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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint=false, so the safety profile is covered. The description adds the return behavior (up to three songs, best first, playable card where supported), which is useful, but does not specify fallback or error 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?

The sentence is front-loaded with the core action, but the parenthetical enumeration of all ten moments is lengthy and somewhat redundant with the schema enum, making the description less efficient than it could be.

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 that annotations cover safety and the schema documents parameters, the description is nearly complete: it explains the input options and return format. The only omission is how ties or conflicts between moment and description are handled. No output schema, so return-value details are useful.

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% – both properties have descriptions and the enum values are named. The description's list of moment meanings mirrors the enum labels with brief explanations, adding some interpretive value, but largely repeats structured data. 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?

Specific verb ('Recommend') and resource ('Boots & Bassline songs') with the moment/person scope clearly stated. It is distinguishable from sibling tools, which are all get/list operations – this is the only recommendation tool.

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?

Explains that either a curated moment or a free-text description is needed, and enumerates the moments. It does not state when to prefer the enum over a description or what to do if both are provided, but the usage context is clear.

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