Plan Active Speaker Reframe

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

Annotations already declare readOnlyHint/idempotent/destructiveHint=false, so 'Local-only; never changes Premiere' reinforces rather than establishes safety. The genuinely additive disclosure is that it 'Returns framings, switches, keyframes, and apply routes' — telling the agent this planner hands off to a separate apply step, which is non-obvious workflow context beyond the 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?

Two sentences, no filler: the first front-loads the purpose and both output modes, the second covers the return and the local-only constraint. Every clause 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 an 11-parameter, nested-object planning tool with an output schema, the description covers the essential framing: inputs (word timeline, speaker regions), outputs (framings, switches, keyframes, apply routes), and safety. Nothing critical is missing, though it could have noted that a word timeline bound to a transcript revision is required.

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% across all 11 parameters, including the layout enum semantics, defaults, and bounds, so the schema already carries the parameter burden. The description only gestures at the layout alternatives ('active-speaker ... or a static stacked/split') without adding syntax, constraints, or default behavior beyond what the schema documents. Baseline 3 applies.

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 gives a specific verb+resource ('Plan an active-speaker vertical reframe') and clarifies the mechanism (Motion Scale/Position keyframes that follow whoever is talking), distinguishing it from the plain 'auto_reframe_sequence' sibling. It also names the alternate output mode (static stacked/split layout) up front, so an agent can tell immediately what family of tool this is.

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 states the required source material ('from a word timeline and static speaker regions') and the non-destructive posture, which implies a plan-then-apply workflow. However it never explicitly says when to pick this over siblings like auto_reframe_sequence or plan_speaker_checkerboard, and the active_speaker vs stacked/split choice is left to the layout enum rather than routing guidance.

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