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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description adds useful overwrite semantics: omitted formatLayouts preserves independent formats, an empty map resets them, and main layouts do not overwrite independent phone-format layouts.

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 three tight sentences with no waste. The primary replace behavior is front-loaded, followed by the key formatLayouts and layout interaction caveats.

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?

Given the complex nested schema, destructive annotation, and presence of an output schema, the description covers the essential replace semantics and key edge cases. It could be more complete by naming sibling alternatives or permission requirements, but the core behavioral context is present.

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 75%, so the schema already documents most parameters and nested objects. The description adds some meaning around formatLayouts behavior and layout interaction, but most parameter details remain delegated to 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 and resource: it replaces complete saved screenshot layouts for specified device sizes and language. The scope is clear, but it does not explicitly distinguish this tool from related siblings such as sync_layout, transform_layout, or get_layout.

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?

Usage is implied by the replace/save semantics, and the description gives important edge-case behavior for formatLayouts. However, it does not explicitly say when to use this tool versus get_layout, sync_layout, transform_layout, or translate_layouts.

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