get_ad_image

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

No annotations are provided, so the description carries the full burden. It discloses that the tool returns 'the image the ad is currently serving,' indicating the image may change over time, and mentions the optional access_token behavior ('will use cached token if not provided'). It implies a read-only operation and return format ('ready for direct visual analysis'). However, it doesn't explicitly state error handling or side effects, though for a get operation this is less critical.

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 concise and well-structured. It starts with a clear summary sentence, then provides usage context, an alternative tool reference, and a structured Args/Returns section. No redundant information; every sentence adds value.

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?

Despite having no output schema and no annotations, the description is complete for this simple tool. It explains the input parameters, the return behavior ('The ad image ready for direct visual analysis'), and provides contextual guidance on when to use an alternative tool. There are no significant gaps for the agent to make correct usage decisions.

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%, so the description must compensate. It explains both parameters in the Args section: ad_id ('Meta Ads ad ID') and access_token ('Meta API access token (optional - will use cached token if not provided)'). This adds meaningful context beyond the bare schema, especially for the token behavior.

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 identifies the tool's function: 'Get, download, and visualize the image attached to an existing Meta ad.' It uses a specific verb (get/download/visualize) and resource (existing Meta ad image). It also distinguishes itself from the sibling tool get_image_by_hash, explicitly stating 'If all you have is an image hash (no ad), use get_image_by_hash instead.'

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 explicit usage guidance, including when to use this tool (when you have a Meta ad ID) and when not to (when you only have an image hash). It names the alternative tool (get_image_by_hash), making the decision process clear for the agent.

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