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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds meaningful behavioral context beyond annotations: exact conversion constants, the NIST source, and that each unit's definition and source are returned.

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?

The description is front-loaded and dense with useful information: conversion scope, exact constants, return behavior, and the optional "to" semantics. Despite the long unit list, every element supports correct tool selection or invocation.

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?

There is no output schema, but the description states that results include the definition and source of each unit. Combined with full schema coverage and safety annotations, this is nearly complete for a read-only conversion utility, though it does not discuss precision or invalid-unit handling.

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%, so the schema already documents the units, aliases, and value constraints. The description adds meaning beyond the schema by explaining the omitted "to" behavior, which is not captured in the parameter 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 and resource: converting a gold weight between an extensive list of named units. It is clearly distinguishable from sibling tools such as get_gold_price_per_gram and calculate_jewelry_value because it is purely a unit conversion utility.

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?

The description gives clear operational context, including that omitting "to" returns every unit. It does not explicitly exclude related price or jewelry-value tasks, but the conversion scope is unmistakable given the sibling tools.

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