get_channel_permissions

Retrieve all permission overwrites for a Discord channel to manage access controls and role-based permissions within a server.

Instructions

Get all permission overwrites for a channel

Input Schema

TableJSON Schema

Name	Required	Description	Default
`guildId`	Yes	The ID of the server (guild)
`channelId`	Yes	The ID of the channel

Implementation Reference

src/tools/permission-tools.ts:16-61 (handler)

The handler function that implements the core logic of fetching channel permission overwrites, resolving names for roles/members, and returning formatted JSON.

async ({ guildId, channelId }) => {
  const result = await withErrorHandling(async () => {
    const client = await getDiscordClient();
    const guild = await client.guilds.fetch(guildId);
    const channel = await guild.channels.fetch(channelId);
    if (!channel) throw new Error('Channel not found');

    const overwrites = (channel as GuildChannel).permissionOverwrites.cache.map((overwrite) => ({
      id: overwrite.id,
      type: overwrite.type === OverwriteType.Role ? 'role' : 'member',
      allow: overwrite.allow.toArray(),
      deny: overwrite.deny.toArray(),
    }));

    // Get role/member names for context
    const resolvedOverwrites = await Promise.all(
      overwrites.map(async (ow) => {
        let name = 'Unknown';
        if (ow.type === 'role') {
          const role = await guild.roles.fetch(ow.id);
          name = role?.name ?? 'Unknown Role';
        } else {
          try {
            const member = await guild.members.fetch(ow.id);
            name = member.displayName;
          } catch {
            name = 'Unknown Member';
          }
        }
        return { ...ow, name };
      })
    );

    return {
      channelId,
      channelName: channel.name,
      overwrites: resolvedOverwrites,
    };
  });

  if (!result.success) {
    return { content: [{ type: 'text', text: result.error }], isError: true };
  }

  return { content: [{ type: 'text', text: JSON.stringify(result.data, null, 2) }] };
}

src/tools/permission-tools.ts:12-15 (schema)

Input schema using Zod for validating guildId and channelId parameters.

{
  guildId: z.string().describe('The ID of the server (guild)'),
  channelId: z.string().describe('The ID of the channel'),
},

src/tools/permission-tools.ts:9-62 (registration)

Registration of the 'get_channel_permissions' tool on the MCP server, including name, description, schema, and handler.

server.tool(
  'get_channel_permissions',
  'Get all permission overwrites for a channel',
  {
    guildId: z.string().describe('The ID of the server (guild)'),
    channelId: z.string().describe('The ID of the channel'),
  },
  async ({ guildId, channelId }) => {
    const result = await withErrorHandling(async () => {
      const client = await getDiscordClient();
      const guild = await client.guilds.fetch(guildId);
      const channel = await guild.channels.fetch(channelId);
      if (!channel) throw new Error('Channel not found');

      const overwrites = (channel as GuildChannel).permissionOverwrites.cache.map((overwrite) => ({
        id: overwrite.id,
        type: overwrite.type === OverwriteType.Role ? 'role' : 'member',
        allow: overwrite.allow.toArray(),
        deny: overwrite.deny.toArray(),
      }));

      // Get role/member names for context
      const resolvedOverwrites = await Promise.all(
        overwrites.map(async (ow) => {
          let name = 'Unknown';
          if (ow.type === 'role') {
            const role = await guild.roles.fetch(ow.id);
            name = role?.name ?? 'Unknown Role';
          } else {
            try {
              const member = await guild.members.fetch(ow.id);
              name = member.displayName;
            } catch {
              name = 'Unknown Member';
            }
          }
          return { ...ow, name };
        })
      );

      return {
        channelId,
        channelName: channel.name,
        overwrites: resolvedOverwrites,
      };
    });

    if (!result.success) {
      return { content: [{ type: 'text', text: result.error }], isError: true };
    }

    return { content: [{ type: 'text', text: JSON.stringify(result.data, null, 2) }] };
  }
);

discord-mcp