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

With no annotations provided, the description carries the full burden and does so well: it discloses table A/table B lookup order, automatic consultation of table B for exotic currencies, response fields showing rate, table, and effectiveDate, and non-business-day fallback behavior. These are exactly the operational traits an agent needs to invoke and interpret the tool correctly.

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 the core conversion purpose and then layers on only relevant details about table selection, response fields, and publication fallback. Every sentence contributes useful operational context without repetition or filler.

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?

Given there is no output schema, the description sufficiently explains the relevant response structure by noting that each side of the response shows the rate, table, and effectiveDate used. Combined with its explanation of date handling and fallback behavior, an agent has enough information to call and interpret the tool 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 100%, so the baseline is 3, but the description adds meaningful semantics beyond the schema by explaining that date selects historical rates and that weekends/holidays resolve to the most recent preceding publication. It does not mention no_cache, but the schema already documents that parameter adequately.

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 two currencies using official NBP mid rates, cross-rated through PLN. This clearly separates it from the sibling rate-retrieval tools such as nbp_exchange_rate and nbp_rate_series without requiring the agent to compare schemas.

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?

It gives clear usage context: latest rates by default, historical rates when date is provided, and automatic fallback to the most recent preceding publication on weekends/holidays. It does not explicitly name the sibling tools as alternatives or state when not to use this conversion tool, so it stops short of full routing guidance.

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