make_4_frame_idle_animation

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

Annotations only declare readOnlyHint=false and openWorldHint=false, so the description carries the behavioral burden and does so well: it enumerates the exact mutations (duplicates frame 1 to 4 frames, nudges `layer` down by `bob_pixels` on frames 2 and 4, sets uniform durations, adds a looping tag). It also discloses the return type (workflow_manifest.v1). It stops short of stating what happens to pre-existing frames or whether the operation is reversible/overwriting.

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 purpose sentence followed by the mechanics and the return value. Every sentence earns its place with no filler or restatement of the tool name.

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 mutating tool with no output schema, the description supplies the transformation steps, the touched parameters, and the return shape, which is enough to call it correctly. A note on interaction with pre-existing frames (overwrite vs. append) would close the remaining gap.

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 80% (defaults documented for layer, tag_name, bob_pixels, frame_duration_ms), so baseline is 3. The description adds genuine meaning by tying parameters to behavior: `layer` is the layer that gets nudged, `bob_pixels` is the downward offset amount, and frame_duration_ms maps to the 'uniform durations'. Only `filename` (and the exact effect of tag_name) is left unelaborated.

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 precise verb+resource+outcome: 'Turn a single-frame sprite into a 4-frame idle "bob" loop.' This is clearly distinguishable from generic siblings like add_frame, duplicate_frame, tween_cels, and smear_frame, which do not perform this specific one-shot idle-animation construction.

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?

The use case (single-frame sprite → idle bob loop) is implied clearly by the first sentence, so an agent can infer when it applies. However, no alternatives are named and no when-not guidance is given (e.g., what to do if the sprite already has frames, or how it differs from add_frame/duplicate_frame).

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