List my tracks / playlists / likes / feed…

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

Annotations already cover read-only, idempotent, open-world, and non-destructive behavior. The description adds meaningful context beyond annotations by stating login is required and that results are paginated via next_href, which affects how an agent invokes and continues requests.

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 compact despite covering twelve kind variants, with a front-loaded purpose statement and a structured inline list. Every clause earns its place; there is no filler or redundancy.

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?

For a complex list tool with 6 parameters and 12 kind options but no output schema, the description covers the key operational facts: scope, login requirement, kind semantics, and pagination. A brief note about the response envelope would make it fully complete, but current coverage is strong.

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 83%, so the schema already documents sort, limit, access, account, and show_tracks well. The description adds real value by mapping each kind enum value to its concrete meaning (e.g., 'followings_tracks (recent tracks from users I follow)'), which the schema does not provide.

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 uses a specific verb ('List') with a clear resource ('the logged-in user's library and social data') and enumerates exactly what each kind returns. The 'logged-in user' scope distinguishes it from siblings like soundcloud_list_user_content without requiring schema inspection.

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?

It clearly states this tool operates on the logged-in user's data and requires login, which tells an agent when this is the right choice versus user-scoped or search tools. It does not explicitly name alternatives or exclusions, but the context is strong enough to route correctly.

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