Properties this account can reach

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds real value beyond them: the permission levels it returns and the trailing-slash / sc-domain: mismatch that manifests as a permissions error, which is a non-obvious behavioral trap. No pagination or volume notes, hence 4 not 5.

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?

Three sentences, no filler, front-loaded with what is returned and what the caller should do with it. The gotcha sentence earns its place by preventing a real failure mode.

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?

There is no output schema, and the description compensates by describing the return shape (properties plus permission level) and the exact format of the returned siteUrl strings. For a single-optional-parameter read tool, nothing an agent needs to call it 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 description coverage is 100% and the single account parameter is fully documented in the schema (including the pointer to list_accounts). The description adds nothing about parameter semantics, so the baseline 3 applies.

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+resource (every Search Console property this account can reach) and goes further by naming what is returned (permission level) and the exact enum values. It is clearly distinguishable from siblings like get_site, add_site and list_accounts, so an agent can pick it 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?

"Start here" and the statement that its siteUrl strings are the exact values every other tool wants gives clear sequencing guidance relative to siblings. It stops short of explicit when-not conditions or naming a competing alternative, so it is strong context rather than a full decision rule.

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