google_youtube_list_commentsList comment threads for a YouTube video, most recent first, with pagination and max results to review viewer feedback efficiently.
List comment threads for a video, most recent first.
| Name | Required | Description | Default |
|---|---|---|---|
| account | No | Account nickname to use. | |
| videoId | Yes | YouTube video ID. | |
| pageToken | No | Page token from a previous result's nextPageToken. | |
| maxResults | No | Max results (default 20). |
Changes observed during successful MCP inspections.
v0.1.95Input schema / properties / pageTokenAdded value: +{
+ "description": "Page token from a previous result's nextPageToken.",
+ "type": "string"
+}v0.1.60Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden and only discloses the sort order ('most recent first'). It says nothing about whether replies are nested in threads, how pagination terminates, quota/rate-limit costs of the YouTube Data API, or what happens when comments are disabled.
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?
A single front-loaded sentence with no filler. It is efficient, though its brevity leaves the behavioral gaps noted elsewhere rather than being padded.
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 list tool with full schema coverage, the description covers the core intent, but with no output schema and no annotations it should at least hint at the response shape (threads containing replies, nextPageToken) and quota implications.
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 account, videoId, pageToken, and maxResults are all already documented in the schema. The description adds nothing parameter-specific beyond implying the ordering of results; 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 (List) and resource (comment threads for a video), which clearly separates it from google_youtube_insert_comment and google_youtube_set_comment_moderation. It does not explicitly name those siblings, but the read-vs-write distinction is obvious from the verb.
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?
No guidance on when to use this versus alternatives, no prerequisites (e.g., comments must be enabled on the video, required OAuth scope), and no mention of how to continue pagination. The agent must infer all usage conditions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.