ksef_lookup_exchange_rate

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

Annotations already declare read-only and idempotent. The description adds meaningful context: the data is 'advisory' and 'requires basis confirmation', which warns the agent about reliability. This goes beyond annotations.

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 extremely concise—one sentence with a semicolon separating purpose and behavioral note. No redundant words; each part adds value.

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?

Despite rich annotations and output schema, the description lacks critical parameter format details. Without this, the agent may misuse the tool (e.g., wrong date format). Behavioral notes are helpful but incomplete for safe usage.

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 0%, so description must compensate. It does not explain currency format (e.g., ISO code), target_date format (e.g., YYYY-MM-DD), or table options (e.g., A, B, C). Parameter names give some hint, but insufficient for correct invocation.

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 states the tool fetches official NBP exchange-rate data, which distinguishes it from sibling tools focused on invoices and VAT. The verb 'fetch' and resource 'exchange-rate data' are specific.

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?

No guidance on when to use this tool versus alternatives. The phrase 'advisory and requires basis confirmation' is about behavior, not usage context. No exclusions or alternatives are mentioned.

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