repeat

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

No annotations are provided, so the description carries the full behavioral burden, and it discloses almost nothing: it does not say whether the mode persists, whether it targets the active device by default, or what happens if device_id is omitted. 'Needs state' is the only behavioral hint and it merely echoes the schema.

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?

Two short fragments, front-loaded with the action. 'Needs state' is largely redundant with the schema's required array, so it is not perfectly economical, but nothing is bloated.

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?

This is a simple two-parameter tool with full schema coverage and no output schema, so the schema does most of the work. The description is adequate but leaves device-targeting and persistence behavior unstated, which for a stateful playback control would be useful.

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 coverage is 100% and the enum values (off/track/context) are already fully explained in the schema, so the baseline of 3 applies. The description adds no format, default, or device-targeting nuance beyond what the schema documents.

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?

States a concrete verb+resource ('Set repeat mode'), which clearly distinguishes it from playback siblings like shuffle, seek, or set_volume. It does not, however, explicitly disambiguate from shuffle (the closest sibling) beyond the word 'repeat'.

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?

'Needs state' only restates the schema's required field; there is no when-to-use context, no note about whether the setting applies to the current device, and no mention of the shuffle sibling that a user might confuse it with.

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