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

The description adds meaningful behavioral details beyond the annotations: partial updates ('Only the settings that are passed are changed') and the home-soundbar fallback. These are consistent with readOnlyHint=false and destructiveHint=false, since the tool modifies settings but is not destructive.

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?

Three concise sentences with no filler. The first sentence states what the tool does, the second covers scope and fallback, and the third explains the partial-update behavior. Every sentence adds value.

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?

The description covers the effect, target hardware, fallback, and partial-update behavior, which is adequate for a simple settings tool. The main gap is the unresolved room optionality conflict between the schema's required list and its 'Omit for the default room' note, which could confuse an agent deciding whether to pass room.

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 description gives plain-language meaning for night_mode and speech_enhancement, both of which lack schema descriptions, and clarifies that only provided settings are changed. However, the schema marks room as required while its own property description says 'Omit for the default room,' creating a minor unresolved inconsistency.

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 opens with a clear verb and resource: 'Changes soundbar settings' and then names the exact settings (night mode, speech enhancement) with brief explanations. This distinguishes it from sibling tools like set_volume or set_mute, which target different audio parameters.

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 states it applies to Sonos soundbars, defines fallback behavior when the named room has no soundbar, and clarifies that only passed settings are changed. It does not explicitly contrast with sibling tools or state when not to use it, but the context is clear enough for an agent to select it appropriately.

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