get_reference_parameter

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

No annotations are provided, so the description carries the behavioral burden. It discloses that without a paid key only headline free-sample figures are returned, which is important access context. It does not explicitly state read-only behavior or error handling, but for a 'get' tool this is acceptable.

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 no wasted words; the purpose is front-loaded and the limitation follows. Structure is ideal for quick parsing.

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 2-parameter lookup with no output schema, the description covers what is returned (value and citation) and the paid-key limitation. It does not detail error cases or response format, but this is minor given the tool's simplicity.

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?

Schema coverage is 100%, so the baseline is 3. The description adds the notion of 'source-verified' and 'primary-source citation' but does not explain parameter formats beyond what the schema already documents. The schema's example and tax-year enum already handle the semantics.

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 ('Get'), a resource ('U.S. federal financial-planning parameter'), and a key/tax-year lookup scope, and indicates the return includes a value and citation. It is clearly distinguishable from sibling list_reference_parameters (which lists keys) and get_planning_benchmark (a different metric type).

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 this tool is used when you need a specific parameter value by key and tax year. It does not explicitly state alternatives or when not to use it, though the schema's pointer to list_reference_parameters partially compensates. No exclusion guidance is given, making it adequate but not explicit.

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