gemini_generate_image

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

With no annotations provided, the description must carry the full burden of disclosing side effects and behaviors. It fails to mention that the tool saves images to disk (defaulting to ~/Documents/nanobanana_generated/), any network/API usage, authentication requirements, or return values. It only mentions session-based consistency, which is a feature but not a behavioral 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?

The description is two short sentences that front-load the core purpose. Every word adds value, and there is 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?

Despite a 7-parameter schema and no output schema, the description does not explain the tool's overall behavior (e.g., where the generated image goes, what the tool returns, or how the session mechanism operates). The session consistency mention is a start, but the description is too sparse for the complexity involved.

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 all seven parameters are already documented in the schema. The description adds no new parameter-level semantics beyond what the schema provides, making the baseline 3 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?

The description clearly states the tool generates images via Gemini, and mentions a key differentiator (session-based image consistency) that distinguishes it from siblings like gemini_chat or gemini_edit_image. The verb and resource are specific and unambiguous.

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 the tool is for generating new images and optionally using session consistency, but it does not explicitly address when to use this tool versus alternatives like gemini_edit_image or gemini_chat. No exclusion criteria or alternative recommendations are given, so usage guidance is only implied.

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