get_exchange_rate

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

There are no annotations, so the description must carry the behavioral disclosure burden. It does not mention whether it returns current or historical rates, how errors (e.g., invalid currency codes) are handled, whether data is real-time or delayed, or any rate limits. The only behavioral cue is 'Get', which implies read-only, but that is not explicitly stated.

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 very concise: 'Get the exchange rate (환율).' It is front-loaded and contains no filler. The Korean translation is redundant but not distracting. For such a simple tool, a one-sentence description is appropriately sized, though it could have slightly more detail without losing conciseness.

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 read tool, the description plus schema gives a basic understanding. However, with no output schema and no annotations, the agent lacks information about the return value's structure (e.g., numeric rate vs. nested object) and the effect of the optional date_time parameter on the output. It is adequate but not complete.

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 descriptions for all parameters (base_currency, quote_currency, date_time) and covers 100% of them. The description adds no additional parameter context, e.g., format of currency codes or the meaning of date_time. Since schema coverage is high, the baseline of 3 is appropriate.

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 clear action ('Get') and resource ('exchange rate'), differentiating it from siblings like get_orderbook or get_prices. However, it lacks specificity about the currency pair (base/quote), though the schema supplies that. It is not merely a tautology and conveys the core function.

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 provides no guidance on when to use this tool versus alternatives. It does not mention any prerequisites, intended scenarios, or situations where other market data tools (e.g., get_prices) would be more appropriate. The usage is only implied by the name.

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