exchange_rates_convert

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

No annotations are provided, so the description carries full burden for behavioral disclosure. It adequately discloses the rounding to 2 decimals, the cross-rate mechanism through RON, and the BNR data source, all of which are meaningful behavioral traits. It does not disclose failure modes or what happens if a currency/date is unsupported, but the core behavior is transparent for a compute-style endpoint.

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?

Three sentences, each earning its place: what the tool does, the cross-rate special case, and the rounding rule. No filler or redundancy. Front-loaded with the core purpose.

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 static-conversion tool with 100% schema coverage and no output schema, the description is quite complete. It covers operation semantics, rate source, special case handling (cross-rates), and output formatting (rounding). The only minor gap is not describing the response format, but outputSchema doesn't exist and the tool is simple enough that only a mild gap remains.

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 schema already documents all 4 parameters (to, from, date, amount). The description adds value by explaining the round-to-2-decimals behavior and cross-rate logic, which gives context for how 'amount' is processed. The date parameter semantics ('defaults to latest rates') is handled by the schema description, and the description doesn't add param-specific detail, but the behavioral rounding context compensates.

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?

Description states a specific verb+resource: 'Convert an amount between two currencies using current BNR exchange rates.' It clearly explains the cross-rate mechanism for non-RON to non-RON conversions and distinguishes from exchange_rates_list (a sibling that lists rates). The BNR source and rounding behavior are concretely specified.

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 description explains the conversion mechanism and that BNR rates are used, giving clear context for when to use it. However, it doesn't explicitly state when NOT to use it or mention alternatives (e.g., exchange_rates_list for viewing raw rates without conversion), though the purpose does imply it's for converting values.

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