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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so the safety profile is covered. The description adds that output is power in kW plus apparent power in kVA, but with an output schema present that is largely restating structured data; nothing is said about the formula assumptions (e.g. whether cos_phi applies to three-phase).

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?

Four short, front-loaded sentences with the computing action first. 'Use for electrical engineering' is near-filler and the list_bundles pointer is tangential, but there is no bloat overall.

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 an idempotent, read-only pure calculation with a fully described schema and an output schema, the definition covers inputs, phase handling, and return units. The only real gap is which sibling calculator to prefer, which is a routing concern rather than a completeness gap.

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 each property already carries its own note ('Amps', 'Volts', 'Power factor'), so the description simply re-lists the same four inputs without adding units, ranges, or defaults. Baseline 3 applies when the schema does the heavy lifting.

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 ('Compute electrical power') and narrows scope to single/three-phase circuits, which separates it from generic converters like calculate_power_unit_convert. It does not, however, distinguish itself from close electrical siblings such as calculate_ohms_law or calculate_cable_section_electrical.

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?

'Use for electrical engineering' is a domain label, not guidance on when this tool is the right choice versus ohms_law, electricity_cost, or power_unit_convert. No exclusions, prerequisites, or alternatives are named; the pointer to list_bundles is a catalog reference, not tool-selection advice.

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