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

Annotations already establish that this is a read-only, idempotent, closed-world operation. The description adds meaningful behavioral context beyond that: the data source is EIA, the window is the latest 12 months, and omitting state returns all states sorted by price. It does not discuss response shape, but the listed metrics make the return content clear.

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 two sentences, front-loaded with the returned metrics and followed by the key omission behavior. Every phrase contributes useful context without repetition.

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 one-parameter retrieval tool with full schema coverage and no output schema, the description is complete: it lists the metrics returned, the geographic scope, the EIA data window, and the behavior when state is omitted. An agent has enough information to invoke it correctly.

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% and the single state parameter is already documented as accepting a two-letter code, state name, or 'US'. The description adds value by clarifying that omission returns all 50 states and D.C., and that those results are sorted by price.

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 resource and outputs: average residential electricity price, monthly use, monthly bill, and 1- and 5-year price changes for a state, D.C., or the U.S. overall. It is clear what the tool returns, but it does not explicitly differentiate itself from siblings such as check_electric_bill or find_utility_rate.

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 gives useful operational guidance for the optional state parameter: omit it to retrieve all 50 states and D.C. sorted by price. However, it does not explain when to use this tool versus the sibling tools check_electric_bill or find_utility_rate, so selection guidance remains implicit.

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