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

With no annotations, the description carries the full burden and does well: it discloses annualization methodology, month-by-month bill-credit cliff modeling, the exclusion policy, per-item URL citation, and a licensing constraint (free non-commercial with attribution, Pro for commercial). It omits permissions/auth mechanics and any rate limits, but the modeling behavior is unusually well explained for an unannotated tool.

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 differentiator (annual cost, not the 1,000 kWh price) before the methodology and caveats, and each sentence is information-dense. The licensing sentence is somewhat tangential but still earns its place for commercial users.

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 10-parameter ranked-list tool with no output schema, the description covers the ranking basis, exclusion semantics, return shape (items with urls), and usage rights. Combined with 80% schema coverage it gives an agent enough to call correctly, though it doesn't explain pagination or default limit behavior.

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 80%, so the schema already documents most parameters (kwh, term, months, utility, EV fields). The description reinforces include-driven exclusions and the annual-cost vs sticker-price distinction but adds no syntax or default details beyond the schema. Baseline 3 is appropriate.

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 (Rank), resource (every electricity plan), and scope (a Texas utility, by ESTIMATED ANNUAL COST). The clause 'not just the 1,000 kWh price' actively distinguishes it from generic cheapest-price tools like electricity_cheapest, so an agent can route correctly without opening either schema.

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?

Explicitly states when the tool's default behavior applies and what it excludes (variable, prepaid, time-of-use, short-term <6 month) 'unless requested', which maps to the include parameter. It lacks explicit routing to sibling tools, but the context is clear enough to select it.

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