asset_generate_hero

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

The description adds significant behavioral detail beyond the minimal annotation (openWorldHint: true): it discloses two operation modes, unsupported inline_svg, accepted aspect ratios, brand bundle injection, and variant return behavior. This informs the agent effectively.

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 three terse sentences: first states purpose, second details modes and unsupported, third lists options and return behavior. Every sentence adds value, with no waste, and the key information is front-loaded.

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?

It covers the main purpose, modes, key parameters, and return behavior. The missing details (description of brief and output_dir) are minor since brief is the required input and output_dir is a standard file path. No output schema exists, but the description implies return of variants. Slightly incomplete but acceptable.

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?

The description adds meaning to four of six parameters (mode, aspect_ratio, brand_bundle, count) by listing allowed values and behavior. The remaining parameters (brief, output_dir) are not described but their purpose is inferable from context (brief is the prompt, output_dir for output). This compensates well given no schema descriptions.

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 explicitly states it generates 'marketing-hero / landing-page banner art', which is a specific verb-resource pair. This clearly distinguishes it from sibling tools like asset_generate_logo or asset_generate_app_icon.

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?

It mentions two modes and unsupported inline_svg, providing some guidance on when to use each mode. However, it does not explicitly state when not to use this tool compared to alternatives (e.g., for logos or icons), nor does it provide exclusion criteria.

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