preview_diagram

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

The description discloses the side effect of opening an HTML preview in the browser, consistent with openWorldHint=true annotation. It does not cover permissions, rate limits, or behavior with multiple diagrams, but annotations already cover the non-destructive and open world hints.

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 sentences cover the main action and a key usage tip with no wasted words. Front-loaded with the core purpose.

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 adequately explains the input parameters and the action. It could benefit from mentioning that the preview opens in the browser and that return value is minimal, but it is complete enough for a preview 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?

The description adds meaningful guidance beyond the schema, such as explaining the color naming convention (trailing lowercase for colors, capitalizing for literal text) and providing an example. This enriches the parameter semantics beyond the schema's 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 clearly states the verb (render and open HTML preview), resource (DGMO diagrams), and distinguishes from siblings by mentioning DGMO syntax and referencing get_language_reference for syntax help.

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 explicitly directs users to call get_language_reference for DGMO syntax help, providing a clear when-not-to-use. However, it does not differentiate from sibling tools like render_diagram or open_in_app, so guidance is slightly limited.

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