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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds no behavioral context beyond that: nothing about case-insensitivity of abbreviations, temperature offset handling, or what happens when from_unit/to_unit are incompatible with unit_type. Useful scope information, but no operational behavior disclosed.

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-loads the one-line purpose and then uses a scannable list. The unit inventory is largely redundant with the schema's per-parameter descriptions, which is mild waste, but the total length is short and the structure is clean.

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 no explanation, and annotations cover the safety profile. Combined with full parameter documentation, the definition gives an agent everything needed to call it correctly, with only edge-case behavior (mismatched units, temperature offsets) left implicit.

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%, with each parameter documenting the valid units per unit_type, so the baseline is 3. The description's unit lists and groupings restate what the schema already carries rather than adding constraints such as case sensitivity or invalid-pair behavior.

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 ('Convert between different units of measurement') and immediately enumerates the supported unit families, so the agent knows exactly what domain this covers. The sibling set (calculators, matrix ops, plotting, workspace) contains nothing else unit-related, so disambiguation is immediate.

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 implied by the purpose — an agent will reach for this when it needs a dimensional conversion — but there is no explicit when-to-use guidance and no named alternative (e.g. calc_expression for arithmetic on raw numbers). Adequate but leaves routing to inference.

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