capcut_add_markers

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

No annotations are provided, so the description carries the full burden; it does disclose the key behavioral trait that calls are dry-run by default, which is genuinely useful. But it omits other important behavior: that writing requires CapCut to be closed (only stated in the schema), whether existing markers are overwritten, and whether the mutation is reversible.

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 short sentences with no filler: the action and payload come first, the dry-run default is front-loaded at the end as a warning. Every clause carries information.

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?

With no annotations and no output schema, the description must cover more ground. It handles the dry-run/write distinction and payload format, but does not describe what a dry-run returns, the CapCut-must-be-closed prerequisite (buried in the schema), or what happens to pre-existing markers.

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 67% and the schema already documents draft, dry_run, and the marker properties. The description adds a useful inline example of the markers array shape and its semantic purpose (chapter points), but does not explain units/constraints for t_s or the meaning of color/title beyond what the schema says.

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?

States a specific verb+resource ('Add timeline markers (CapCut time marks)') and grounds it with a concrete use case (chapter points for a YouTube description) plus the payload shape [{t_s, title, color}]. It is clearly distinguishable from siblings like capcut_add_text or capcut_add_transition, though it never names an alternative for the marker/chapter domain (e.g. capcut_export_chapters).

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?

Usage is implied through the example ('chapter points for a YouTube description') and the 'Dry-run by default' note, which tells the agent the safe starting mode. However, there is no explicit when-to-use/when-not guidance and no routing against the related sibling capcut_export_chapters, which an agent would plausibly confuse this with.

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