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

Annotations already declare destructiveHint=true and idempotentHint=false, and the description goes well beyond them: it explains the two-call preview/confirm_token flow (token valid 10 minutes), that the first call changes nothing, that only this server's monitor is affected, and that it never counts toward the monthly change limit. That is meaningful behavioral context the annotations cannot carry.

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?

Purpose is front-loaded in the first sentence, then mechanics and operations follow in a logical order. The single dense paragraph is efficient, though the nested procedural detail makes it slightly run-on.

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?

With no output schema, the description carries the return burden and does explain the preview/confirm_token result of the first call. Minor gap: it doesn't describe what else the preview contains or error behavior, but nothing essential to invoking it is missing.

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 100%, but the arguments object is free-form (additionalProperties: {}), so the schema alone is thin. The description adds real meaning: arguments carry the operation's fields plus 'connection' when several ad accounts are connected, and confirm_token on the second call.

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 and resource ('Deletes this server's monitors of a Google Ads account') and immediately bounds the scope ('Nothing in Google Ads changes'). This distinguishes it clearly from siblings like google_ads_update, google_ads_read, and meta_ads_delete.

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?

Gives concrete routing guidance: use google_ads_delete with action=execute and tool_name=google_delete_monitor, get schemas via get_tool_schema, and list operations via google_ads_read {'action':'list_tools'}. It doesn't explicitly state when to choose delete over update, but the operating context is clear.

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