stop_timeline

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

No annotations are provided, so the description carries the full burden. 'Stop playback' is transparent about the core action, but it does not disclose side effects such as playhead behavior, error conditions, or state changes. For a simple stop command, this is adequate but not rich.

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, direct sentence with no waste. It is front-loaded and immediately conveys the action.

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 zero-parameter control tool with no output schema, the description is nearly complete. It states what the tool does, but could add context about assumed state (e.g., timeline must be playing) or post-condition (e.g., playhead remains). This minor gap prevents a perfect score.

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, so there are no parameter semantics to clarify. Per baseline rules, a score of 4 is appropriate since the description is not required to explain parameters that don't 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 'Stop playback in the current timeline' uses a specific verb and resource, clearly stating the action and scope. It differentiates from sibling tools like play_timeline and set_playhead_position.

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 (stop the current timeline's playback) but provides no explicit when-to-use guidance or alternatives. The phrase 'current timeline' gives context, but there is no mention of conditions like whether the timeline is playing or if any action is taken when already stopped.

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