get_exchange_rate

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

With no annotations, the description carries the burden of behavioral disclosure. It adds useful context (source: NBP, type: mid rate, date options), but does not describe potential error conditions, handling of non-trading days, or response format. This is a read operation, but lacks deeper transparency.

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 a single sentence that is front-loaded with the key action and object. It contains no filler or redundant 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?

Although no output schema exists, the description adequately covers the core purpose, the source, and the date parameter. However, it omits details about the response structure and error cases, which is acceptable given the tool's simplicity but leaves minor gaps.

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?

The input schema provides complete descriptions for both parameters (code and date), covering 100% of the parameter documentation. The description merely paraphrases the date flexibility already in the schema and adds no new parameter-level detail, so it meets the baseline.

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 uses the specific verb 'Get' and clearly identifies the resource as the 'NBP mid exchange rate for a currency against PLN', which distinguishes it from sibling tools like convert_currency. It also specifies the date scope (today or a specific date), making the purpose unambiguous.

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 implies the tool is for fetching NBP mid rates but does not explicitly state when to use it over alternatives like convert_currency or check_vies. There is no mention of excluded scenarios or prerequisites, so the guidance is only implied.

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