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

Annotations already mark it read-only, and the description adds useful behavioral details beyond that: result ordering ('Hold-free patterns are listed first'), the scope ('this server can play'), and included safety notes about breath holds. No contradiction 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 front-loaded with the core action and resource, then adds a compact enumeration of the returned fields and the ordering guarantee. Every clause earns its place without redundancy.

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, the description fully covers what the agent should expect: phases, seconds, purpose, shapes, hold-free status, and safety notes. The ordering behavior is also disclosed, making the tool self-contained for a parameterless read-only call.

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?

The tool has zero parameters and the schema is empty, so there is nothing semantic to document. The baseline of 4 applies because there is no parameter ambiguity for an agent to resolve.

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 specific verb ('Lists') and resource ('VirWave breathing patterns this server can play'), then enumerates the details returned. This clearly differentiates it from the action-oriented siblings breathe and start_session.

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 makes it clear this is the tool for discovering available patterns and what they are good for, which implies use before or without starting a session. It does not explicitly name alternatives or exclusions, but the context is strong enough for an agent to route correctly.

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