convert_currency

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

With no annotations, the description bears full responsibility for disclosing behavior. It transparently states the use of NBP mid-market rates, the PLN pivot for foreign-to-foreign conversions, and the optional historical date. It does not mention potential edge cases like rate unavailability for certain currencies or errors, but it covers the core operational details beyond what a schema would show.

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?

The description is front-loaded with a clear single-sentence purpose, followed by a concise Args list. Every sentence adds necessary information, with no filler or repetition. The structure is easy to scan and immediately usable by an agent.

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?

The description covers the core functionality, parameter meanings, and the pivot mechanism. It has an output schema (though not shown), so return values are presumably handled there. Missing are notes on error handling or unsupported currency codes, but given the tool's moderate complexity, the description is sufficiently complete for an agent to invoke it correctly.

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 0%, so the description must compensate, and it does. Each parameter (amount, from_currency, to_currency, date) is explained with examples for currencies and an explicit format for date. This adds all the semantic meaning missing from the schema, which only has titles.

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 clearly specifies the tool's function: converting an amount between PLN and another currency or between two foreign currencies using NBP mid-market rates. It distinguishes this from sibling tools like get_currency_rate by emphasizing conversion of an amount rather than just rate lookup.

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 conveys when to use this tool (for conversions) and explains the PLN pivot mechanism, which is essential for understanding how conversions work. It does not explicitly name alternatives or exclusions, but the sibling tool names (get_currency_rate, get_all_rates) imply those are for rate-only tasks, providing implicit differentiation.

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