netease_set_playback

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

Annotations already communicate mutation, idempotency, and openness, but the description adds valuable behavioral detail: it verifies UI state, does not blindly toggle, and refuses when the UI state is unknown. This is meaningful context beyond the structured annotations and helps the agent predict failure behavior.

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 compact and front-loaded. The first sentence states the core purpose, and the next two add important caveats without redundancy. Every sentence earns its place.

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 simple one-parameter tool with an output schema and meaningful annotations, the description is nearly complete. It covers the intended action, the refusal behavior, and the verification aspect. It could be slightly stronger by explicitly pointing to netease_get_status for checking unknown UI state before calling this tool, but the need is reasonably implied.

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 mentions 'play or pause,' which maps directly to the action enum, and 'does not blindly toggle' clarifies that the action values are absolute target states. However, it does not explicitly name the action parameter or explain its requiredness, leaving much to the schema.

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 function: explicitly play or pause and verify the UI state. It is specific about the verb and resource, but it does not explicitly distinguish itself from sibling tools like netease_play_result or netease_get_status, so it falls short of full sibling differentiation.

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 clear context: use this tool when you need an explicit play or pause, not a blind toggle. It also implies a prerequisite—unknown UI state is refused—so the agent should confirm state first. However, it does not explicitly name an alternative or say 'use netease_get_status first'.

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