google_lens

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 supported input formats (URLs, file paths, base64) and the tool's general purpose. However, it omits behavioral details like rate limits, authentication, error handling, or what happens when no match is found.

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 yet informative: a clear opening sentence, context for text-only models, sample prompts, and a parameter description. Each sentence adds value, and the structure is easy to scan.

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 simplicity (one parameter) and the presence of an output schema, the description is fairly complete. It covers input formats and usage scenarios. However, it could briefly mention the return value or typical result structure to be fully self-contained.

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 only parameter, 'image_source', is clearly described as accepting 'a public image URL, local file path, or base64-encoded image data.' Since the input schema lacks a description field (0% coverage), the description adds all necessary meaning and fully explains the parameter's acceptable values.

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's action: 'Reverse image search using Google Lens.' It lists specific identification capabilities (objects, products, brands, landmarks, text) which distinguishes it from generic search tools. However, it does not explicitly differentiate it from similar sibling tools like 'google_images' or 'ocr_image'.

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 sample prompts that trigger the tool, offering clear contextual guidance on when to use it. It also explains that it gives vision capabilities to text-only models. However, it does not state when not to use it or mention alternatives among sibling tools.

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