action

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the action (run a command) but doesn't disclose side effects, whether the command may be destructive, require specific REAPER state, or return any output. For a tool that can execute arbitrary REAPER commands, this is a significant 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, focused sentence that front-loads the action and resource. Every word earns its place, and it avoids unnecessary elaboration.

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 tool that executes arbitrary REAPER commands, the description is thin. It lacks information about return values, error handling, side effects, and prerequisites. The output schema is absent, and the description doesn't explain what happens after the command runs. An agent would need external knowledge to use this tool safely and effectively.

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 0%, so the description must compensate. It explains that command_id is a numeric command id, which adds meaning beyond the bare integer type. However, it doesn't provide details like valid ranges, how to find command IDs, or whether the command ID is a native REAPER ID or a custom one. The description adds some value but leaves gaps.

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 states a specific verb ('Run') and resource ('REAPER Main_OnCommand by numeric command id'), which clearly identifies the tool's function. It distinguishes itself from siblings like run_lua and reaper_call by specifying the exact REAPER API function and input type, though it doesn't explicitly name alternatives.

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: use this tool when you need to invoke a REAPER command by its numeric ID. It doesn't explicitly state when not to use it or mention alternatives like run_lua for scripts, but the context of sibling tools and the specific API reference provide some guidance.

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