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

With no annotations, the description conveys the key asynchronous behavior: it returns a jobId rather than the image and tells the agent to poll ryla_generation_status. It does not cover credit costs or content-safety side effects, but the async pattern is a meaningful disclosure.

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 action and input dimensions are front-loaded and the async follow-up is stated efficiently. Every part earns its place.

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 generation tool with no output schema, the description covers the response protocol via jobId and the polling instruction, while the schema covers the inputs. Missing sibling-selection guidance and cost/safety warnings are the main gaps, but the tool remains invocable.

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?

All four parameters are already described in the schema, so the description adds no detailed parameter semantics beyond summarizing vibe/niche/promptInput. The schema carries the burden, so the baseline of 3 is appropriate.

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 clear action — generate base character images — and the input dimensions (niche/vibe/prompt). The mention of jobId distinguishes it from direct-return generation tools, but it does not name a sibling like ryla_generate_character_sheet, so differentiation is implicit rather than explicit.

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 text implies usage for base character generation and provides a follow-up polling step. It does not state when to choose this tool over siblings such as ryla_generate_image or ryla_generate_character_sheet, nor does it give exclusions, leaving selection to inference from the name.

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