presentation-get-layout-device

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

readOnlyHint=true already covers the safety profile, so the bar is lower; the description adds genuine behavior beyond annotations by documenting the default-device fallback when name is omitted and the headless-site single-device case. It stops short of describing the returned device structure or any permission requirements.

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 core lookup behavior front-loaded and the situational caveat second. No filler or redundancy.

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 simple read-only getter with a fully documented schema and readOnlyHint, the description covers the essentials, including the non-obvious default behavior. There is no output schema and the description doesn't hint at the returned shape, which is a minor remaining gap.

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 all three parameters are documented in the schema (name, full, fields), including the warning that 'full' is diagnostics-only and very large. The description only restates the name-omitted default, so it adds nothing beyond the schema; baseline 3 applies.

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 and resource ('Gets a layout device') plus the key default-fallback behavior when name is omitted, which is a precise scoping statement. It doesn't explicitly contrast with the closely named sibling presentation-get-layout, but the resource is distinct enough that an agent can differentiate.

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 headless-site note ('there is usually only the Default device') gives useful context for interpreting results, implying the tool's typical use. However, it never states when to prefer this over presentation-get-layout or presentation-list-renderings, so usage is only implied rather than guided.

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