mcp-discord

discord_get_reactions

Retrieve users who reacted with a specific emoji on a Discord message, supporting pagination for handling large reaction lists.

Instructions

List users who reacted with a specific emoji on a message. Paginated (default 25, max 100).

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": {
      "channel_id": "<channel_id>",
      "message_id": "<message_id>",
      "emoji": "<emoji>"
    },
    "name": "discord_get_reactions"
  }
}

Input Schema

Name	Required	Description
`channel_id`	Yes
`message_id`	Yes
`emoji`	Yes
`limit`	No	1-100, default 25.
`after`	No	User ID cursor for pagination.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Apr 23, 2026

TDQS

A4.2/5.0

Behavior4/5

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

No annotations are provided, so the description carries the full burden. It discloses key behavioral traits: pagination support, default limit (25), and maximum limit (100), which are crucial for usage. However, it does not mention rate limits, permissions required, or error conditions, leaving some gaps in transparency.

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 description is a single, well-structured sentence that front-loads the core purpose and efficiently adds pagination details. Every word earns its place, with no redundancy or unnecessary elaboration, making it highly concise and clear.

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

Completeness4/5

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

Given no annotations, no output schema, and moderate complexity (5 parameters, 3 required), the description is fairly complete. It covers the tool's purpose, pagination behavior, and key parameter details, but lacks information on return values, error handling, or authentication needs, which could be helpful for an agent.

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

Parameters4/5

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

Schema description coverage is low (40%), with only 'limit' and 'after' having descriptions. The description adds value by clarifying that 'limit' is for pagination with a default of 25 and max of 100, which compensates for the low coverage. It does not explain 'channel_id', 'message_id', or 'emoji' beyond their names, but the tool's purpose implicitly defines their roles.

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

Purpose5/5

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

The description clearly states the verb ('List users') and resource ('who reacted with a specific emoji on a message'), making the purpose specific and unambiguous. It distinguishes from siblings like discord_add_reaction (adds reactions) and discord_remove_reaction (removes reactions) by focusing on listing users, not modifying reactions.

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

Usage Guidelines3/5

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

The description implies usage when needing to see who reacted with a particular emoji, but does not explicitly state when to use this tool versus alternatives like discord_get_message (which might include reaction data) or other listing tools. No exclusions or prerequisites are mentioned, leaving some ambiguity for the agent.

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