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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds real value beyond that: the data source (EIA Form 861) and the vintage semantics (annual average paid, not current plan offers), which prevents misreading the number as a live tariff.

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, zero filler. The search scope and return fields come first, with the important caveat about annual averages front-loaded at the end where it will be read before calling.

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?

There is no output schema, so the description carries the return-value burden and does so by naming both returned fields and the source dataset. It stops short of explaining behavior on partial or multiple matches, which is the main remaining gap for a name-search tool.

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 baseline is 3. The description earns a bump by giving concrete query examples ('PG&E', 'Oncor', 'Duke Energy') that demonstrate the initials/fuzzy-name matching the schema only vaguely labels as 'Utility name or initials'. The optional state parameter is left entirely to the schema.

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 verb+resource (search U.S. electric utilities and retail providers) and specifies exactly what comes back: average residential price per kWh and customer count. It implicitly separates itself from check_electric_bill and get_state_electricity_stats by being a per-utility lookup, but never names those siblings.

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 line 'These are what residential customers paid on average over the year, not current plan offers' gives a clear when-to-use and when-not-to-use boundary for this lookup. It does not, however, route the agent to check_electric_bill or get_state_electricity_stats when those are the better fit.

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