generate_image

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

With no annotations, the description carries the full burden and does well: it discloses a hidden trademark filter that rewrites brand terms before the prompt leaves the machine, points at the terms_removed field to audit that rewrite, and warns that the returned path is local-only so an unuploaded file leaves NewsArticle.image unreachable by crawlers. It omits cost, latency (image generation is typically slow/paid), and any auth requirements.

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 short paragraphs, front-loaded with the action, then the prompt-authoring rule, then the output-handling caveat. Every sentence carries a distinct instruction; no 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?

For a 3-param tool with no annotations, no output schema, and 0% schema coverage, the description does cover the highest-risk behaviors (prompt content, filter side effect, local-path gotcha). But two of three parameters remain opaque and nothing is said about cost, timeout, or failure modes, so an agent still has to guess on invocation details.

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 0%, so the description must compensate. It gives real semantic guidance for 'prompt' (build from visual concepts, not brand names), but 'slug' and 'style' go entirely unexplained in both places, including which of banner/square to pick and what slug controls. Partial compensation only.

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?

States a specific verb and resource ('Generate a banner image for the article') plus the side effect ('save it locally'), and the 'Step 8' framing places it unambiguously in the workflow. No sibling tool could be mistaken for it.

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 step numbering situates it in the pipeline, and the description explicitly routes the agent forward: 'Upload the file and pass a public https URL to build_schema.' It stops short of stating when not to use it or what alternative exists if image generation is undesired.

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