VRChat MCP OSC

Instructions

Implementation Reference

• packages/mcp-server/src/tools/inputTools.ts:299-326 (handler)

  The main handler function for the 'jump' tool. Sends 'Jump' input with value 1.0, waits 100ms, then releases with 0.0 via wsClient. Returns success or error messages.

  public async jump(ctx?: ToolContext): Promise<string> {
    if (ctx) {
      await ctx.info('Jumping');
    }
  
    try {
      // Send jump input
      const success = await this.wsClient.sendInput('Jump', 1.0);
      if (!success) {
        return 'Failed to jump';
      }
  
      // Short delay for button press
      await delay(100);
  
      // Release jump button
      const releaseSuccess = await this.wsClient.sendInput('Jump', 0.0);
      if (!releaseSuccess) {
        return 'Jump initiated but failed to release button';
      }
  
      return 'Jumped';
    } catch (error) {
      const errorMsg = `Error jumping: ${error instanceof Error ? error.message : String(error)}`;
      logger.error(errorMsg);
      return errorMsg;
    }
  }

• packages/mcp-server/src/server.ts:536-555 (registration)

  MCP server registration of the 'jump' tool with empty input schema. Creates ToolContext and calls inputTools.jump(ctx), handling errors.

  server.tool(
    'jump',
    'Make the avatar jump.',
    {},
    async (_, extra) => {
      try {
        const ctx = createToolContext(extra);
        const result = await inputTools.jump(ctx);
        return { content: [{ type: 'text', text: result }] };
      } catch (error) {
        return { 
          content: [{ 
            type: 'text', 
            text: `Error jumping: ${error instanceof Error ? error.message : String(error)}` 
          }],
          isError: true
        };
      }
    }
  );