rates_us_treasury

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

With no annotations, the description carries the full transparency burden. It discloses the cost ($0.005 USDC per call), upstream latency (~10s), caching behavior (6-hour cache), and a response field (meta.fetchedAt). However, it does not explicitly state that the tool is read-only or non-destructive, which is implied but not confirmed.

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 paragraph that front-loads cost and purpose, then adds details and use cases. It is reasonably concise, though the list of use cases could be streamlined as it partially repeats the 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 zero-parameter tool without an output schema, the description covers the data source, output content (yields for 13 maturities, curve date), caching, cost, and use cases. It is sufficient for an agent to understand what the tool returns, though listing the exact maturities 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 tool has zero parameters, so the baseline is 4. The description adds value by explaining what the output contains (13 maturities, curve date) beyond the empty schema, partially compensating for the lack of an output schema.

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 the tool retrieves the latest US Treasury daily par yield curve for maturities 1M-30Y, specifying the data source (US Department of the Treasury) and scope (13 maturities). This distinguishes it from sibling tools like crypto_gas or fx, which cover different domains.

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 lists use cases (interest rate benchmarks, bond analysis, etc.) but does not explicitly state when to use this tool versus alternatives or provide any exclusion criteria. While sibling tools are distinct, no comparative guidance is given.

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