Create AdMob ad unit

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

Annotations indicate destructiveHint=true and readOnlyHint=false. The description aligns, noting creation is performed unless dryRun is true. It adds the allowlist requirement and preview capability, which are beyond annotation scope. No contradiction.

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?

Two sentences deliver purpose, allowlist note, and dryRun guidance. Every sentence adds unique information with no redundancy.

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?

Despite no output schema, the description covers key aspects: creation, allowlist, dryRun. With 8 parameters fully described in schema and annotations, this is sufficient for a creation tool. Missing return value detail is a minor 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 coverage is 100%, but the description adds value by explaining dryRun's default behavior ('operation runs after MCP client asks you to confirm') and publisherId defaults. This augments schema descriptions.

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 name and title clearly indicate creating an ad unit. The description specifies 'under an app (v1beta)' and mentions the dryRun option. Among sibling tools, this is the only ad unit creation tool, so it is well-distinguished.

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 states that the method is allowlisted and that a 403 means no access. It also advises using dryRun to preview requests. While it does not explicitly compare to siblings, the context implies it is for creation when access is granted.

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