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

Beyond the all-false annotations, the description discloses exact return behavior: converted amount, cross rate to six decimals, rounding applied, and the rate date used. It stops short of discussing side-effect/read-only status, but for a conversion tool this is a meaningful behavioral disclosure.

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 sentences with no filler: the first names the action and scope, the second lists the return details. Every clause contributes information.

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 output schema, the description's return-value enumeration is valuable and mostly complete. The rich parameter schema covers date fallback and rounding rules; the only gap is explicit routing versus convert_many for multi-currency batches.

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 100%, so the parameters are already fully documented in the input schema. The description adds no parameter-level meaning beyond what the schema provides, which lands at the baseline 3.

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?

The description states a specific verb and resource: convert an amount between ECB-quoted currencies. It also distinguishes from the convert_many sibling by focusing on a single amount, and from rate-focused siblings by emphasizing conversion output rather than raw rates.

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 opening phrase 'Call this tool to convert an amount...' gives a clear when-to-use trigger. It does not explicitly name alternatives like convert_many or state when not to use it, but the context is unambiguous enough to avoid misrouting.

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