add_timeline_marker

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

With no annotations provided, the description carries full burden for behavioral disclosure. It does not mention side effects (e.g., overwriting existing markers), required state (e.g., timeline must be open), or whether the operation is reversible. The reference to 'current timeline' is implicit but insufficient.

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 concise: a one-sentence purpose followed by a structured Args list with each parameter. No redundant information. Every line serves a purpose.

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 tool has an output schema (not shown), so return information may be covered there. However, the description does not mention what happens after adding a marker (e.g., returns a marker ID or success flag). For a simple add action, it is minimally adequate but could be more complete regarding the effect on the timeline.

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 0%, so the description must explain parameters. It names each parameter and provides brief context (e.g., 'Optional note text', 'Duration in frames, default 1'), but lacks details like allowed color values or constraints beyond examples. This adds basic meaning beyond the schema.

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 'Add a marker' with the resource 'to the current timeline at the specified frame.' This specific verb and resource differentiate it from sibling tools like add_clip_marker (for clips) and delete_timeline_marker (deletion).

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 implies use for adding timeline markers but does not explicitly state when to use this tool versus alternatives like add_clip_marker. No guidance on prerequisites or exclusions is provided.

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