set_clip_join_tool

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

With no annotations, the description carries the full behavioral burden and does disclose the core mutation effects: crossfade sets left fade-out and right fade-in to length_ms, cut zeroes both fades, and fade sets or keeps both. It does not state permission requirements, reversibility, undo behavior, or whether the edit is immediately applied, so it is useful but not exhaustive for a mutation tool.

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?

The main operation is front-loaded, and the alternative-tool guidance is placed usefully near the end. The parenthetical TOOL_TIMEBASE: na is cryptic and adds little, while the mode explanations are dense but relevant.

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?

Given no annotations, 0% schema description coverage, and five parameters, the description should be more complete. It covers the core join/fade behavior and sibling routing well, but leaves project_path and parts of the parameter semantics unexplained; the output schema removes the need to document return values.

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% with five parameters, so the description must compensate. It explains mode values and length_ms behavior for crossfade, including the tighten.crossfade_ms default, but left_clip_id, right_clip_id, and especially project_path receive no additional semantic detail.

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 and resource: setting the join between two neighbouring clips with mode and fades. It also explicitly distinguishes itself from a sibling, set_join_mode_tool, by saying to prefer this tool because it affects both mode and fades.

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?

Gives explicit when-to-use guidance by naming the alternative set_join_mode_tool and the condition that selects this tool: that alternative changes mode only and leaves a crossfade with no fades to blend. Mode semantics further clarify the usage choice.

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