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

Annotations already cover the safety profile (readOnlyHint=true, openWorldHint=false), and the description adds genuinely useful behavior: it enumerates the returned artifacts (anatomy tree, motion, states, webm, tokens) and discloses fallback behavior when a requested type is missing. Marketing framing dilutes it slightly, but the extra context is real.

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?

Purpose is front-loaded in the first sentence and bullets aid scanning, but the text is bloated with promotional filler ("Mozaika's wedge", "A complete, uncopyable, measured build kit") and an exhaustive catalog that is partly redundant listing.

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?

There is no output schema, so the description must describe returns — it does so in detail. However, with zero schema description coverage, the unexplained 'site' parameter and absent tie-breakers against siblings leave the definition incomplete for reliable invocation.

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% for both required parameters, so the description must carry the full burden. It compensates well for recipe_type by listing accepted values and families, but the 'site' parameter is never explained semantically beyond appearing in the examples, leaving a real gap.

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?

The description states a specific verb+resource (fetch a measured spec + code 'build kit' for a piece of UI) and details the three content families it returns. It is clear what the tool does, but it never names or contrasts itself against close siblings like get_component, get_asset_pack, or compare_recipes, so the agent must infer the boundary.

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?

It gives an explicit usage trigger ("Use for 'build a <thing> like <product>'") with concrete call examples, which is strong context. It stops short of exclusions or naming alternatives, so it does not reach a 5.

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