create_icon_set

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

Annotations only declare readOnlyHint=false and openWorldHint=false, so the mutation hint is covered, but the description adds real value by disclosing the return artifact: a `workflow_manifest.v1` manifest of kind "icon_set" with per-icon regions exposed as slices under `sprite.slices`. That return contract matters since no output schema exists. It does not state persistence behavior or whether an existing set is overwritten.

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?

Two tight sentences: the scaffolding behavior and cell naming come first, the return shape second. Nothing is padded. The phrase 'for easy atlas export' earns its place as rationale, though it is not strictly required.

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 creation tool with no output schema, explaining the returned manifest is genuinely helpful and largely closes the return-value gap. What remains missing is the semantics of `columns` and `icon_size` (grid layout and cell pixel dimensions), plus whether the scaffold writes to a sprite file on disk. Adequate but with clear gaps.

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 50%, and the description compensates for `count` by describing cells and their naming scheme (icon_0, icon_1, …), matched to slices. However, `columns` and `icon_size` are left entirely to the schema, whose only descriptions are 'Default: 16.' — no meaning or units are added.

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 (scaffold) and resource (icon set) with concrete structure: a grid sheet of `count` cells, each a named placeholder slice. This clearly distinguishes it from siblings like create_sprite or create_tileset_project. It stops short of naming an alternative, but the purpose itself is unambiguous.

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?

No when-to-use guidance, prerequisites, or comparison to alternatives anywhere in the text. It does not tell the agent when scaffolding an icon set is preferable to creating a sprite and adding slices manually via add_slice. Usage must be inferred from the name alone.

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