List widget areas

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

Annotations already establish readOnlyHint and non-destructive status, but the description adds valuable behavior beyond them: it warns that block themes typically have no classic sidebars and that this is expected rather than an error. It also clarifies that the response includes both widget areas and their placed widgets.

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 with no filler. The main action and target are front-loaded, and the second sentence adds genuinely useful edge-case context about block themes without bloating the description.

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 listing tool with one optional documented parameter and a safety profile already covered by annotations, the description is complete. It states what is returned, handles the block-theme empty-result case, and needs no output schema or further elaboration.

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?

The single optional site_id parameter is fully documented in the schema with 100% coverage, including behavior for single-site vs multi-site setups and a pointer to list_sites. The description adds no parameter-specific detail, but the schema already carries that burden.

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 uses a specific verb ('List') and names the resource ('the theme's widget areas (sidebars)') plus the content returned ('widgets currently placed in each'). This clearly distinguishes the tool from list_widgets and other theme-related tools without ambiguity.

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 description implies its use by stating what it lists, and the block-theme note gives helpful context about expected empty results. However, it does not explicitly mention when to prefer this over sibling tools like list_widgets, nor does it state exclusions or alternatives.

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