update_ad_creative

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

With no annotations provided, the description carries full transparency burden. It discloses the key limitation that content fields will likely be rejected, notes the reliability of the name field, explains the access_token fallback behavior, and provides field-specific caveats. It also clarifies how creative_features_spec should be sent (top-level field).

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 longer than ideal, with the 'NOTE: Meta API may reject this' repeated for six separate fields. However, it is well-structured with an Args list and Returns section, and the length is justified by the need to document 15 parameters and a critical API constraint. Every section earns its place, though some repetition could be consolidated.

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 (15 params, no annotations, presence of output schema), the description is complete. It covers purpose, usage boundaries, parameter semantics, and expected returns. It also references the related update_ad tool, providing necessary cross-tool context. The output schema handles return details, so the brief Returns line is sufficient.

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 description coverage is 0%, but the description documents all 15 parameters, including type guidance (e.g., 'DEGREES_OF_FREEDOM' for flex creatives, ['AUTOMATIC_FORMAT'] for flexible ads) and explicit notes on which will likely be rejected. This fully compensates for the missing 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 description clearly states the tool 'Update an existing ad creative's name or optimization settings' and explicitly contrasts with content updates. It names the resource (ad creative) and the specific allowed changes, distinguishing it from siblings like create_ad_creative and update_ad.

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 explains when to use this tool (for name/optimization settings) and when not to (for content fields), and it names the alternative workflow: create a new creative and reference it via update_ad. The 'IMPORTANT — Meta API limitation' note provides clear guidance.

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