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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, so safety is covered. The description adds genuinely useful context the annotation lacks: the 1-credit cost. It does not state the output unit (m/s) or how string-typed inputs are coerced.

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?

Two compact clauses: the operation and formula first, the cost parenthetical last. Nothing is padded or repeated from the name.

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 three-parameter deterministic calculation with full schema coverage and annotations, the definition is nearly sufficient. The only real gap is that with no output schema, the return value's identity and units are only implied by the formula.

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% and already documents each parameter's unit and requirement, so the baseline is 3. The formula does add meaning beyond the schema by showing how the three inputs combine (a multiplied by t, then added to v₀), but no extra format or range detail is supplied.

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 ("Calculates final velocity") and disambiguates from the large calculate_* sibling family by naming the exact equation v = v₀ + at. The reader knows precisely what quantity is produced without opening the schema.

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?

There is no guidance on when to pick this over related physics/kinematics siblings such as potential_energy, or on prerequisites like consistent unit systems. The description is a pure definition with no decision context.

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