create_anim_sequence

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

Goes well beyond idempotentHint=true by spelling out the exact idempotency semantics (already_existed=true, saved=false, length/rate not applied, nothing saved) and the failure mode (success=false, saved=false, save_error, asset left in memory only). It also discloses the derived data model rounding of frame_rate and round(length_seconds*fps).

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-loads the core action and stays to one dense paragraph with no filler, but the middle sentences pack idempotency, error handling and derived-state details tightly enough that it reads as a wall of clauses rather than cleanly separated points.

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?

No output schema, yet the description enumerates the full return shape, covers success/failure/idempotent paths, and points at the follow-up tools for filling and inspecting the asset. Nothing material for correct invocation 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 100% so the baseline is 3, but the description adds real value: skeleton_path defaults to the engine SkeletalCube_Skeleton (not stated in the schema), frame_rate is rounded to whole fps, and length_seconds is converted to a frame count. Package path composition (package_path/anim_name) is also clarified.

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 (create a UAnimSequence), names the parent binding (USkeleton at skeleton_path) and the save behavior in the first clause. It is unmistakably distinct from siblings like create_anim_montage, create_blend_space, or create_pose_asset.

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?

Explicitly tells the agent what this tool does not do (no bone tracks or curves) and routes to alternatives: add_anim_bone_track / add_anim_float_curve to populate it, get_anim_sequence_info to inspect it. It also defines the error conditions (wrong asset class, unknown skeleton) that select against proceeding.

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