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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so safety is fully covered. The description adds only a thin input list and a placeholder-shaped "Returns: {input}" that conveys no real behavioral information such as rounding, precision, or error behavior.

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?

One tight sentence of purpose followed by useful domain hints, but "Inputs: value, from, to" merely restates the schema and "Returns: {input}" is an unrendered template artifact that adds noise rather than meaning.

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?

A simple 3-parameter read-only converter with a full output schema needs little prose, and the description covers purpose and units. However it omits the duplicate-sibling disambiguation and contains a unit list inconsistent with the enum, so it is only adequate.

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 the baseline is 3, but the description lists arcminutes and arcseconds as convertible units while the schema enum only permits degree, radian, gradian and turn. That mismatch actively misleads an agent about valid inputs, dropping it below baseline.

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 (convert) and resource (angle) and enumerates the exact unit set, which distinguishes it from convert_area, convert_volume and the other convert_* siblings at a glance. An agent can pick this tool without opening the 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?

"Use for math, navigation, surveying" gives domain context but no when-not guidance and no disambiguation from the near-identical sibling calculate_angle_convert. Usage is implied rather than stated.

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