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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the mutation profile is covered. The description adds useful context about legacy aliases and that custom color parameters override the preset, but it never explains the scope of the destructive behavior, such as whether existing custom CSS, fonts, or prior overrides are wiped, nor what permissions are needed.

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?

Four short sentences with the core action front-loaded and no filler. The alternative-tool note and alias note are each one line, though the preset list in the first and second sentences is slightly redundant with the schema enum.

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?

With six optional parameters, full schema coverage, and no output schema, the description supplies the key preset naming, alias, and override context an agent needs. The remaining gap is behavioral: with destructiveHint=true it should say what existing customization is replaced or lost when a theme is applied.

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 coverage is 100%, so every parameter, including the button_style enum and hex color formats, is already documented in the schema. The description adds only the general notion that custom colors act as overrides, which repeats the per-parameter 'Overrides theme' notes rather than adding new semantics.

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 ('Apply a visual theme preset') and names the preset source package, so the effect is concrete. It also explicitly contrasts itself with the sibling tool apply_theme and mentions the related list_themes-style preset names, letting an agent distinguish it without opening a schema.

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?

Gives clear routing guidance ('Prefer apply_theme for the same behavior') and notes that legacy names like clean/cream/dark are accepted aliases. It does not explain why two equivalent tools exist or when set_theme would be the better choice, so the alternative is named but the exclusion criteria are incomplete.

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