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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile needs no restating. The description adds useful behavioral content by specifying exactly which character layers are returned and that site notes are included; with an output schema present, further return-value detail is unnecessary.

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 with zero filler; the return content is front-loaded and the supported layout families follow as supporting detail. Nothing needs trimming or reordering.

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 a read-only single-parameter lookup with rich annotations and an output schema, the description is essentially complete: it states the return layers, the notes field, and the supported layouts. Only the omitted-parameter default and the relationship to compare_layouts are left to the schema and inference.

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 the single optional 'layout' parameter is fully documented in the schema, including example names and the omitted-default behavior (US QWERTY). The description's layout examples duplicate what the schema already lists, adding no new syntax or default guidance.

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 gives a specific verb and resource ("Returns the key map of a keyboard layout") and enumerates the payload contents (plain, Shift, AltGr characters plus the site's notes), so an agent knows exactly what it gets. It does not name or contrast itself with the sibling compare_layouts, so it falls short of full sibling 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?

There is no explicit when-to-use or when-not-to-use guidance, and no alternative tool is named, even though compare_layouts and get_keycode are close candidates. Usage is only implied by the verb 'Returns' — a single-layout lookup.

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