marker_add_transition

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

No annotations are provided, so the description must convey behavior. It explains the primary effect (jump to destination) but does not disclose potential side effects (e.g., overwriting existing markers, idempotency) or error handling for invalid GUIDs. It provides context about argument origins, but not the full behavioral profile.

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: first explains purpose and behavior, second lists parameters with brief explanations. Front-loaded with the key insight (jump to destination). No superfluous text.

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 core usage, including parameter origins and position constraint, and clarifies the destination type. It doesn't discuss edge cases like invalid targets or idempotency, but for a simple add operation this is adequate. The lack of output schema is acceptable as the tool likely returns a confirmation.

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 has 0% description coverage, but the description adds meaningful context for all three parameters: track_target's origin (from event_add_marker_track), position constraint (>= 0), and destination_target's source types (NamedMarker or LoopRegion). This goes beyond the schema's titles and helps the agent understand argument semantics.

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 'Add a transition marker' and explains the behavior: 'when playback crosses this point, the timeline jumps to the given destination.' This is a specific verb+resource combination that distinctly separates it from sibling tools like marker_add_named or marker_add_region, which serve different purposes.

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 clear context on what the tool does and references where the track_target and destination_target GUIDs come from (events/marker tools). It implies when to use it (for jump transitions) but does not explicitly contrast with other marker tools or state when not to use it. Still, the behavior is specific enough to infer usage.

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