get_exchange_rate

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

Annotations already declare readOnlyHint=true, openWorldHint=true, and idempotentHint=true. The description adds no behavioral context beyond the basic function, such as data freshness, scope of currencies, or response format.

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 concise, with one sentence and a parameter definition. The inclusion of strategy and examples tags adds structure but is not excessive. Each part serves a purpose.

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 one parameter and an output schema, the description adequately explains the function and parameter. However, it omits details about the output structure, which is covered by the output schema per rules, but additional context like 'major' currency definition would improve completeness.

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 parameter 'base' is described as 'Base currency (default CNY)', which adds meaning beyond the schema's default value. However, no valid values or constraints are provided, and schema description coverage is 0%, so the description only partially compensates.

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 'Get major currency exchange rates' which clearly indicates the tool's purpose. However, it does not differentiate from the sibling tool 'get_forex_quote', which likely provides similar data, reducing clarity on when to use each.

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 includes a strategy tag suggesting direct invocation for FX rates, but no explicit guidance on when to use this tool versus alternatives like 'get_forex_quote'. There is no mention of prerequisites or exclusions.

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