Google Ad Manager MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions the tool updates properties and returns updated details, but lacks critical information such as required permissions, whether changes are reversible, rate limits, or error conditions. For a mutation tool with zero annotation coverage, this is a significant gap in 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 appropriately sized and front-loaded, starting with the core purpose followed by parameter details and a constraint. Every sentence adds value, with no redundant information. However, the structure could be slightly improved by integrating the constraint more seamlessly rather than as a separate statement.

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 complexity (a mutation with 3 parameters) and the presence of an output schema (which handles return values), the description is reasonably complete. It covers the purpose, parameters, and a key constraint. However, it lacks behavioral details like permissions or side effects, which are important for a mutation tool without annotations, preventing a perfect score.

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 adds substantial meaning beyond the input schema, which has 0% description coverage. It explains each parameter's purpose: 'creative_id: The creative ID to update,' 'destination_url: New destination/click-through URL for the creative,' and 'name: New name for the creative.' Additionally, it provides the constraint 'At least one of destination_url or name must be provided,' which is not evident from the schema alone. This fully compensates for the schema's lack of 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 description clearly states the tool's purpose: 'Update an existing creative's properties.' It specifies the verb ('update') and resource ('creative'), making the function unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'update_line_item_name' or 'upload_and_associate_creative', which also modify creative-related entities.

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 implied usage guidance by stating 'At least one of destination_url or name must be provided,' which indicates when the tool should be used (when updating those specific properties). However, it doesn't explicitly mention when to use this tool versus alternatives like 'upload_creative' for new creatives or 'get_creative' for read-only access, nor does it specify prerequisites or exclusions.

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