Play on Spotify

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

The description does not contradict annotations. With readOnlyHint=false and idempotentHint=false, the agent can infer this is a mutating, non-idempotent action. The description adds the context of 'selected or active device' but does not disclose what happens if no device is available or whether playback state is replaced.

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, front-loads the core action, and contains no filler. Every word contributes meaning, making it highly concise and easy to scan.

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?

Output schema exists, so return details are covered. The tool is moderately complex with 5 optional parameters. The description covers the essential usage pattern, but omits behavior for edge cases like no active device, offset meaning, and what 'selected' implies. It is adequate but not thorough.

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?

Input schema has 0% description coverage, but the description adds crucial semantics by explaining the two mutually exclusive ways to specify the target (URI vs. item_type + item_id). However, it does not elaborate on offset or device_id semantics, leaving those to the schema defaults.

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 starts a Spotify track, album, artist, or playlist on a selected or active device, which is a specific verb+resource pairing. It distinguishes itself from sibling playback controls like resume, pause, next, and previous by explicitly targeting playback initiation.

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 concrete parameter guidance ('Provide a Spotify URI or both item_type and item_id') but does not explain when to choose this tool over alternatives like spotify_resume or spotify_next. The notion of 'selected or active device' implies context, but there are no explicit exclusions or alternative recommendations.

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