duckduckgo_serp: GET /

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

No annotations are provided, so the description carries the full disclosure burden. It discloses the nature of the operation ('Fetches ... SERPs'), the return payload (organic results, ads, Search Assist AI answer), and critical pagination behavior (nextPageToken is pre-signed, session-bound, must be used as-is, cannot be constructed). This goes beyond a basic GET. However, it does not mention rate limits, cost, or auth requirements, which are common for SERP APIs, so it is not a 5.

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 compact and well-structured. The first sentence nails the purpose, the next expands on functionality and return types, and the final sentence lists use cases. It is slightly longer than necessary but every sentence adds value. No fluff or redundancy.

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 7-parameter tool with no output schema and no annotations, the description provides enough for an agent to call it correctly: it explains the parameter combinations (kl vs cc+setLang, precedence), pagination mechanics, and what the response includes. It lacks error-handling details and rate-limit guidance, but these are not essential for a basic call. Completeness is above average.

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 covers 100% of parameters with detailed descriptions, including the precedence rule ('Ignored if kl is set') and the required/exclusive nature of q vs nextPageToken. The description repeats some of this (region targeting with kl or cc+setLang, pagination) but does not add substantive new meaning beyond the schema. Baseline 3 is appropriate since the schema does the heavy lifting.

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 opens with 'Get DuckDuckGo Search Results' — a specific verb and resource — and then elaborates on fetching SERPs with region targeting, safesearch, device type, and pagination. It also lists the return content (organic results, ads, Search Assist AI) and explicit use cases (SEO rank tracking, SERP monitoring, visibility audits), making the tool's purpose unambiguous and differentiating it from generic search tools.

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 states when to use this tool: 'Use for SEO rank tracking, SERP feature monitoring, DuckDuckGo-specific visibility audits, and training/eval data for search agents.' It provides clear contexts but does not mention when NOT to use it or any alternative tools (though there are no siblings). This is adequate guidance for an agent.

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