst, ideal_gas, etc.).

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?

Gives explicit preconditions and a clear prohibition: half_life and elapsed_time must share the same time unit, and '단위가 다른 반감기와 경과 시간을 섞으면 안 된다.' No competing sibling is named, but for a self-contained formula tool the applicable context is stated plainly.

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