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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explains that the five named series are cached and always available, that raw BLS IDs are accepted but may hit rate limits because of shared edge IPs, and that an upstream-limit error means BLS refused rather than the series not existing. This is meaningful behavioral context beyond the schema.

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 three sentences with no filler. Each sentence earns its place: the first states the resource and accepted series, the second explains the warm-set availability, and the third discloses the rate-limit caveat and how to interpret the error. The most important information is front-loaded.

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 single-parameter tool with full schema coverage, the description covers accepted values, availability, and the primary failure mode. It does not describe return payload format or data freshness, but nothing essential to selecting and invoking the tool correctly 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 input schema has 100% coverage and its parameter description nearly duplicates the tool description, including the list of warm series and the raw-ID rate-limit caveat. The description therefore adds no new parameter semantics beyond what the schema already provides, 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 opens with a specific verb and resource: 'Get a key US economic time series from the Bureau of Labor Statistics.' It then enumerates the five supported series, making it immediately clear what the tool does and how it differs from sibling tools focused on country comparisons or indicators.

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 clearly frames the primary use case: retrieving one of five warm, always-available US BLS series. It also warns against relying on raw uncached series IDs due to rate limits. It does not explicitly name sibling tools or state when not to use them, but the US-specific scope provides strong contextual guidance.

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