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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered without prose. The description adds a small amount of behavioral evidence via worked examples showing negatives and decimals map to a non-negative result, but says nothing further about output format or domain limits (e.g., complex numbers).

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 short sentences, the operation front-loaded, then examples that earn their place by demonstrating sign and decimal handling. Zero waste for a tool of this simplicity.

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?

An output schema exists, so return-value explanation is unnecessary, and a one-parameter closed-world math operation needs little else. The only missing piece is any hint about domain (real vs. complex) or how it differs from calculator_magnitude.

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% for the single 'value' parameter, and the description's examples echo the schema's own examples array rather than adding new meaning. Per the high-coverage baseline, a 3 is appropriate; no format, range, or type guidance is contributed beyond 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?

The description states a specific verb ('calculate') and resource (absolute value, written as |x|), backed by concrete examples that make the operation unambiguous. It does not distinguish itself from the nearby sibling calculator_magnitude, which for real numbers computes essentially the same thing.

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 this to calculate |x|' implies the usage context but gives no explicit when/when-not guidance. With ~140 calculator siblings including calculator_magnitude, a one-clause disambiguation note would have been valuable; nothing here routes the agent away from near-duplicates.

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