generate_image

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

With no annotations provided, the description carries the full behavioral disclosure burden. It does well by revealing the anonymous free tier, the 1K watermarked output, and the 40-120 second latency. It could additionally mention rate limits or retention behavior, but the disclosed constraints materially affect invocation expectations.

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?

Three concise sentences, each carrying distinct information: function and output, access constraints, and output/latency expectations. The most important functional statement is front-loaded, with no filler or repetition.

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 relatively simple three-parameter tool, the description covers the essential operational context: what it returns, authentication requirements, output properties, and latency. It does not mention error scenarios or whether the hosted URL is temporary, but the presence of a timeoutSecs parameter and the sibling free_tier_limits tool suggest those gaps are minor.

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 only 33% (only prompt is described). The description adds little beyond 'text prompt' for parameter meaning, though the prompt schema itself gives useful prompt-craft guidance. aspectRatio is self-explanatory via its enum, and timeoutSecs has default/min/max in the schema, so the description need not repeat them but also does not compensate for the low 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 uses a specific verb and resource: 'Generate an image from a text prompt and return a hosted image URL.' It clearly states the tool's function and output format, and its scope is unambiguous even against the sibling tool names (list_models, browse_tools, free_tier_limits).

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 gives clear context for when to use the tool: when an image needs to be generated from a prompt, with no API key or account needed because it runs on the anonymous free tier. It does not explicitly name alternatives or exclusion criteria, but the context is sufficient for a simple generation task.

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