Set effect

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

The description reveals that the tool switches the device into effect mode and starts playback, adding context beyond the annotations (readOnlyHint=false). However, it doesn't disclose potential side effects like whether the current mode is interrupted or what happens on an invalid effect ID. With sparse annotations, the description partially compensates but not fully.

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?

Two concise sentences: the first states the purpose, the second gives a key prerequisite. No fluff, front-loaded, and every word earns its place.

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 write tool with no output schema, the description covers the core usage, effect ID semantics, and a required lookup step. It doesn't mention response format or error handling, but it's sufficient for an agent to invoke it correctly given the schema and sibling context.

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%, with both properties already described in the input schema. The description reinforces that IDs are 0-based and suggests listing effects, adding marginal value beyond the schema. The baseline of 3 applies because the schema does the heavy lifting.

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 tool selects a predefined effect by numeric ID and switches the device into effect mode to play it. This differentiates it from sibling tools like set_color and set_movie by explicitly naming the effect mode and the list_effects prerequisite.

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 provides an explicit usage guideline: 'Call list_effects first to see how many effects exist (ids start at 0).' This tells the agent when to use the tool (after listing effects) and implies the sequence. It doesn't explicitly mention alternatives, but the context is clear enough.

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