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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description goes beyond them by disclosing result ordering ('newest first'), the returned fields (titles, durations), and that the call is free — meaningful traits not present in the structured fields.

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?

Three short sentences, zero waste, with the core behavior and accepted inputs front-loaded before the follow-up routing hint.

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 no output schema, the description usefully states what comes back (titles and durations) and the sort order. The only minor gap is that it does not mention the default/ max limit behavior for paging through large playlists.

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%, so both parameters are already documented in the schema. The description's mention of accepted input formats ('playlist links or IDs and channel links or @handles') largely restates the url schema description, and it says nothing about the limit parameter — the 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?

States a specific verb and resource and covers both modes (playlist videos or channel uploads) with scope detail ('newest first', 'titles and durations'). An agent can immediately distinguish this from get_transcript, which the description names separately.

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?

Gives clear context ('Free') and explicitly routes the agent forward: 'Use get_transcript on the videos you need.' It does not state when-not to use it or contrast against list_languages/get_usage, but the usage intent is unambiguous.

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