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

No annotations are provided, so the description carries the full behavioral burden. It says nothing about which specific unit symbols are accepted, how ambiguity is handled (does 'c' mean Celsius or cup, 'm' meter or mile?), rounding/precision, or the response shape. For a tool with no annotations and no output schema, this is a substantial gap.

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, front-loaded sentence with zero waste. It is efficient, though the brevity contributes to the gaps flagged elsewhere rather than being a virtue in itself.

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?

With no annotations, no output schema, no enums, and only three vague symbol examples in the schema, the definition is not complete enough for reliable invocation. An agent cannot tell which unit identifiers are valid or how ambiguous short symbols are resolved, which is the central risk for a unit converter.

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%, with examples already given for from_unit/to_unit ('c, m, kg' / 'f, ft, lb') and no description at all for value. The description's category list (temperature, length, weight) restates exactly the dimensions those schema examples already convey, so it adds no meaning beyond structured data.

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 ('measurement units') and scopes the domain via the parenthetical (temperature, length, weight). This implicitly separates it from the other convert_* siblings (currency, number base, timestamp, timezone), but it never names them explicitly, so disambiguation is inferred rather than stated.

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 category list (temperature, length, weight) implies when the tool applies, which is a form of scope guidance. However, there is no explicit when-to-use statement, no exclusions, and no routing to the many sibling converters (convert_currency, convert_number_base, convert_timestamp), which an agent would need to choose correctly.

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