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

Beyond the annotations, the description discloses the dry-run nature (nothing is created), the duplicate-detection behavior, the quota rule (one free listing per workspace), and the specific error signal pro_required on a non-Pro site. The only tension is that readOnlyHint=false while the description stresses no creation occurs — this is plausibly explained by the outbound Google call (openWorldHint=true) rather than a write, so it is not a contradiction, but the description does not clarify why the call is not read-only.

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?

The core action and its non-creation guarantee are front-loaded, and every sentence carries operational content (duplicate handling, real-details rule, quota, Pro warning). It runs long as a single dense block, and the quota/Pro sentences could be tightened, but nothing is 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?

There is no output schema, and the description partially compensates by describing what happens on a match ('show them', requestAdminRightsUri) and the pro_required failure. For a tool with a nested 5-parameter listing object it leaves the success-path return shape and the setup_id/connection_id distinction unexplained, but the decision-relevant behavior is covered.

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 80% and the schema documents site_id, setup_id, connection_id, user_goal, and the primaryCategory reference to search_google_categories. The description adds no meaning about any parameter — notably it does not explain setup_id vs connection_id, which are the two ambiguous sign-in paths. Baseline 3 is appropriate given the schema already carries most of the burden.

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 description states a specific verb and resource combination: 'Validate a NEW listing with Google without creating it', plus a secondary function of finding existing listings that may already be this business. The phrase 'without creating it' implicitly separates it from create_google_listing, and 'NEW listing' plus the duplicate check distinguishes it from get_google_business_status and list_google_locations.

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?

It gives explicit when-to-use ('before creating it'), what to do when a match exists (request access via requestAdminRightsUri rather than create a duplicate), a hard prohibition ('never test with a made-up business'), and a prerequisite to communicate (tell the owner that ongoing management requires Pro). Alternatives and exclusions are both named.

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