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

Annotations already cover read-only, idempotent, non-destructive and open-world behavior, and the description adds substantive context on top: licensing/contentLevel gating of source, the structured unavailable error when a remote source is down, the rule that a download URL is not treated as source code, and missingFiles reporting for unmatched paths. This is behavior an agent cannot infer from the annotations or schema.

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?

Well structured and front-loaded: the retrieval rule comes first, then Args, Returns, and three worked examples. It runs somewhat long and restates the includeSource behavior in two places, but nearly every sentence carries information an agent needs to call the tool correctly.

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 4-parameter read tool with an output schema, the description covers the retrieval contract, licensing limits, failure mode, and size-control strategy. Since an output schema exists it does not need to detail return values, and its brief note about structured JSON plus provenance is sufficient.

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 goes further: it explains that kind is the namespace produced by stylekit_list_assets, that id must be exact within that namespace, that files omitted means all files, and that unmatched paths surface as missingFiles. That error semantics for a parameter is not present in the schema.

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 with its scope qualifier: 'Retrieve one public asset by its exact kind and id.' It also routes the agent to stylekit_list_assets for obtaining the kind/id pair. It does not differentiate from specialized siblings like stylekit_get_style or stylekit_get_style_tokens, which overlap with several of the 18 namespaces in the kind enum.

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?

Gives concrete when-to-use guidance: use includeSource:false or files to keep responses small, use files for a subset of template sources, and get kind/id from stylekit_list_assets. It never states when this generic tool should be preferred over the narrower sibling getters, so the alternative-selection rule is left implicit.

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