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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds useful context: keyless access, live sourcing from chinamoney.com.cn, and the 'cheap' nature of the call. It does not contradict annotations and provides extra behavioral detail beyond the structured hints.

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?

Two sentences with zero waste. The first sentence front-loads the core purpose and output, the second provides the alternative and key operational details. Every clause earns its place, and the structure is immediately scannable.

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 zero-parameter, read-only tool, the description fully covers what an agent needs: what it returns, where data comes from, auth requirements, and the sibling distinction. Without an output schema, it adequately describes the expected result. No critical information is missing.

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 tool has zero parameters, so the schema carries no semantic burden. Per the rubric, 0 params warrants a baseline of 4. The description mentions the output fields (1Y/5Y rates and official date), which is relevant but not parameter-specific, so no extra credit beyond the baseline is warranted.

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 ('print') and resource (most recent PBOC LPR 1Y/5Y), explicitly noting it excludes the 12-month history, which clearly distinguishes it from the sibling tool china_lpr. The scope is precise and unambiguous.

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 explicitly tells the agent to use china_lpr instead if the trend over time is needed, providing a clear alternative and the condition for choosing it. Also notes it's a 'cheap single-row call', implying suitability for quick latest-rate lookups. No prerequisites are required, and keyless access is stated.

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