google_ads_capture_screenshot

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

No annotations are provided, so the description must fully disclose behavioral traits. It only mentions the format (PNG) and purpose, but omits details such as output handling, size limits, timeouts, or return structure (e.g., base64 data, file path). This is insufficient for a tool with no 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?

The description is a single, front-loaded sentence that efficiently conveys the main action, format, and use case. Every word adds value; there is no redundancy or verbosity.

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?

For a simple tool with one parameter and no output schema, the description covers the basic purpose and format. However, it fails to explain what the tool returns (e.g., screenshot data, success status) or any limitations (e.g., supported URL types). This leaves the agent with incomplete context.

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 input schema has 100% description coverage for the 'url' parameter. The tool description adds context about format and purpose, but does not enhance the parameter's meaning beyond what the schema already provides (URL to capture). Baseline score of 3 is appropriate.

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 action ('Capture a URL screenshot'), the output format ('PNG'), and the purpose ('for message match evaluation'). It distinguishes this tool from siblings as no other tool captures screenshots.

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 implies a use case (message match evaluation) but does not explicitly state when to use or not use this tool, nor mention alternatives. Given the absence of similar tools among siblings, the lack of explicit guidelines is a minor gap.

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