Generate Image

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

No annotations provided, so description carries full burden. It discloses return values (saved file path, model, tokens, cost), removeBackground behavior (first-use model download, fallbacks, mode effects), and runtime validation. Missing auth/rate limits, but still transparent for a complex tool.

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?

Description is relatively long but well-structured: starts with core purpose, then specific capabilities (removeBackground), then parameter details. Each sentence adds value. Slightly verbose in removeBackground section, but overall efficient.

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 12 parameters, nested object, no output schema, and 100% schema coverage, the description is thorough. It explains return values and parameter interactions (e.g., seed reproducibility, session continuation, model support). Could add error handling details, but still highly complete.

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%, baseline 3. Description adds significant value: explains sessionId for multi-turn edits, removeBackground sub-parameters (auto, chroma, threshold) with defaults and dependencies, and default resolution/aspect-ratio derivation. This goes well beyond the schema.

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?

Description clearly states tool generates or edits images using Google Gemini, listing two main modes: text-to-image and editing with reference images. The sibling tool process_image is not differentiated explicitly, but the description's focus on generation/editing implies separation.

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?

Provides clear guidance: 'Provide just a prompt for text-to-image generation. Add image file paths to edit or use reference images.' Also gives detailed usage instructions for removeBackground modes (auto, chroma, threshold) with pros and cons. Lacks explicit exclusions or when-not-to-use, but context is sufficient.

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