stop

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

With no annotations provided, the description carries the full burden of disclosing behavior. It explicitly states that stopped playback cannot be resumed, which is a critical behavioral trait. However, it does not mention other effects such as clearing the queue or whether group players are affected. For a simple stop operation, the disclosed trait is significant, so a score of 4 is appropriate.

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 sentences long, front-loads the core action, and adds a concise, important caveat. Every word earns its place; there is no redundancy or unnecessary detail.

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?

Despite the tool's simplicity, the description fails to explain what the 'player' parameter expects (e.g., an ID from list_players, a name, a URL). The output schema exists, so return format is not needed, but the input parameter is entirely unexplained. An agent cannot correctly call this tool without external knowledge, making the description incomplete for a tool with a required parameter.

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 schema has a single required parameter 'player' with 0% description coverage, and the description provides no explanation of what 'player' refers to, its format, or how to obtain a valid value. Since the schema provides no help, the description must compensate, but it does not. This is a major gap for a tool with only one 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 tool's action: 'Stop playback on a player.' It uses a specific verb and resource, and the caveat about non-resumability differentiates it from pause (which is resumable) and other playback controls. This is sufficient for an agent to distinguish it from siblings.

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 gives a behavioral caveat ('can't be resumed with play() - start something new instead') but does not explicitly tell the agent when to use this vs. pause or other alternatives. It implies that stop is final, but it does not name pause as the resumable alternative. This is clear context but lacks explicit exclusions or alternative guidance.

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