Fused Web Search

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

Annotations already indicate read-only behavior (readOnlyHint: true). The description adds context about URL dedupe, cross-ranking, and key requirements, which are behaviors not fully covered by annotations. This enriches transparency beyond the annotation baseline.

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 exceptionally concise—two sentences—and well-structured. It avoids redundancy and directly conveys essential information without extraneous words, making it easy to parse.

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 schema provides some parameter descriptions and an output schema is present, the description's lack of return format or further behavioral details is acceptable. It supplies sufficient context for a search tool, but could be slightly more thorough regarding result handling or limitations.

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 description does not explain any parameter semantics. Schema coverage is only 44% (query and max_results have descriptions), leaving many parameters (layer, engines, queries, recency, complexity, exclude_domains, include_domains) undocumented. Since the description adds no parameter details, it fails to compensate for incomplete schema.

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 function: 'Multi-engine parallel search with URL dedupe and cross-ranking.' It specifies the action (search), the resource (multi-engine), and distinguishes from a built-in WebSearch, meeting the bar for specificity and differentiation.

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 explicit guidance on when to use this tool: 'Prefer over built-in WebSearch for version-sensitive facts, APIs, comparisons, and research.' It also differentiates free vs. API layers, offering clear usage context without ambiguity.

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