Transport control

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

No annotations are provided, so the description must disclose behavioral traits. It does mention that the tool returns the resulting play state as bit flags, which is a concrete behavior. However, it does not clarify potential side effects, such as whether starting playback could interrupt recording or if there are any constraints (e.g., can't record without an armed track). There is no description of error behavior or prerequisites, leaving the agent in the dark beyond the immediate action.

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 extremely concise: two sentences pack purpose, actions, and return semantics. It is front-loaded with the main purpose and includes the necessary detail about the return format. There is no wasted text, achieving high efficiency.

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 the tool's simplicity (single parameter with enum) and lack of output schema, the description is mostly complete. It covers the actions and the return value, sufficient for basic invocation. However, it lacks behavioral context such as prerequisites (e.g., must have an open project) or potential side effects (e.g., changes to project state), which could be important for an agent. Thus, it is adequate but not thorough.

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?

With 0% schema description coverage, the description must explain the parameter meanings. It does list the possible values (play, stop, pause, record) and explains the return state values, which adds context to the 'action' parameter. However, it does not elaborate on the exact effect of each action (e.g., does 'pause' toggle or set?), but since the enum is self-explanatory and the return state clarifies outcomes, a baseline of 3 is appropriate.

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 purpose: controlling playback (play, stop, pause, record) and returning the resulting state. It is specific with the verb 'control' and the resource 'playback', and it distinguishes itself from sibling tools like reaper_set_tempo or reaper_transport, which have different functions. The actions are enumerated, making the purpose 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 description implies when to use this tool: when the agent needs to control playback or recording. However, it does not explicitly state when not to use it or mention alternatives for similar functions. For instance, there is no direct sibling for transport control, so guidance is minimal but not misleading. A score of 3 reflects that usage is clear but not fully elaborated.

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