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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds useful context like 'currently including' (implies the content may change) and 'Call once' (suggests it's not meant for repeated polling). This adds some value beyond annotations but does not describe the return format or pagination, which is acceptable given an output schema exists. The description is consistent with annotations.

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 two sentences with no fluff. The first sentence front-loads the core purpose and scope, and the second sentence reinforces its primary role. Every word earns its place, and it is easy to parse quickly.

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 simple read-only tool with one optional parameter and an output schema, the description is fully adequate. It tells the agent what the tool returns, its scope, and that it is the primary library tool. The existence of an output schema covers return structure, and the limit parameter covers pagination. Nothing an agent needs to call it correctly is missing.

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 description coverage is 100% (the only parameter 'limit' is described with a range). The tool description does not add any parameter-specific details beyond what the schema already provides. Since the schema fully documents the parameter, the baseline of 3 is appropriate; the description adds no extra semantic value.

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 states a clear verb ('return'), a specific resource ('OffStereo library overview'), and a defined scope ('completed, unarchived shows'). It also distinguishes itself by calling out 'primary personal-library tool', which differentiates it from sibling tools like discover or music_today. The purpose is unambiguous and actionable.

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 says 'Call once' and labels itself as the primary personal-library tool, giving clear context that this is the go-to for a listener's own library. However, it does not explicitly state when to avoid this tool or name alternatives, such as when archived or in-progress shows are needed. The guidance is clear but lacks explicit exclusions.

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