Opentoonz Tween Frames

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

With no annotations, the description carries the full burden and does well: it discloses that the tool writes a rendered PNG sequence to <workspace>/drawings/<level_name>.%04d.png, states the naming pattern, and explains anchor/neutral-field behavior. It does not mention overwrite semantics or that an existing sequence may be replaced, which is a notable gap for a file-writing 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?

Front-loaded with the core action, then the necessary JSON shape and field semantics. The embedded object example is justified given the empty schema, though the description could trim a little redundancy in the anchor sentence.

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 9-parameter, nested-object, file-producing tool, the description covers the hard parts (object shape, anchor semantics, output path, follow-up tool) and an output schema exists so return values need no prose. Remaining unstated items (resolution/background defaults, overwrite behavior) are minor but real.

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 0% and the start/end params are opaque additionalProperties objects, so the description's inline shape (path, xy, scale, rotation, opacity) is essential and well supplied, plus the semantic detail that xy is the CENTRE and omitted fields stay neutral. It leaves width, height, background and the frames unit unexplained, keeping it 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?

States a specific verb and resource ('Tween one drawing from a start pose to an end pose'), describes the produced artifact, and explains why the tool exists (GUI-only auto-inbetweening). An agent can distinguish this from siblings like opentoonz_draw_frames or opentoonz_render_frame immediately.

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 routes the agent to the follow-up sibling opentoonz_import_images_as_level and clarifies this tool's role versus the GUI workflow. It does not state exclusions (e.g. when not to use it vs opentoonz_draw_frames for a fixed pose), so it stops short of a full 5.

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