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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the safety profile is clear. The description adds valuable behavioral context by explaining it combines three EIA series into one lookup and includes week-over-week percent changes, plus the data source. No contradictions with annotations.

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 well-structured with clear sections for overview, usage, exclusions, and return format. Every sentence adds value, and the example output is front-loaded enough for quick understanding without unnecessary verbosity.

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?

Despite having no output schema, the description provides a complete structuredContent example, showing the exact fields and units. It covers data source, frequency, and scope, making the tool's behavior fully understandable without needing additional lookups.

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, and the description explicitly states 'Args: none,' which is appropriate. With no schema to explain, the description correctly notes the absence of arguments, making parameter semantics self-evident.

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 that the tool retrieves U.S. energy market data (WTI crude price, crude oil inventories, natural gas storage) from the EIA. It explicitly lists the three combined series, distinguishing it from siblings like macro_gdp and macro_jobs by naming specific energy metrics.

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 provides an explicit 'When to use' section naming energy-sector context, inflation pass-through analysis, and trading around EIA releases. It also includes a 'When NOT to use' section excluding regional breakdowns, refined products, and non-U.S. data, giving clear guidance on alternatives.

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