video_search

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 adds useful behavioral context by stating 'No API key' and identifying the DDGS/DuckDuckGo video backend, which tells the agent that no authentication setup is needed. However, it does not disclose rate limits, error behavior, or whether results are live vs cached. The read-only nature of search is reasonably inferred.

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: a two-sentence overview followed by a clean Args list. Every line adds value, and the key constraint ('No API key') is front-loaded. There is no filler or repetition of schema defaults.

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 five-parameter search tool with an output schema and zero schema-level descriptions, the description covers all invocation essentials: parameter meanings, ranges, allowed values, and auth-free access. It does not discuss rate limits or when to prefer sibling tools, but the core instructions for correct invocation are 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 0%, and the description fully compensates by explaining all five parameters. It includes critical constraints and examples: max_results range (1-25), region formats ('us-en', 'wt-wt'), backend choices ('auto' or 'duckduckgo'), and snippet_chars semantics (max description length, 0 = none). This is far more informative than the bare schema titles and defaults.

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 starts with 'Video search via DDGS (DuckDuckGo video backend)', a specific verb and resource that clearly identifies the tool as a video-focused search utility. This distinguishes it from siblings like image_search, web_search, and news_search without needing to inspect their schemas.

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 gives no explicit guidance on when to use this tool versus alternatives. It does not mention exclusions, such as 'use web_search for general web queries' or 'use image_search for images'. The tool name and first line imply it is for videos, but the conditional context for choosing it over siblings is absent.

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