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

There are no annotations, so the description carries the behavioral burden. It does disclose useful behavioral context: the data is 'Delayed' and sourced from 'official FRED'. However, it does not mention units, update cadence, or whether 2s10s is a spread, leaving some behavioral ambiguity.

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 compact, front-loaded phrase that uses every word meaningfully: delay status, source, and exact tenor composition. There is no filler or redundant restating of the schema.

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 with an output schema present, the description gives enough context: source, latency, and exact series. The only real gap is explicit usage routing, which was already penalized in usage guidelines, so the tool remains adequately specified for an agent to call it confidently.

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 there is nothing for the description to clarify beyond the schema. This earns the baseline of 4; no parameter documentation is needed or expected.

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 names the exact financial resource: official FRED 10Y / 2Y / 2s10s yield curve data. Even though it lacks an explicit verb, the tool name 'get_yield_curve' plus this resource specificity makes the purpose unmistakable and distinct from sibling tools.

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 the tool should be used when the agent needs FRED 10Y/2Y/2s10s curve data, but it does not explicitly state when to use it versus alternatives or when not to use it. With many market-data siblings, some explicit routing guidance would strengthen this dimension.

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