mame_get_regs

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

With no annotations, the description carries the full burden. The verb 'Read' explicitly indicates a non-destructive operation, which is useful. However, it does not disclose details about device selection, return format, or any potential side effects, though for a simple read operation this is a minor gap.

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 a single sentence that lists the exact registers read, with no filler or unnecessary words. It is well-structured and immediately communicates the core functionality.

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?

The tool has only one parameter and no output schema. The description provides the essential purpose and register list, which is adequate for basic use. However, it lacks explanation of the 'device' parameter and return format, leaving some ambiguity for an agent that needs to invoke it correctly.

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 input schema has one parameter 'device' with a default, but no description is provided. The tool description does not mention the 'device' parameter at all, leaving the agent to infer its meaning from the name alone. Since schema coverage is 0%, the description should compensate, and it fails to do so.

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 tool's function: 'Read all CPU state registers' with explicit register names (D0-D7,A0-A7,PC,SR,USP). It distinctively identifies the resource (CPU state) and is easily distinguished from sibling tools like mame_set_reg (write) and mame_read_memory (memory read).

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 implies usage for inspecting CPU register state, but it does not explicitly state when to use this tool versus alternatives like mame_set_reg or mame_read_memory. No exclusions or alternative references are provided, leaving the context implied rather than explicit.

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