capcut_add_filter

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

With no annotations, the description carries the full burden and does disclose two key traits: it overwrites the clip's existing filter (a destructive side effect) and it defaults to a dry-run. Missing are failure behavior (e.g. no clip at start_s) and permission/environment requirements, which are only hinted at in the schema's dry_run text.

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?

Three tight sentences, front-loaded with the action and target, followed by the overwrite warning and the dry-run default. No filler and no repetition of schema constraints beyond what adds meaning.

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 7-parameter mutation tool with no annotations and no output schema, the description covers purpose, target scoping, destructive semantics, and the dry-run safety valve. Gaps remain around the undescribed name/track parameters and error conditions, but nothing essential for a correct call is missing.

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 coverage is only 43%, so the description has to compensate and largely does: it pins start_s to "the segment at start_s", bounds intensity to 0-100, and gives a concrete resource_id example (7668224318974823701 = Rollo vintage, free) plus its meaning. The name and track parameters remain unexplained anywhere, which keeps this below 5.

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 names a specific verb+resource ("Put a CapCut filter") and narrows the scope to "one video clip (the segment at start_s)", which distinguishes it from sibling mutators like capcut_add_effect, capcut_add_sticker, or capcut_add_transition. An agent can tell what this does without opening the schema.

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 rather than stated: you apply a filter to an existing clip identified by start_s, and the operation replaces any existing filter. There is no explicit guidance on when to prefer this over capcut_add_effect or capcut_insert_preset, and no prerequisites (e.g. that CapCut must be closed) are given in the description.

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