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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds value beyond them by specifying the 'public' scope constraint and disclosing a per-call cost (20포인트), which is exactly the kind of operational context annotations do not carry. It does not discuss pagination or truncation behavior.

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?

Front-loaded with the verb and payload in the first sentence, then the Korean equivalent and the cost note. The bilingual restatement is redundant for an English reader but serves the target audience and remains compact.

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?

With readOnly/openWorld annotations covering safety and no output schema, the description supplies the missing pieces: the returned fields, the public-only scope, and the cost. A complete picture for a simple 2-parameter read tool, though usage routing against siblings and any list-size limits remain unaddressed.

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 100%, and both parameters (url with list=/PL... example, count with 1~200 default 50) are fully documented in the schema. The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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?

States a specific verb and resource ('Look up a public YouTube playlist') and enumerates the return payload (title, channel, video count, video list), which clearly separates it from siblings like youtube_channel or youtube_comments. It stops short of naming any alternative tool, so sibling differentiation is implicit rather than explicit.

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?

There is no guidance on when to use this tool versus youtube_channel, youtube_search, youtube_metadata or crawl_youtube, and no stated prerequisites. The only contextual cue is 'public' playlist, which hints at a scope limit but is not framed as a usage rule.

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