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

Annotations already flag destructiveHint=true, and the description adds substantial context beyond that: recovery preserves a saved note, an active siteId preserves profile and note without overwriting, an active URL returns site_already_exists, non-idempotent staged completion, and that no scan is launched. This is exactly the behavioral detail annotations cannot convey.

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-loads the core action and shares the high-value recovery/idempotency rules first. It is dense and repeats the 'use update_site to edit' pointer several times, but nearly every sentence adds a distinct rule rather than filler.

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 complex creation tool with nested objects, six parameters, and recovery branches, the description covers inputs, alternatives, error cases, idempotency, and side effects; the output schema handles return values, so nothing critical 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 coverage is only 33%, so the description carries real weight and does: it explains url vs siteId mutual exclusion, clientId placement semantics, strategicGoal as an initial note, and models as account-default patching with null-clears. The nested businessProfile fields are only asserted as required rather than explained, leaving a small gap against the low coverage.

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 ('Save the business profile ... complete brand Site setup in one call') and clearly separates itself from update_site as the editing alternative. An agent can tell what this does and how it differs from siblings without opening a 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 explicit routing: exactly one of url or siteId, no separate research/confirmation tool is required, use update_site to edit, retry a setup_failed ID through its original URL, and inspect inventory/details before retrying after uncertainty. When-to-use and when-to-switch are both covered.

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