search_images

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes key behaviors: the search scope ('across the web'), the default return format ('small base64-encoded JPEG images'), and the alternative return option ('return image URLs, title, shapes, and other metadata'). It doesn't mention rate limits, authentication needs, or pagination behavior, but covers the essential operational characteristics.

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 appropriately sized with three sentences that each serve a distinct purpose: stating the tool's function, providing usage guidelines, and describing return behavior. It's front-loaded with the core purpose and avoids unnecessary repetition. The final sentence about default return format could be slightly more concise.

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 search tool with 6 parameters (1 required), 100% schema coverage, and no output schema, the description provides good contextual completeness. It covers the tool's purpose, usage scenarios, and key behavioral characteristics. The main gap is the lack of information about response format details beyond the base64/URL distinction, but given the schema coverage and tool complexity, this is reasonably complete.

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 100%, so the schema already documents all 6 parameters thoroughly. The description mentions the default return behavior (base64 images vs URLs) which relates to the 'return_url' parameter, but doesn't add significant semantic value beyond what's already in the schema descriptions. This meets the baseline expectation when schema coverage is complete.

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 purpose with specific verbs ('Search for images across the web') and distinguishes it from siblings by specifying it's for visual content like photos, illustrations, diagrams, etc. It explicitly mentions it's 'similar to Google Images' which provides clear context about its function.

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 guidance on when to use this tool: 'Use this when you need to find photos, illustrations, diagrams, charts, logos, or any visual content.' It gives three specific use cases: illustrating concepts, locating specific pictures, or discovering visual resources. This clearly distinguishes it from text-based search siblings like search_web or search_arxiv.

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