Cut to Active Speaker

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

Annotations already declare readOnlyHint=false and idempotentHint=false, so the mutation profile is known. The description adds useful behavioral context: detection uses real-time Fairlight audio levels, only listed guest inputs are eligible, and the host is excluded by default. It does not disclose what happens when no guest is speaking or whether preview state changes, which limits it below a 5.

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 definition is front-loaded with the core behavior, followed by params and examples, and is easy to scan. The Args section is somewhat redundant with the fully covered schema, but the examples justify their space by mapping natural language to parameter choices.

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 switching mutation with no output schema, the description covers the detection source, default input ranges, host exclusion, transition behavior, and ME bus. It omits edge-case behavior (e.g., silence, no eligible guests) that an agent might want before invoking it, but overall it is sufficient to call correctly.

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%, so the schema already documents all four parameters with defaults. The description's Args section largely restates the schema, though it adds a small semantic hint that 'only guests in this list are eligible' and reinforces host exclusion from detection.

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 opening sentence gives a specific verb and resource ('cut full-screen to the active speaker') and defines the selection rule (highest audio level from Fairlight VU data). This cleanly distinguishes it from manual switching siblings like atem_cut and atem_set_program without needing to name them.

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 examples show the practical invocation pattern, including how to get a dissolve via transition="auto". However, it never states when NOT to use this (e.g., when no guests are present) or explicitly routes to alternatives such as atem_set_program for manual selection.

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