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

Beyond the annotations (destructiveHint=true, idempotentHint=true), the description explains partial-update semantics, that an empty string destroys optional text, the publish toggle, the not_released feature-gate error code, required credential scope, and the 403 refusal for unclaimed sandbox workspaces. That is substantial context an agent cannot get from the structured fields alone.

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 the mutation semantics, followed by the two hard prerequisites (credential scope, claimed workspace) that would otherwise cause a failure. Every sentence carries a distinct constraint, though the prerequisite sentences are dense run-ons.

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 13-parameter mutation with no output schema, the description covers patch semantics, auth, feature gating and workspace-claim failures — the main ways a call goes wrong. It omits anything about return values and whether changing the subdomain interacts with existing DNS/domain records.

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; the description adds genuinely new semantics not present in the schema — that omitted fields are untouched and that empty strings clear text fields, plus that storefront_id can be sourced from list_storefronts. It does not explain the interplay of show_functions/show_negotiation with offer_tags/product_ids, so it falls short of a 5.

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 opening sentence names a specific verb and resource ('Change a storefront'), which clearly separates it from create_storefront, delete_storefront and get_storefront in the sibling set. It stops short of explicitly contrasting with those siblings, but the intent 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?

The description states the operative condition ('Only the fields you send change; an empty string clears optional text') and how to publish/unpublish, plus the gating condition 'only where the workspace has storefronts switched on'. It does not name alternative tools (e.g. delete_storefront for removal), so it earns a 4 rather than a 5.

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