spotify_set_volume

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

No annotations are provided, so the description carries the full burden. It states 'set volume' but does not disclose that this is a mutating operation affecting the active or specified device, whether it requires an active playback session, or what the response looks like. The optional device_id behavior is not explained, leaving ambiguity about the target device.

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 a single concise sentence with no filler. It front-loads the action and includes the critical range constraint. Every word earns its place, achieving maximum efficiency.

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 two-parameter tool with a fully described schema and no output schema, the description is minimally sufficient. However, it omits behavioral details like what happens if no device is specified, whether the volume change is immediate, and any error cases. An agent might not know that the optional device_id defaults to the active device, which is important for correct invocation.

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% and both parameters are fully described in the schema (device_id as optional string, volume_percent as integer 0-100 with min/max). The description adds no new semantic information beyond repeating the range, which the schema already provides. Thus, 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 states the action (set volume) and the resource (volume), with an explicit range (0-100). It distinguishes from sibling tools which control playback (pause, next, seek) rather than volume, so an agent can immediately identify this as the volume control 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?

While there is no explicit mention of alternatives, the purpose is unambiguous: use this to change the volume. The context is clear enough that an agent would not confuse it with other playback controls. However, it does not state any preconditions (e.g., must have an active device) or when not to use it.

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