create_ad_creative

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

With no annotations, description carries full burden. It discloses write behavior, prerequisites (video_id, image_hash), critical constraint that image hashes are per-account, and Instagram placement condition. Lacks rate limits or error details but adequate.

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?

Five sentences, front-loaded with purpose, each sentence adds value. No redundancy, and the important note about image hashes is included without bloating.

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?

Covers the main use case and key constraints well given 13 parameters and no output schema. Could mention return value (e.g., created creative ID) but not essential for selection; the description enables correct invocation.

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?

Adds significant meaning beyond schema: explains the two data type branches (video_data vs link_data), maps specific parameters to each, clarifies conditional use of instagram_user_id, and notes image hash scope. Schema coverage is 77%, but description compensates richly.

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 it creates a single-text ad creative from an object_story_spec, distinguishes from sibling create_ad_creative_with_asset_feed, and explicitly marks it as a WRITE operation.

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?

Provides clear conditions for when to use: pass page_id plus ONE of video_data or link_data, and instagram_user_id if page not linked to Instagram. Does not explicitly exclude the asset feed sibling but the context implies this is for single-text creatives.

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