discord_add_reaction

Add emoji reactions to Discord messages using channel ID, message ID, and emoji identifier to express responses or interactions.

Instructions

Adds an emoji reaction to a specific Discord message

Input Schema

TableJSON Schema

Name	Required	Description	Default
`channelId`	Yes
`messageId`	Yes
`emoji`	Yes

Implementation Reference

src/tools/reactions.ts:11-61 (handler)

The main execution logic for the 'discord_add_reaction' tool. Parses input args with AddReactionSchema, checks client readiness, fetches the Discord channel and message, adds the reaction using message.react(emoji), and returns a success or error response.

export async function addReactionHandler(
  args: unknown,
  context: ToolContext
): Promise<ToolResponse> {
  const { channelId, messageId, emoji } = AddReactionSchema.parse(args);
  try {
    if (!context.client.isReady()) {
      return {
        content: [{ type: 'text', text: 'Discord client not logged in.' }],
        isError: true,
      };
    }

    const channel = await context.client.channels.fetch(channelId);
    if (!(channel?.isTextBased() && 'messages' in channel)) {
      return {
        content: [
          {
            type: 'text',
            text: `Cannot find text channel with ID: ${channelId}`,
          },
        ],
        isError: true,
      };
    }

    const message = await channel.messages.fetch(messageId);
    if (!message) {
      return {
        content: [
          { type: 'text', text: `Cannot find message with ID: ${messageId}` },
        ],
        isError: true,
      };
    }

    // Add the reaction
    await message.react(emoji);

    return {
      content: [
        {
          type: 'text',
          text: `Successfully added reaction ${emoji} to message ID: ${messageId}`,
        },
      ],
    };
  } catch (error) {
    return handleDiscordError(error);
  }
}

src/tool-list.ts:174-186 (schema)

MCP protocol tool registration including the name, description, and JSON schema for input validation (channelId, messageId, emoji).

{
  name: 'discord_add_reaction',
  description: 'Adds an emoji reaction to a specific Discord message',
  inputSchema: {
    type: 'object',
    properties: {
      channelId: { type: 'string' },
      messageId: { type: 'string' },
      emoji: { type: 'string' },
    },
    required: ['channelId', 'messageId', 'emoji'],
  },
},

src/schemas.ts:73-77 (schema)
Zod runtime validation schema (AddReactionSchema) used inside the handler to parse and validate arguments.
```
export const AddReactionSchema = z.object({
  channelId: z.string(),
  messageId: z.string(),
  emoji: z.string(),
});
```

src/server.ts:161-164 (registration)

Server-side dispatch case that invokes the addReactionHandler upon receiving a 'discord_add_reaction' tool call.

case 'discord_add_reaction':
  this.logClientState('before discord_add_reaction handler');
  toolResponse = await addReactionHandler(args, this.toolContext);
  return toolResponse;

MCP-Discord