ytmcp

reply_to_comment

Post a reply to a specific YouTube comment using its video ID, comment ID, and reply text, enabling automated comment moderation and engagement.

Instructions

Reply to a comment on a video.

Args: video_id: The video id the comment belongs to. comment_id: The comment to reply to. text: Reply text.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "video_id": "<video_id>",
      "comment_id": "<comment_id>",
      "text": "<text>"
    },
    "name": "reply_to_comment"
  }
}

Input Schema

Name	Required	Description	Default
`text`	Yes
`video_id`	Yes
`comment_id`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 1, 2026

TDQS

B3.1/5.0

Behavior2/5

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

No annotations are provided, so the description carries the full behavioral burden for a mutation tool. It does not disclose authentication/permission needs, whether the reply is public, rate limits, or other side effects beyond the basic action.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The purpose is front-loaded and the Args block is compact and useful. There is no filler or redundant explanation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple reply mutation with an output schema, the description covers the call mechanics and parameters. However, with no annotations, it omits important behavioral context such as permissions or visibility of the reply.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, and the description compensates by documenting all three parameters at a basic level: video_id's association, comment_id's target, and text as reply content. It lacks format or constraint details, so it is minimally adequate rather than rich.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource: reply to a comment on a video. It is clearly distinct from siblings like list_comments and moderate_comment, though it does not explicitly route the agent from those alternatives.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives no when-to-use guidance, no prerequisites, and no alternative tools to consider. Usage is only implied by the verb 'Reply'.

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