create_poster_variants

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

With no annotations provided, the description carries the behavioral disclosure burden. It accurately communicates the key batch behavior (several variants in one call) and the comparison intent, but it does not mention return format, failure modes, or any side effects. This is adequate but not rich.

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 concise sentence that delivers the core value proposition without wasted words. It is front-loaded with the batch concept and ends with the purpose, making it easy to scan. Slightly more explicit structure would improve it, but it is appropriately sized.

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 3-parameter tool with nested objects and no output schema, the description gives enough context to select the tool and understand its general purpose. However, an agent would still need to rely on the schema for override semantics and would not know what the response contains. Functional for selection, incomplete for full invocation confidence.

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 100%, so the structured schema already documents content, template fallback behavior, and variant overrides. The description adds the conceptual 'same message across templates' framing but no additional parameter-level detail beyond what the schema provides.

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 conveys that the tool generates the same message across multiple templates/palettes in a single call, which differentiates it from the singular create_poster sibling. It lacks an explicit verb but the resource and batch scope are unmistakable.

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 phrase 'to compare directions' provides a clear context for when this tool is appropriate: when the user wants to explore multiple visual directions at once. It does not explicitly name alternatives or exclusions, but the batch comparison purpose is evident from the description alone.

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