Prepare to replace a Performance Max asset group's status or final URLs. Saves a private draft after Google validate-only and a complete affected-resource snapshot; does not send the change. The confirmation tool is google_ads_asset_group_update_confirm; execution requires the user’s agreement in the conversation.
| Name | Required | Description | Default |
|---|---|---|---|
| body | Yes | ||
| customer_id | Yes | 10-digit Google Ads customer id. | |
| connection_context | No |
Changes observed during successful MCP inspections.
Input schema / properties / connection_contextAdded value: +{
+ "pattern": "^mctx_v1_[0-9a-f]{64}$",
+ "type": "string"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Goes well beyond the annotations by revealing the prepare/confirm workflow: it saves a private draft, runs a Google validate-only pass, captures a complete affected-resource snapshot, and does not send the change. This explains the real side effects (draft persisted) despite readOnlyHint=false, so the agent understands nothing is committed yet.
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 no filler, front-loading the action and scope, then the safety/sequencing constraints and the named alternative. Every sentence earns its place.
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 tool with no output schema, the description covers the workflow, side effects, and the confirmation path, which is what an agent needs. The remaining gap is parameter-level detail for the nested body, but the core calling contract is complete.
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% and the description mentions only the mutable fields ('status or final URLs'), adding some meaning over the bare schema. However, it gives no format, ID, or constraint detail for final_urls, status, or the nested body beyond what the schema already implies.
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 replace'), resource ('Performance Max asset group'), and scope ('status or final URLs'), which clearly differentiates it from the confirm sibling and from other asset-group tools. An agent knows exactly what this tool stages without reading the 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?
Explicitly states when to use it (to stage the change) and when not to expect a real mutation ('does not send the change'), and names the exact follow-up tool google_ads_asset_group_update_confirm. It even notes the precondition that execution requires the user's agreement in the conversation.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.