Search YouTube Videos

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

Annotations already indicate a read-only, idempotent, open-world operation. The description adds behavioral details beyond that: the specific output fields returned and the default relevance sort order. This gives the agent a clearer picture of what to expect, though it doesn't cover pagination or error handling.

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 three short sentences, each earning its place: the search action, the returned data fields, and the sort order. It is front-loaded with the primary purpose and contains no redundant or vague phrasing.

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 simplicity of the tool (two params, no output schema, read-only annotations), the description covers the key aspects: what it searches, what it returns, and how results are ordered. It doesn't explicitly discuss edge cases like empty results or API limitations, but the annotations and schema fill in the safety profile and parameter constraints. A small gap is the lack of alternative guidance, but that's more relevant to usage guidelines.

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 has 100% coverage with descriptions for both 'query' and 'limit', so the baseline is 3. The description mentions 'keyword or phrase' which aligns with the query parameter but doesn't add additional parameter-specific detail beyond the schema. It doesn't explain the effect of the limit parameter beyond the schema's own description.

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 action ('Search YouTube'), the resource ('videos'), and the method ('by keyword or phrase'). It also enumerates the returned fields (IDs, titles, durations, channels, view counts, URLs), making it distinct from sibling tools like search_channels.

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 clear context for when to use this tool: to find YouTube videos via keywords. It doesn't explicitly mention alternatives or exclusions, but the purpose is unambiguous, and sibling tool names (e.g., search_channels, get_video_info) imply the distinctions. The lack of explicit 'use this instead of...' prevents a 5.

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