Track

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

With readOnlyHint=false, the description usefully explains WHY: it is a read-like POST that consumes paid API credits, and it reassures that no social-platform publishing occurs. That is genuine behavioral context beyond the annotations, though it omits what happens if confirm is false/omitted and gives no indication of rate or quota behavior.

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 short sentences, front-loaded with the core purpose followed by the URL nuance and the cost/confirm constraint. The middle sentence is slightly awkwardly detached, but nothing is redundant.

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?

It covers credits and confirm, which is the main risk, but for a 4-parameter tool with no output schema and an empty required list it leaves a key gap: it never states that one of id or url is effectively mandatory. No return-value description is needed since no output schema exists, but the invocation contract is incomplete.

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 100%, so baseline would be 3, but the description adds a detail not present in the schema: album track URLs carrying an i= song id are accepted for the url parameter, clarifying the id-vs-url choice. It does not, however, clarify that at least one of id/url must be supplied despite required=[].

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?

States a specific verb and resource ('Retrieves public Apple Music song details') plus the input forms it accepts (id or URL), which cleanly separates it from apple_music_album, apple_music_artist, apple_music_search and the spotify_* siblings. The note about album track URLs with an i= song id further pins down scope.

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 gives a real precondition (consumes paid credits, confirm=true required), which is more than most definitions offer. However, it never says when to choose this over spotify_track or apple_music_search, and the phrase 'the specific approved credit-consuming research call' is vague about which calls qualify.

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