resolve_add_marker

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

No annotations are provided, so the description carries the behavioral disclosure burden. It usefully reveals the legacy frame=0 playhead behavior and explains that other frame values are timeline-relative, which goes beyond the schema. It does not describe side effects, overwrite behavior, or duration units, but the core quirk is disclosed.

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, both purposeful: the first defines the operation and the critical frame behavior, the second routes to an alternative. It is front-loaded and contains no filler.

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 output schema exists, so return values do not need explanation. The description covers the core operation and the important frame=0 quirk, but for an unannotated five-parameter tool it omits the relationship to resolve_add_marker_at_playhead and does not clarify duration semantics. It is adequate but not fully complete.

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 missing parameter documentation. It only explains the frame parameter's playhead-vs-timeline behavior; name, note, color, and duration rely entirely on their names and defaults. Duration's units and boundary behavior are left ambiguous.

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 operation: 'Add timeline marker' with a specific verb and resource. It also adds frame-position semantics that differentiate default playhead placement from timeline-relative placement. It does not explicitly contrast with the closely named sibling resolve_add_marker_at_playhead, which costs it full marks.

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 gives one explicit routing instruction: use resolve_create_chapter_markers to explicitly address frame zero. However, it does not mention the overlapping sibling resolve_add_marker_at_playhead or provide broader guidance about when to prefer this tool over that one.

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