spotify-mcp

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It successfully adds the Premium requirement and enumerates the three valid states, but does not disclose side effects (e.g., whether this affects the current session immediately) or rate limiting 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 consists of two short sentences with zero redundancy. The first sentence delivers the function and valid parameter values, while the second delivers the critical Premium constraint. Every word 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?

Given this is a simple single-parameter setter with an output schema (so return values need not be described), the description covers the critical gaps: valid parameter values and the Premium requirement. It could be improved by briefly explaining what 'context' means (album/playlist), but it is sufficient for invocation.

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 0% description coverage with only a 'State' title and no valid values documented. The description compensates perfectly by explicitly listing the three valid string values ('off, context, or track'), providing essential semantic information that the schema completely lacks.

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 specific action ('Set repeat mode') and the valid values ('off, context, or track'), providing a clear verb-resource pair. However, it does not explicitly differentiate from sibling playback control tools (like spotify_toggle_shuffle) beyond the specific function name.

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 a critical usage constraint ('Requires Premium') which informs the agent about authentication requirements. However, it lacks explicit guidance on when to use this tool versus other playback control siblings or prerequisites like active playback sessions.

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