List ROMs

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

With no annotations, the description carries the full burden. It discloses the data source (--roms-dir) and implies a non-destructive read operation via 'Lists'. However, it does not explicitly state there are no side effects or that it is read-only, though this is strongly implied. Adequate but minimal.

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 two short sentences with no wasted words. The first sentence front-loads the action and source, and the second provides a direct usage pointer. Highly concise and well-structured.

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 simple tool with no parameters and no output schema, the description covers all essential info: what it lists, where from, and how to use the result. It could explicitly mention the output format (e.g., list of objects with a 'name' field), but this is implied by 'Use the returned "name"'. Sufficiently complete.

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 zero parameters, so the schema is empty and the baseline is 4. The description adds semantic context by explaining that the returned 'name' feeds into load_rom, which clarifies the purpose of the tool's output and indirectly helps with the sibling's parameter.

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 action ('Lists') and the resource ('ROM files') with a specific source ('--roms-dir'). It also distinguishes the tool from siblings by linking its output to load_rom, making its role unambiguous.

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 second sentence provides explicit usage context: the returned 'name' should be used with load_rom. This indicates when to use the tool (before loading a ROM). There are no alternatives to exclude, so this is clear and sufficient.

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