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

Annotations already establish readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuinely new behavioral context: the result exposes splits, merges, changed meanings and unmapped codes, and that one-to-one equivalence must not be assumed. That cardinality warning is exactly the kind of nuance annotations cannot express.

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 tight sentences, front-loaded with the core action and closed with the single most important caveat. Every clause earns its place.

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 values need not be explained, and the operation semantics are conveyed. However, with three fully required, undocumented parameters, an agent still lacks the guidance needed to populate the source/target classification IDs and the code list correctly, leaving a real gap for a tool of this complexity.

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 0% and the three parameters carry only bare titles ('Codes', 'Source Classification Id', 'Target Classification Id'), all required. The description never explains that codes is a list of source codes, nor that the two IDs select the source and target classification versions, so it fails to compensate for the schema gap.

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 uses a specific verb (map) on a specific resource (codes between two classification versions) and clarifies the mechanism: 'Apply official stored correspondences.' It conveys the operation clearly, though it never names a sibling (e.g. validate_codes or search_codes) to sharpen differentiation.

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 warning 'Never assume one-to-one equivalence' hints at expected behavior but gives no when-to-use, when-not-to-use, or alternative tool guidance. With nine sibling tools, the agent must infer from the name alone that this is the cross-version mapping tool rather than validate_codes or get_code_definition.

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