Sketch to Design

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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false), lowering the bar. The description adds genuine behavioral context beyond them: 'Result files are saved to disk and their paths returned,' which compensates for the missing output schema. It still omits credit cost and processing-time behavior, so not a 5.

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 definition is front-loaded with the core purpose before the 'Best for' clause and the input-quality caveat, and every sentence earns its place. It is appropriately sized for a 10-parameter tool, though the trailing quality note is slightly less essential than the rest.

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 10-parameter mutation tool with no output schema, the description covers purpose, ideal inputs, and the file-save/return behavior that the missing output schema would otherwise leave ambiguous. It does not mention credit estimation or the review_settings flow, but those are documented in the schema, so nothing critical is missing.

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%, so the schema already documents all 10 parameters, including the rich style enum guidance ('never choose for the user', 'Call describe_tool'). The description only echoes 'optionally in a named style' and adds no syntax or format detail beyond the schema, so the baseline 3 applies.

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: 'colour a line sketch into a finished design, optionally in a named style.' The 'Best for' clause names the input domain (sketch, line art, wireframe), which effectively separates it from the many sibling design tools such as td_style_transfer and td_design_generation that operate on arbitrary images.

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?

'Best for: turning a sketch, line art or wireframe into a full-colour, detailed design' gives clear when-to-use context, and 'Clear, simple sketches with well-defined lines work best' adds a quality precondition. However, it names no alternative tool and states no exclusions, so an agent is not explicitly routed away from siblings.

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