Web Search

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

Annotations already declare readOnlyHint=true, so the tool is inherently read-only. The description adds behavioral context: what each mode returns (titles/URLs/snippets vs. AI answer), default backends, and that mode can be chosen. No contradictions; description supplements annotations well.

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 extremely concise—two short sentences. It is front-loaded with the primary action and uses line breaks for readability. Every phrase adds value; no wasted words.

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 no output schema, the description adequately covers return types per mode. It mentions key parameters (mode, backend) but omits mentioning 'numResults' for web mode or 'iaskMode'/'detailLevel' for AI mode. However, since the schema provides full descriptions and the tool is simple, completeness is high but not perfect.

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 coverage is 100%, so baseline is 3. The description adds minimal parameter semantics beyond the schema, only noting the default value for 'backend'. It does not elaborate on 'numResults', 'iaskMode', or 'detailLevel', but the schema descriptions are already sufficient. Hence score 3.

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: 'Search the web.' It distinguishes two modes with specific outputs: 'mode="web" for standard DuckDuckGo results (titles, URLs, snippets)' and 'mode="ai" for AI-generated answers'. This provides a specific verb (search) and resource (web), and differentiates the major modes effectively.

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 explicitly tells when to use each mode: 'Use mode="web" for standard DuckDuckGo results' and 'Use mode="ai" for AI-generated answers'. It also provides guidance on backend selection for AI mode. With no sibling tools, no explicit when-not is necessary, but the guidance is clear and actionable.

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