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

Annotations (readOnlyHint=false, openWorldHint=true) already signal this is a cost-bearing generative tool. The description adds the per-image pricing, which is useful operational context beyond the annotations, and clarifies the create-vs-edit behavior. But it doesn't disclose how the presence/absence of the image parameter changes behavior, default aspect ratio handling, or output characteristics.

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?

A single sentence that front-loads the core purpose (create or edit) and tucks cost at the end. Every element earns its place with no redundancy or filler.

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 generative tool with no output schema, the description covers the two key modes but omits the image↔prompt conditional behavior and any return-format guidance. With a large set of closely overlapping siblings, more context on how this image tool differs from ai_image_generator would improve completeness.

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 67%, so the schema documents prompt and image, with aspect_ratio fully enumerated. The description adds modest semantics by clarifying that prompt means either 'what to create' or 'how to edit', which maps directly to the prompt parameter. It does not explain the conditional relationship (image present → edit, absent → create), which would meaningfully enrich parameter understanding.

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 verb+resource ('generate' an image) and distinguishes two operating modes: creation from a text prompt and editing with an input image. However, it does not differentiate from the sibling 'ai_image_generator' or 'ai_image_editor', which likely share nearly identical purpose, so an agent cannot tell them apart from the description alone.

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?

No guidance on when to use this tool versus the many overlapping siblings (ai_image_generator, ai_image_editor, ai_image_expander). No exclusions, prerequisites, or decision criteria are provided. The only extra signal is the $0.10-per-image cost note, which is operational, not usage guidance.

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