thincms_generate_media_variants

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

With no annotations provided, the description carries the full burden. It discloses that the tool only creates variants for images without them, and lists the three sizes. It also notes the admin-only restriction. However, it does not mention whether the operation is reversible, if it is synchronous or asynchronous, or any performance implications. The behavioral details are adequate but not comprehensive.

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 extremely concise: three sentences, each adding distinct value (purpose, sizes, restrictions). Front-loaded with the key verb and resource. No extraneous or redundant information.

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 presence of two well-documented parameters and the absence of output schema or annotations, the description provides sufficient context for an agent to understand when and how to call it. It could be improved by noting what the tool returns (e.g., summary of generated variants) or any limitations (e.g., only processes images, not other media types). Nevertheless, it is largely complete for a straightforward batch operation.

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 description does not mention any parameters. However, the input schema has 100% coverage, so both parameters (siteId and confirmProductionWrite) are already documented in the schema. The description adds no extra semantic meaning beyond what the schema provides, resulting in a baseline score of 3.

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 clearly states the tool's purpose: generating WebP image variants (thumbnail, medium, large) for all images in the media library that lack them. It explicitly names the action ('Generate') and the resource ('media variants'), and distinguishes itself from sibling media tools like upload, update, or delete.

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 usage for batch generation of missing WebP variants and flags 'Admin-only' as a restriction. However, it does not explicitly state when to use this tool versus alternatives (e.g., uploading already-optimized images, or manually generating variants via update_media). No guidance on prerequisites or consequences.

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