Add Audio Track to CapCut Draft

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

Annotations already disclose readOnly=false and destructive=false. Description adds that it adds to the timeline and returns JSON confirmation, but does not provide richer behavioral context (e.g., side effects, mutation details). No contradiction with annotations.

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?

Front-loaded with a clear summary and organized Args/Returns sections, but the Args list duplicates parameter descriptions already present in the schema, adding redundancy. It is acceptable but not as concise as it could be.

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?

For a mutation with 8 params and no output schema, the description covers the essential operation, parameter roles, and return type. It also explains extra_params passthrough and gives examples, though it omits error scenarios and detailed return structure.

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 100%, and the description largely paraphrases schema definitions (e.g., start, end, volume, speed, effects). It adds minor clarifications like 'end defaults to full clip length' but those are already in the schema, so little new value.

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?

Description states 'Add an audio clip (music, voiceover, sound effect) to an existing draft's timeline' with a specific verb and resource, and clearly distinguishes from siblings like capcut_add_text, capcut_add_video, etc.

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?

Indicates the audio is added to an 'existing draft' and that draft_id comes from capcut_create_draft, providing clear context. However, it does not explicitly state when not to use this tool or name alternatives, though siblings are obvious.

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