Draft attaching a shared set

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

Annotations only say readOnlyHint=false, destructiveHint=false, openWorldHint=true, which alone would leave the agent unsure whether this mutates state. The description resolves that by explaining it returns a PREVIEW with a plan_id and that nothing changes until confirm_and_apply applies it — a two-phase workflow 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 and the preview caveat, then the mechanism, use case, and apply step. Efficient overall, though the trailing Google Ads API documentation URL is low-value filler for an agent.

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 values need no explanation, and the description covers the key workflow context (preview -> confirm_and_apply) that an agent needs to call this correctly. Nothing essential 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 description coverage is 100%, so the schema already documents shared_set_id, campaign_ids, and customer_id (including dedup behavior). The description adds conceptual context ('campaigns inherit the shared set's criteria') but no parameter-level detail beyond the schema. Baseline 3 is appropriate.

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 ('Attach an existing shared set to one or more campaigns') and immediately scopes it as a preview. It is clearly distinguishable from detach_shared_set_from_campaigns and get_negative_keyword_list_campaigns, both named or implied in siblings.

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 a concrete primary use case ('attach a shared negative keyword list to newly-built campaigns') and points to get_negative_keyword_list_campaigns for inspecting existing attachments. It does not explicitly state when not to use it (e.g. vs attach_brand_list_to_campaigns), but the context is clear enough to route correctly.

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