marker_add

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only says 'Add' and mentions the marker/guide distinction; it does not reveal side effects, reversibility, permissions, or how adding a timeline marker differs behaviorally from adding a clip marker. This is a significant transparency gap for a mutating tool.

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 a single sentence with no filler and the key differentiator (time or clip, separate from guides) is front-loaded. It is concise, though perhaps too brief to carry full tool guidance.

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 has six parameters and zero schema descriptions, the description is incomplete for correct invocation. An agent would not know what marker_type values are valid, how clip markers differ from timeline markers in terms of parameters, or what the output schema represents. The presence of an output schema does not compensate for missing parameter and behavior context.

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 compensate for the undocumented parameters. It hints at a timeline/clip distinction that maps to position vs. track_id/clip_index, but it does not explain the role of label, comment, marker_type, or how the required position interplays with the optional parameters.

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 uses a specific verb ('Add') and resource ('timeline or clip marker'), and explicitly states that markers are separate from guides, distinguishing it from the sibling guide_add tool. An agent can immediately understand what this tool is for and what it is not.

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 parenthetical 'markers separate from guides' provides clear contextual guidance that this tool should be used for markers rather than guides, which is a relevant alternative in the sibling list. It does not explicitly name guide_add, but the distinction is enough to route the agent correctly.

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