获取外汇历史汇率

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

No annotations are provided, so the description carries full responsibility for behavioral disclosure. It only states that historical data is retrieved; it does not mention ordering, time range, data source, or response format. This adds little beyond the basic purpose.

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 a single concise sentence that front-loads the primary purpose and includes a relevant use case. Every word earns its place; there is no redundancy or clutter.

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 two-parameter tool, the description communicates the core function adequately, but it lacks explicit guidance on when to use it versus fx_rates and does not describe the return structure. Given the absence of annotations and an output schema, this is minimally complete but has clear gaps.

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 covers 100% of parameters with descriptions for both 'limit' and 'symbol', including supported currency pair codes. The description adds no additional meaning to the parameters, so 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 uses a specific verb '获取' and clearly identifies the resource as '历史汇率数据' for a specified currency pair. The word '历史' distinguishes it from sibling fx_rates, which presumably provides current rates, and the stated purpose of analyzing trends and volatility adds context.

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 implies usage for historical exchange rate analysis ('用于分析汇率走势和波动') but does not explicitly mention alternatives like fx_rates or state when not to use this tool. Guidance is implied rather than explicit.

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