extract_stills_from_markers

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

With no annotations, the description fully details the behavior: scans track 1, extracts clips by marker color, creates a new timeline, copies grades, and sets bin location and start timecode. It does not mention error handling or cases like no markers found, but covers the main process well.

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 well-structured with a clear main sentence followed by details. The list of marker colors is slightly verbose but adds value. It is appropriately sized for the complexity.

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?

The description covers the essential workflow and parameters, given that an output schema exists for return values. It lacks details on potential errors or edge cases, but is sufficient for typical usage.

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 description provides extensive context for both parameters beyond the schema: marker_color includes a list of common values, and timeline_name explains naming convention. This compensates for the 0% schema description coverage.

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 ('Extract still frames from timeline markers') and the result ('create a new stills timeline'). It distinguishes itself from sibling tools like 'extract_qc_notes_from_markers' by specifying still extraction.

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 description does not explicitly advise when to use this tool versus alternatives, nor does it mention prerequisites or when not to use it. The usage is implied through the task description, but no guidance on choosing between siblings is provided.

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