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

Despite annotations only carrying a bland non-destructive/non-readOnly profile, the description discloses the real behavior: it runs Google validate-only, takes a complete affected-resource snapshot, saves a private draft, and explicitly does NOT send the change. This is exactly the context an agent needs and is consistent with destructiveHint=false and readOnlyHint=false.

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 tight sentences, with the core action and the safe-draft constraint front-loaded and the approval workflow following. No 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 prepare-stage tool with no output schema, the description covers the full lifecycle (validate, snapshot, draft, approval, confirm) so an agent understands the return behavior and next step. The only shortfall is the thin parameter coverage, which is a minor gap here.

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% (body.experiment_id and connection_context are undocumented) yet the description adds no parameter detail beyond implying an experiment is involved. It does not explain the experiment_id format, the customer_id, or connection_context, so it fails to compensate for the coverage gap.

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 ('Prepare to halt') and resource ('enabled Search or Display experiment'), and immediately distinguishes itself from the separate confirm step. An agent can tell it apart from google_ads_experiment_halt_confirm and google_ads_experiment_action_prepare without opening schemas.

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?

Clearly frames when to call it (precondition: an enabled Search/Display experiment) and the required follow-up ('Show the draft for explicit approval before calling google_ads_experiment_halt_confirm'). It routes to the correct sibling for execution but does not contrast against the other *_prepare experiment tools.

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