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 of behavioral disclosure. It states this is a read operation ('Get') and mentions what information is returned, but doesn't cover important aspects like authentication requirements, rate limits, error handling, or whether this is a safe/idempotent operation. The description adds minimal behavioral context beyond the basic purpose.

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 perfectly concise and well-structured: a clear purpose statement followed by parameter and return value documentation in separate sections. Every sentence adds value with zero waste, making it easy to parse and understand 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?

Given the tool's simple nature (single parameter read operation) and the presence of an output schema (which handles return value documentation), the description is reasonably complete. It covers the purpose, parameter meaning, and return content at a high level. The main gap is lack of behavioral context that would be important for a production API tool.

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 explicitly documents the single parameter ('line_item_id') and its purpose, though the schema already shows it's a required integer. With 0% schema description coverage, the description compensates adequately by explaining what the parameter represents, but doesn't add format details or constraints beyond what's inferable from 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's purpose with a specific verb ('Get') and resource ('line item details by ID'), making it immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'get_order' or 'get_advertiser' beyond the resource name, which prevents a perfect score.

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 no guidance on when to use this tool versus alternatives like 'list_line_items_by_order' or 'check_line_item_delivery_status'. It mentions the required parameter but offers no context about prerequisites, error conditions, or typical use cases.

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