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

Given annotations (readOnlyHint=true, openWorldHint=false), the description adds context about no catalog lookup and no quota cost, which aligns with the read-only nature. It does not contradict annotations and provides additional behavioral details.

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?

Two concise sentences that front-load the purpose and immediately convey core functionality. Every sentence adds value without 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?

Given the tool's simplicity and presence of an output schema, the description is complete. It explains what the tool returns, what it does not (no catalog lookup), and how to use it in context with other tools.

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 has 100% description coverage, but the description adds meaning by explaining the harmonic logic (same key, relative major/minor, adjacent +/-1, extended +7/-7). This goes beyond the schema's simple parameter description.

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 returns harmonically compatible keys for DJ mixing given a Camelot key, specifying the types of keys (same, relative, adjacent +/-1, and optionally +7/-7). It distinguishes from the sibling 'find_tracks_by_key' by emphasizing that this is pure music theory with no catalog lookup.

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?

Explicitly describes when to use (to get harmonic compatibility for DJ mixing) and when not to (no catalog lookup). Suggests pairing with 'find_tracks_by_key' for actual track retrieval, providing a clear alternative.

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