get_latest_exchange_rates

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

Annotations already provide readOnlyHint=true and openWorldHint=true. The description adds that rates are 'latest' and explains filtering behavior, but does not elaborate on the open-world nature or data source. It does not contradict 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 three sentences with no filler. The purpose is stated first, then filtering behavior, then default behavior. Every sentence adds value, and it is appropriately sized for a simple tool.

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-only tool with 2 parameters and no output schema, the description covers the essential aspects: what it returns and how to filter. It could mention that the rates are relative to base_currency and note the open-world hint, but it is largely sufficient.

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. The description repeats the schema information for symbols without adding new details, and for base_currency it adds nothing beyond the schema description.

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 it returns the latest exchange rates for specific currencies, with a clear verb and resource. It distinguishes itself from sibling tools like convert_currency_latest and get_historical_exchange_rates by focusing on rates rather than conversion or historical data, but does not explicitly differentiate.

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 explains that symbols can filter results and if omitted all currencies are returned, which is a usage guideline. However, it does not mention when to use this tool over other siblings like conversion tools or historical rates, leaving the agent to infer from context.

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