play

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

With no annotations provided, the description carries full burden for behavioral disclosure. 'Start playback' implies a state-changing action but doesn't describe what happens (e.g., begins playback from current position, affects transport state), what permissions are needed, whether it's reversible, or what happens if playback is already active. It provides minimal behavioral context beyond the basic 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 ('Start playback') - just two words that directly convey the core action. There's zero wasted language, and it's perfectly front-loaded with the essential information.

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 this is a simple action tool with zero parameters and an output schema exists, the description is minimally adequate. However, for a state-changing transport control in an audio/DAW context (inferred from sibling tools), it should ideally mention more about behavior, prerequisites, or relationship to other transport controls. The existence of an output schema means return values are documented elsewhere.

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 (schema coverage 100%), so there are no parameters to document. The description appropriately doesn't discuss parameters, which is correct for a parameterless tool. Baseline is 4 when no parameters exist.

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 'Start playback' clearly states the action (start) and target (playback), but it's somewhat vague about what exactly 'playback' refers to in this audio/DAW context. It doesn't distinguish this tool from sibling tools like 'record' or 'stop' beyond the basic verb difference.

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 provides no guidance about when to use this tool versus alternatives like 'record', 'stop', or 'goto_position'. There's no mention of prerequisites (e.g., requires a session to be loaded), context (e.g., playback from current position), or exclusions (e.g., cannot use while recording).

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