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

With no annotations, the description carries the full burden, but it only states that the ad group will be paused. It does not disclose whether this tool actually creates the ad group, returns a draft operation, requires a follow-up confirm step, or what side effects occur. The word 'prepare' creates ambiguity rather than resolving it.

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?

The single sentence is short and front-loaded, but it is under-specification rather than effective conciseness. A five-parameter tool with no annotations and no output schema needs more than one terse clause to be useful.

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?

The description is inadequate for the tool's complexity. It lacks any explanation of the prepare semantics, return value, required follow-up, parameter semantics, or side effects. Given no annotations and no output schema, an agent cannot reliably know how to invoke this correctly or what to expect.

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 20% (customer_id only), and the description does not compensate. It adds no meaning for name, campaign_id, ad_group_type, or cpc_bid_micros, and does not clarify required vs. optional parameters or expected formats beyond the bare schema.

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?

The description names a specific verb-resource pair ('prepare creating' + 'ad group') and adds a key state qualifier ('paused'). This distinguishes it from other prepare tools by resource type, though 'prepare' itself is not fully defined.

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?

No guidance is given on when to use this tool vs. alternatives. The sibling list shows many prepare/confirm pairs, but the description never mentions that this is a staging step, whether a confirm tool exists, or when this should be used instead of other create/prepare tools.

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