Retrieve the list of videos in a YouTube playlist, including public and private playlists, to enable further processing like summarizing transcripts.
List the videos in a playlist. Public playlists work with an API key; private ones need sign-in. Combine with get_transcript to summarize a whole playlist.
| Name | Required | Description | Default |
|---|---|---|---|
| playlist | Yes | Playlist ID or a URL containing ?list= | |
| page_token | No | ||
| max_results | No | 1-50 |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are present, so the description carries the full behavioral burden. It does disclose an important auth behavior (API key for public, sign-in for private) beyond the schema. However, it does not reveal that results are paginated (page_token exists) or what items the call returns beyond 'videos', leaving some operational behavior implied.
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, each earning its place: purpose first, then auth condition, then a cross-tool workflow hint. No filler, no restating of schema defaults, and the most decisive information is front-loaded.
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 3-param list tool with no annotations and no output schema, the description covers purpose, auth, and the transcript workflow, which covers the happy-path call. But pagination is unmentioned despite the page_token param being undocumented in the schema, leaving an agent to invent or miss paging behavior on long 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 coverage is 67% and the description adds essentially no parameter meaning: it does not explain playable page_token pagination or how max_results relates to page size. The 'Playlist ID or URL with ?list=' guidance already lives in the schema, so the description only adds marginal value over the structured field text.
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 opens with 'List the videos in a playlist' — a specific verb and resource that an agent can act on. This clearly distinguishes the tool from its siblings such as list_channel_uploads (channel-scoped), search_videos, and get_transcript, without needing to open any schema.
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 gives practical usage context: public playlists work with an API key while private ones need sign-in, which tells the agent the authentication precondition. It also offers a workflow hint (combine with get_transcript to summarize a playlist). It does not explicitly name alternatives or state when-not-to-use, but the condition is reasonably clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.