update_ad_copy

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

The description discloses that the tool 'Re-sends the full creative' automatically, which is a behind-the-scenes behavior not covered by annotations. It also mentions character limits for title and body, adding context beyond the boolean annotations.

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?

Three concise sentences front-load the purpose and usage, followed by behavioral disclosure and constraints. Every sentence adds value without 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?

The description covers core behavior, parameter usage, and constraints. It does not address return values (output schema exists) or error conditions, but for a 4-parameter tool this is fairly complete.

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, the description compensates by clarifying that optional parameters are for fields to change and providing character constraints for title and body. However, it does not describe the ad_id or target_url parameters.

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 verb 'update' and the resource 'ad's creative copy'. It distinguishes itself from siblings like 'create_ad_variant' by focusing on updating existing copy rather than creating new variants.

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 explicitly tells users to 'Pass only the fields you want to change', indicating partial updates. It also provides character limits and best practice advice, though it does not explicitly state when to avoid using this tool.

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