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

Annotations already declare readOnlyHint=false, idempotentHint=false, openWorldHint=true, destructiveHint=false, and the description adds crucial context beyond them: a newly added property is UNVERIFIED and shows no data, the verification code is visible only to the signed-in owner, and confirm=false is a preview while confirm=true commits.

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 and almost every sentence carries actionable content, but the verification walkthrough is dense and somewhat run-on ('Next step after adding: the user opens the property...picks the DNS TXT method...'). Long but not wasteful.

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, so return values need not be described. With that covered, the description supplies the property-format choice, preview/commit semantics, and the full post-add verification path — nothing an agent needs to call this correctly 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 0%, so the description carries the full burden — and it delivers. site_url is explained with two concrete formats ('sc-domain:example.com' covering all subdomains, recommended; vs 'https://www.example.com/'), and confirm is defined as preview vs add.

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 ('Adds a website as a property to the connected Search Console account') and differentiates from the sibling gsc_list_sites by noting that a never-added site 'does not show it'. An agent can distinguish this from connect_search_console or the generic add_site without opening any 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 the trigger condition (site absent from gsc_list_sites) and the downstream workflow: open the property, pick DNS TXT, provide the google-site-verification value, and route to the sibling site_dns_records (mode='add', type='TXT') when DNS is on Opus Growth. It also explains when to use confirm=false vs confirm=true.

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