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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description's added value is the recommendation basis — same artist, related artists, same genre — and the fact that results are shuffled into a station, which tells the agent output ordering is not meaningful. Minor gap: it doesn't say whether the shuffle varies between calls or how the mix is weighted.

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?

A single compact sentence with the core action front-loaded and the selection criteria following as a natural clause. No redundant restatement of the title or name.

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 two-parameter read tool with a fully documented schema and no output schema, the description supplies the essentials: what the seed is, what drives similarity, and that ordering is randomized. Only the shape of the returned tracks and any pagination/truncation behavior are left unstated, which the absence of an output schema makes less critical.

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%, with both track_id (22-char catalog id) and limit (1–50, default 20) fully documented in the schema. The description adds no extra meaning about either parameter, so the baseline 3 applies.

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 gives a concrete verb-like framing ('Songs to play after a given song') plus the resource (songs/tracks) and the seed relationship, which separates it from get_track and search_catalog. It stops short of naming a sibling to contrast against, so it is clear but not maximally differentiating.

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?

'Songs to play after a given song' implies the use case (playback/radio continuation from a seed track), but there is no explicit when-not guidance and no mention of the genre/mood browsing siblings that could serve similar discovery needs. Usage is inferable rather than stated.

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