search_youtube

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions that the tool 'Returns metadata list (~200 tokens),' which gives some insight into output format and size, but lacks critical details like whether this is a read-only operation, rate limits, authentication requirements, or error handling. For a search tool with no annotations, this is insufficient.

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 and front-loaded: two sentences that directly state the tool's function and output. Every word earns its place, with no redundant information or fluff. It efficiently communicates the core purpose without unnecessary elaboration.

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 tool's moderate complexity (5 parameters, no output schema, no annotations), the description is minimally adequate. It covers the basic purpose and output format but lacks details on behavioral traits, usage context, and parameter nuances. Without annotations or an output schema, the agent might struggle with full operational understanding, though the core function is clear.

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 schema description coverage is 80% (high), so the baseline score is 3. The description adds minimal value beyond the schema—it mentions 'by keyword,' which aligns with the 'query' parameter, but doesn't explain parameter interactions or provide additional context like search scope or result formatting. This meets the baseline but doesn't enhance understanding significantly.

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 YouTube videos by keyword.' It specifies the verb ('Search') and resource ('YouTube videos'), making the function unambiguous. However, it doesn't explicitly differentiate this tool from sibling tools like 'search_transcripts' or 'get_video', which could cause confusion about when to use each.

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 no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'search_transcripts' (for searching within video transcripts) or 'get_video' (for retrieving specific video details), leaving the agent to infer usage context. There are no explicit when-to-use or when-not-to-use instructions.

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