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

Because no annotations are provided, the description carries the burden of behavioral disclosure. It reveals the 1-credit cost, the fact that empty results and failures are never charged, and the default fresh fetch versus free cache-hit behavior — all beyond the schema. It does not mention auth, rate limits, or detailed error semantics, but the most operationally relevant behavior is covered.

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 concise and front-loaded, starting with the resource and return fields, then cost and cache policy in a compact second sentence. The parenthetical "(1 credit)" right before "Costs 1 credit." is slightly redundant or ambiguous, so it is not perfectly clean, but there is almost no filler.

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?

With no output schema and no annotations, the description provides essential calling context: the main return fields, the credit cost, and the free-cache and no-charge-on-failure behaviors. It could add a sibling comparison or a fuller return-shape description, but for a straightforward fetch tool with a complete input schema, the core context is covered.

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?

All three parameters — url, raw, and cache — are already described in the schema, which has 100% coverage. The description mostly restates the well-documented cache behavior and adds no new meaning for url or raw. The schema does the heavy lifting, so the baseline 3 is appropriate.

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 identifies the tool as a Spotify album lookup and lists the normalized fields it returns, including tracks[], playCount, joinable artists[], releaseDate, and explicit. It distinguishes itself from sibling Spotify tools by naming the album resource, though it lacks an explicit verb such as "fetch" or "get" and does not name alternatives.

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 gives operational guidance for caching — pass cache=true for a free 24h hit — but no guidance on when to use this tool versus spotify_track, spotify_artist, or spotify_search. An agent must infer usage from the tool name alone; there are no exclusions, alternatives, or conditions for selection.

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