playlist_template_apply

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

The annotations are minimal (only destructiveHint: false), so the description carries much of the behavioral burden. It does state the primary side effect explicitly ('Creates a new playlist and fills it') and adds that it uses 'your existing listening data', which is useful context. However, it does not disclose behavior around name conflicts, permission requirements, or whether the dry_run parameter actually prevents side effects, leaving the agent to infer these from 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?

The description is two sentences with zero filler. It front-loads the core purpose and template types, then clarifies the side effect. Every word contributes to understanding what the tool does, achieving high information density without unnecessary detail.

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 the tool's complexity (7 parameters, no output schema, many sibling playlist tools), the description is too thin. It does not explain how this differs from similar playlist generators, what a successful response looks like, or how the dry_run mode behaves. The agent would need to inspect schemas and infer relationships to use it correctly, which is a significant gap for a mutation-oriented tool.

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 100%, so the schema fully documents all 7 parameters. The description adds only marginal value by listing template options (which are already in the enum) and mentioning the data source. It provides no extra semantics for name, limit, public, dry_run, response_format, or description beyond their schema definitions, so the baseline of 3 is appropriate.

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 a specific verb ('create'), resource ('playlist'), and the template mechanism with concrete template names (focus, wind-down, gym, commute). It distinguishes itself from generic playlist creation by noting it composes from existing listening data. However, it does not explicitly differentiate from similar taste_* playlist-generating tools like taste_to_playlist or taste_era_playlist, so it's not a perfect sibling discriminator.

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 a use case ('instant mood/vibe playlist') but provides no explicit when-to-use or when-not-to-use guidance. It does not name alternatives or conditions that would make this tool preferable over others (e.g., using create_playlist for manual control or taste_* for more personalized mixes). The dry_run parameter is also not mentioned in the description, missing an opportunity for safer usage guidance.

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