generate_image

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions that the tool generates images via OpenRouter with a specific model, which adds useful context about the external service and generation method. However, it lacks details on potential limitations (e.g., rate limits, costs, output format, or error handling), which are important for a tool that likely involves API calls and resource consumption.

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 concise sentences that are front-loaded with the core purpose and usage rule. Every word earns its place by clarifying the tool's intent and distinguishing it from siblings, with no redundant or vague phrasing. It efficiently communicates essential information without unnecessary elaboration.

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 the tool's complexity (image generation via external API) and lack of annotations or output schema, the description is somewhat incomplete. It covers the purpose and usage well but misses behavioral details like expected output format, error conditions, or dependencies (e.g., token configuration via 'configure_openrouter_token'). For a tool with no structured safety or output info, more context would be beneficial.

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%, with clear descriptions for both parameters (e.g., 'prompt' is for 'describing the NEW image to create from scratch'). The description reinforces the 'NEW' aspect for the prompt but doesn't add significant semantic details beyond what the schema already provides, such as explaining prompt best practices or aspect ratio implications. Baseline 3 is appropriate given the high schema coverage.

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 specific action ('Generate a NEW image'), the resource ('image'), and the method ('from text prompt using OpenRouter (Gemini 2.5 Flash Image)'). It explicitly distinguishes this tool from modification tools like 'edit_image' among its siblings by emphasizing 'creating a completely new image, not when modifying an existing one.'

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 provides explicit guidance on when to use this tool ('ONLY when creating a completely new image') and when not to use it ('not when modifying an existing one'), which clearly differentiates it from alternatives like 'edit_image' among the sibling tools. This direct exclusion rule offers strong usage context.

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