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

Annotations already declare readOnly/idempotent/non-destructive/openWorld, and the description still adds substantive behavior: an empty page is a successful result, private kits and unpublished submissions are never listed, and templates with source files can be large. It also enumerates the page envelope fields (count, hasMore, next_offset, availability, contentLevel, license, attribution, provenance), which goes well beyond the annotation baseline.

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 purpose, then args, returns, and examples, so the agent can stop reading early. It is somewhat long and the Args block largely restates a schema that is already 100% described, which is mild redundancy rather than waste.

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?

An output schema exists, yet the description still characterizes the page envelope and empty-page case, and it explains the list-then-fetch workflow with the sibling. Nothing an agent needs to invoke this correctly — namespaces, paging, search semantics, scope exclusions — is missing.

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 100%, so baseline is 3. The description adds value by giving concrete kind examples (animation, component-pattern, template, experience-pack) that make the 18-value enum navigable, and it restates the default page size and offset semantics. It does not add much on the query string beyond the schema's own wording.

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 ('Browse StyleKit's public asset catalogue') with explicit scope (public only, private kits and unpublished submissions excluded). It also names the paired sibling (stylekit_get_asset) and explains the kind/id handoff, so an agent can distinguish it from fetch-style tools without opening the schema.

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 a concrete usage flow: list, then call stylekit_get_asset with the returned kind/id, plus a worked example ('show me a pricing template') and a cost warning about fetching large templates. It does not, however, address the overlap with the sibling stylekit_search_styles even though the query parameter searches names/descriptions/tags, leaving one routing decision to inference.

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