Google Ad Manager MCP Server

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

With no annotations provided, the description carries the full burden. It discloses that this is a mutation tool (changes status from NEEDS_APPROVAL), mentions the workflow dependency, and describes the outcome ('allow delivery'). However, it doesn't cover permissions needed, error conditions, or rate limits.

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 efficiently structured with a clear purpose statement, context, and separate Args/Returns sections. Every sentence adds value without redundancy, and the information is front-loaded appropriately.

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?

For a mutation tool with no annotations but an output schema, the description provides good context about the workflow, prerequisites, and expected outcome. The presence of an output schema means the description doesn't need to detail return values, but could better address error cases or permissions.

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?

With 0% schema description coverage and only one parameter, the description adds essential meaning by explaining what line_item_id represents ('The line item ID to approve'). This compensates well for the lack of schema documentation, though it doesn't provide format or validation details.

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's purpose with a specific verb ('Approve') and resource ('line item'), explicitly mentioning that it's for line items in NEEDS_APPROVAL status. It distinguishes from siblings like pause_line_item or resume_line_item by focusing on approval workflow.

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 provides clear context about when to use it ('when the approval workflow is enabled' and 'Line items in NEEDS_APPROVAL status'), but doesn't explicitly state when NOT to use it or mention specific alternatives among the many sibling tools.

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