Find similar tracks in the library

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

The readOnlyHint annotation already signals a safe read, and the description adds useful behavioral context by revealing the underlying similarity sources (Navidrome agents, Last.fm/Deezer/ListenBrainz, and co-occurrence in the user's own playlists) and the library restriction. No contradictions with annotations.

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?

Three concise sentences, each adding value. The description front-loads the core action and then provides necessary context on sources and constraints without waste.

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?

The tool has no output schema, and the description doesn't specify the response structure (e.g., what fields are returned for each track). It clarifies that results are library-only but leaves the return format implicit, which is a moderate gap for an agent.

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 75%, so the schema handles most parameter meaning. The description reinforces that 'track_ids' and 'artists' serve as seeds, but it doesn't clarify the undocumented 'limit' parameter or add meaning beyond the schema.

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 ('Expand') and identifies the resource ('seed tracks or artists') with clear scope ('Results are restricted to what is actually in the library'). It distinguishes this from siblings like search_tracks by explaining its similarity/co-occurrence mechanism.

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 conveys clear context: use this tool when you have seed tracks/artists and want library-restricted recommendations. It doesn't explicitly mention when not to use it or name alternatives, but the context is clear enough for an agent to decide.

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