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

Annotations already declare readOnly, idempotent, non-destructive, open-world behavior, so the bar is lower. The description adds two real facts beyond them: a hard cap of six benchmarks per call and sparse-data handling ("Missing values remain unavailable"), though the latter is ambiguous about whether values are nulled or omitted.

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?

Three short sentences with the scope constraint front-loaded and no filler. The final sentence is terse to the point of being cryptic, but nothing is wasted.

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 tool with no output schema and an undocumented required parameter, the description should say what a snapshot contains (which benchmarks, units, fields). It omits the parameter entirely and leaves the return shape opaque beyond the count cap.

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 0% and there is one required parameter (category). The description never mentions the category parameter, what "grouped" grouping corresponds to, or how "all" behaves versus the specific enum values, so it does not compensate for the coverage gap.

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 and resource ("Read a grouped snapshot of ... energy benchmarks") and bounds the result set ("at most six"). It does not distinguish itself from siblings such as energy_get_latest or energy_compare, so an agent must still infer which read tool to pick.

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?

"Catalog enumeration and bulk extraction are outside this plugin" gives a negative boundary that implicitly routes to energy_search_catalog, but no positive when-to-use rule, no prerequisites, and no comparison to the other price/curve tools is offered.

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