spotify_library_stats

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

No annotations are provided, so the description must fully convey behavioral traits. It mentions the output (artist counts, playlist names, dates) but does not explicitly state that it is read-only, or disclose any side effects, auth requirements, or performance characteristics.

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 concise sentences with zero wasted words. The first sentence states the action and primary outputs, and the second explains the utility. It is well-structured and front-loaded.

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 zero parameters and an existing output schema (not shown), the description is mostly complete: it covers the purpose and value of the output. However, it does not clarify the scope of 'synced library' or the exact format of the summary, which might require additional context.

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 tool has no parameters, so the description adds meaning by detailing what the summary includes. This compensates for the empty schema, providing context beyond just the schema structure.

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 'Get a summary of your synced library — artist counts, playlist names, and dates', specifying the verb and resource. It distinguishes from siblings by focusing on high-level library stats, but does not explicitly differentiate from similar analysis tools.

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 use for understanding the library landscape for reasoning about vibes and groupings, but does not explicitly state when to use or not use this tool vs alternatives. No exclusions or contextual cues are provided.

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