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

Annotations already establish read-only, idempotent, open-world, non-destructive behavior, so the description adds value with new facts: source failure is "noted, not fatal" (partial-failure resilience), the data is EIA public domain, and it is informational only, not trading advice. It doesn't specify latency, caching, or result limits, keeping it below a 5.

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?

Front-loads the deliverable and the benchmark list before the use case, resilience note, and disclaimer. Mostly every sentence earns its place, though the branding phrase "Premium synthesis over the EIA domain" adds little operational value.

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?

With a single optional parameter, no output schema, and annotations covering the safety profile, the description still spells out the returned fields (latest level and date, 1-year change, percentile, trend direction) and failure behavior. An agent has everything needed to call and interpret it.

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 description coverage is 100% and the lone lookback_days parameter is fully documented in the schema with its default, min, and max. The description never mentions the parameter, so it adds no meaning beyond the schema — baseline 3.

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?

States a specific deliverable: a one-call US energy snapshot covering WTI (Cushing), Brent, and Henry Hub, each with derived context (level, 1-year change, percentile, trend). This precisely distinguishes it from the domain-specific siblings like eia_oil_supply or eia_natural_gas, which serve single slices rather than a synthesized three-benchmark view.

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?

Gives a clear use case ("what is oil/gas doing right now, and is it historically high or low" in a single call) and frames itself as a synthesis layer, which implies using it instead of chaining multiple EIA calls. It does not explicitly name alternative sibling tools or exclusions, so it stops short of a 5.

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