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

The description's strongest contribution beyond annotations is the safety framing: this is a dry run that changes nothing and the agent must report findings to the person and wait for approval before calling update_theme. That meaningfully supplements readOnlyHint and destructiveHint=true. However, the annotations pair readOnlyHint=true with destructiveHint=true, and the description never reconciles this or explains why a no-change plan carries a destructive hint, leaving an agent uncertain about side effects.

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?

One long run-on sentence with elided verbs and no sentence boundaries, which makes the enumeration of plan outputs hard to parse. The core purpose and the ordering constraint are front-loaded, so nothing is buried, but the fragmentary style costs readability rather than saving space.

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 no output schema, the description carries the burden of describing what comes back, and it does so well by listing the five categories of plan content. The missing piece is the meaning of the 'theme' parameter and any note on what happens when the theme is already current.

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 50%: 'site' is documented in the schema and the description reinforces it as the single target site. 'theme' is left bare in the schema and the description never clarifies its role — presumably the site's current theme or the bundled theme version being compared — so the highest-risk ambiguity goes unaddressed.

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 names a specific operation: a non-mutating comparison of the bundled theme's newer release against the site's own edits, and it enumerates what the plan contains (release notes, files the release changes, files the site changed, files both touched, merge stop points). This clearly distinguishes it from update_theme and resolve_theme_update, though the telegraphic, article-dropping phrasing ('On one site of the account, named in site. Before update_theme, and changing nothing:') forces the reader to reconstruct the sentence.

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?

It states an explicit ordering rule — run this 'before update_theme' — and an explicit behavioral constraint, that it changes nothing. It does not address resolve_theme_update, the natural sibling once the plan surfaces conflicts, nor does it say when planning can be skipped, so the alternative routing is incomplete.

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