generate_image

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

With no annotations, the description bears full burden. It discloses the cost and that the output is a PNG image. The prompt length limit is inherited from the schema. It does not mention error handling or idempotency, but for a generative tool this is reasonable.

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 concise sentences: first states purpose, second adds cost and aspect ratios. No extraneous information. Front-loaded with the core action.

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 no output schema, the description does not explain the return format (e.g., URL or base64). It covers key usage constraints (cost, aspect ratios) and input limits. Missing response details, but acceptable for a simple generation tool.

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 100%. The description repeats the aspect ratio enum and the prompt length, adding no new semantic information beyond the schema fields. Baseline 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?

The description clearly states 'Generate a PNG image from a text prompt,' which specifies the verb, resource, and input. It is distinct from sibling tools (no other image generation tools). Includes additional details like cost and aspect ratios.

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 mentions a cost of $0.03 USDC via x402, which is a key usage constraint. It also lists available aspect ratios. However, it does not explicitly state when not to use or mention alternatives, but no alternatives exist in the sibling list.

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