Convert units

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds one genuine behavioral trait — that cross-category conversions are rejected — but says nothing about case sensitivity, accepted unit spellings, or how temperature offsets are handled, which are the real failure modes here.

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 tight sentences with zero waste; the capability and its category scope are front-loaded, and the constraint follows immediately.

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 values need not be explained, and all three parameters are documented. What remains thin is the accepted unit vocabulary and its normalization rules — the description names categories but not the strings an agent may pass.

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 the schema already gives unit examples ('km, kg, mL, J or C'), so the baseline is 3. The description adds no syntax or format detail (e.g., whether unit strings are case-sensitive or what aliases exist) beyond what the schema provides.

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 ('Convert') and resource ('a value between units') and enumerates the supported measurement families (length, mass, time, volume, energy, temperature), which lets an agent judge scope immediately. It does not explicitly differentiate itself from the sibling tools, though that difference is obvious from the domain (they are chemistry calculations).

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?

Usage is only implied — an agent infers 'use this when you need a unit conversion.' The sentence about refusing cross-category conversions acts as a negative condition but is phrased as an error behavior, not as guidance, and no alternatives or prerequisites are named.

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