Create AdMob ad unit

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

Annotations already indicate readOnlyHint=false, meaning it is a write operation. The description adds the auth scope requirement, which is useful context. However, it does not disclose other behavioral aspects such as return value, idempotency, or side effects, so it provides only marginal additional transparency.

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 description is extremely concise, with two sentences that each carry necessary information: the primary action and the required permission scope. There is no redundancy or fluff, making it easy for the agent to parse quickly.

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 tool has a moderately complex schema with a nested object and enums, and there is no output schema. The description provides the essential purpose and auth requirement, but it does not mention what the tool returns (e.g., the created ad unit ID). Given the schema covers parameters and annotations cover the read-only hint, the description is largely sufficient but could add a note about the response.

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?

The description itself introduces no parameter-specific details, but the input schema includes comprehensive descriptions for all 5 parameters (schema coverage 100%). Since the baseline for full schema coverage is 3, this is appropriate; the description does not add semantic value beyond the 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 clearly states the tool creates an ad unit under an app in the AdMob account using the specific verb 'Creates' and identifies the resource. It distinguishes itself from sibling tools like create_app or create_ad_unit_mapping by specifying exactly what entity is being created.

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?

The description implies the tool should be used when creating an ad unit under an app, and it notes the required OAuth scope (admob.monetization). However, it does not explicitly mention when not to use this tool or provide comparisons with alternative tools, so the guidance remains implicit rather than explicit.

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