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

The annotations already cover the safety profile (read-only, non-destructive, open-world), so the description only needs to add context. It adds two useful facts: results are permission-scoped to what the user can access, and the key output is property_id consumed by downstream tools. It doesn't discuss volume, pagination, or empty-result behavior, which is a minor gap for a listing call.

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?

Two sentences, front-loaded with the action, followed by the dependency hint. Every clause earns its place; nothing is repeated from the title or schema.

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 shape need not be described, and annotations cover safety. The description is close to complete for a zero-parameter discovery tool, with only a small gap around what happens when the user has no GA4 access.

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?

There are zero parameters, so parameter semantics falls back to the baseline of 4. The description correctly implies the call scope (the current user's access) without inventing parameters that don't exist.

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 (List) and resource (Google Analytics 4 accounts and properties), plus a scope qualifier: only what the user can access. It also distinguishes itself from the other GA4 tools by naming its role as the prerequisite that yields property_id.

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?

"Call this first to get the property_id the other GA4 tools need" gives an explicit ordering rule and names the condition that selects it. No exclusions are needed because there is no competing sibling that lists GA4 properties.

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