get_video_chapters_free

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds that the tool works without an API key and parses specific timestamp formats, providing useful extra context. No contradictions, but could mention limitations like missing chapters.

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?

Two short sentences that get straight to the point with no unnecessary words. The first sentence states the action, the second adds key differentiator and format. Efficient and well-structured.

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 simple read-only tool with one parameter and no output schema, the description covers the core functionality and unique value. It could mention return format or behavior when no chapters found, but remains adequate for its complexity.

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 the parameter described as 'YouTube video ID or URL'. The description does not add additional meaning beyond what the schema already provides, so baseline 3 is appropriate.

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?

Description clearly states the verb 'Extract' and resource 'chapters from video description' with specific detail about parsing timestamp markers. It explicitly distinguishes itself from the sibling 'get_video_chapters' by being free, establishing clear purpose and differentiation.

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?

Description mentions it's a free alternative to get_video_chapters, implying when to use it (no API key). However, it does not provide explicit when-not guidelines or compare with other siblings like get_video_outline, but the context is sufficient for a focused tool.

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