cocos_list_builtin_themes

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

No annotations are provided, so the description carries full burden. It discloses that the tool returns themes 'verbatim' (exact format) and mentions they are 'bundled' (pre-installed). However, it doesn't describe the return structure (e.g., list format, JSON), error conditions, or performance characteristics. The description adds some behavioral context but leaves gaps for a tool with no annotation coverage.

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 perfectly sized with two sentences. The first sentence states the core purpose, and the second provides practical usage guidance. Every word earns its place with zero waste or redundancy.

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 parameterless tool with no output schema, the description provides good context about what's returned ('five bundled UI themes verbatim') and clear use cases. However, without annotations or output schema, it could benefit from more detail about the return format (e.g., array of theme objects) to be fully complete. The description does well given the tool's simplicity.

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 tool has 0 parameters with 100% schema description coverage. The description appropriately doesn't discuss parameters since none exist. It focuses instead on what the tool returns and its use cases, which is the right approach for a parameterless tool.

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 specific action ('Return all five bundled UI themes verbatim'), identifies the resource ('bundled UI themes'), and distinguishes from siblings by focusing on listing built-in themes rather than creating or modifying UI elements like most sibling tools. It provides exact scope ('five') and output format ('verbatim').

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 provides two concrete use cases: 'previewing the palette before pinning one' and 'as a starting point for a custom= override passed to cocos_set_ui_theme'. It names the specific alternative tool (cocos_set_ui_theme) for when customization is needed, giving clear guidance on when to use this tool versus alternatives.

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