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

Goes well beyond the annotations (readOnlyHint=false, destructiveHint=false, openWorldHint=false) by disclosing the exact side effects: a private draft is saved after a Google validate-only check and a complete affected-resource snapshot, and nothing is transmitted. It also discloses a workflow/auth requirement (user agreement in conversation) that annotations cannot express.

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?

Front-loaded with the action, then the side effects, then the routing to the confirm tool. No filler sentences; every clause carries information an agent needs.

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 mutation tool with no output schema, the description covers the essential contract: validate-only, draft persisted, nothing sent, and the follow-up tool. It leaves open what the draft/prepare response contains (e.g., a draft identifier the confirm call needs) and how long the draft survives, which is a minor but real gap.

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 only 33%, and only customer_id carries a description. The description adds nothing about the nested body fields (campaign_id, match_type, text) or the connection_context token, so the majority of parameters remain undocumented in both schema and description.

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 and scope: prepare (not execute) the addition of a negative keyword to a Search campaign. It immediately distinguishes itself from google_ads_negative_keyword_add_confirm by naming that sibling, so an agent can route correctly 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?

Explicitly says this does not send the change and names the confirmation tool as the execution path, plus the prerequisite that execution requires the user's agreement in the conversation. The when-to-use and when-not-to-use conditions are both stated.

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