timecode_set

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

Without annotations, the description discloses the main effect (moving the playhead) and the format constraint. It does not cover edge cases like out-of-range timecode, but the core behavior is transparent.

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 wasted words. Each sentence adds essential information: action, format, and applicable pages.

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?

Given the tool's simplicity and no output schema, the description covers the key aspects. It could mention error handling for invalid timecode, but it's not necessary for a basic setter.

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 schema provides only a string type with no description. The tool's description adds the format 'HH:MM:SS:FF', which is critical for correct usage. This compensates for the schema's lack of parameter description.

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?

Clearly states the action 'Move the playhead' and identifies the resource (playhead position). Specifies the required format HH:MM:SS:FF and the pages where it works, distinguishing it from siblings like timecode_get.

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?

Explicitly lists the pages where it works (Cut, Edit, Color, Fairlight, Deliver), providing context for when to use. No explicit exclusions or alternative tools mentioned, but the guidance is sufficient for a simple tool.

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