set_emote_parameter

Instructions

Implementation Reference

• packages/mcp-server/src/server.ts:448-484 (registration)

  Registration of the 'set_emote_parameter' tool, including Zod input schema for 'value' (number or string) and the handler function that parses the value to number and delegates to avatarTools.setParameter('VRCEmote', ...) with context.

  // Register avatar parameter tools
  server.tool(
    'set_emote_parameter',
    'Set VRCEmote on the current avatar.',
    {
      value: z.union([z.number(),z.string()]).describe('Value to set')
    },
    async ({value }, extra) => {
      try {
        const ctx = createToolContext(extra);
        
       // 文字列が数値として解析可能な場合は数値に変換
       let value_con: number;
       if (typeof value === 'string') {
         // 数値として解析を試みる
         value_con = Number(value);
         // 変換できなかった場合（NaNの場合）はエラーを投げる
         if (isNaN(value_con)) {
           throw new Error(`文字列 "${value}" を数値に変換できませんでした`);
         }
       } else {
         value_con = value;
       }
        
        const result = await avatarTools.setParameter('VRCEmote', value_con, ctx);
        return { content: [{ type: 'text', text: result }] };
      } catch (error) {
        return { 
          content: [{ 
            type: 'text', 
            text: `Error setting parameter: ${error instanceof Error ? error.message : String(error)}` 
          }],
          isError: true
        };
      }
    }
  );

• packages/mcp-server/src/tools/avatarTools.ts:351-423 (handler)

  Core handler logic for setting avatar parameters (including VRCEmote for set_emote_parameter). Performs validation, logging via context, up to 3 retry attempts with exponential backoff when calling wsClient.setAvatarParameter, and returns success/error messages.

  public async setParameter(
    parameterName: string,
    value: ParameterValue,
    ctx?: ToolContext
  ): Promise<string> {
    if (!parameterName) {
      const errorMsg = 'Missing parameter name';
      logger.error(errorMsg);
      if (ctx) await ctx.error(errorMsg);
      return errorMsg;
    }
    
    // // Validate value type
    // if (typeof value !== 'number' && typeof value !== 'boolean') {
    //   const errorMsg = `Invalid parameter value type: ${typeof value} (must be number or boolean)`;
    //   logger.error(errorMsg);
    //   if (ctx) await ctx.error(errorMsg);
    //   return errorMsg;
    // }
    
    if (ctx) {
      await ctx.info(`Setting avatar parameter ${parameterName} to ${value}`);
    }
    
    try {
      // Multiple retry attempts
      let attempts = 0;
      const maxAttempts = 3;
      
      while (attempts < maxAttempts) {
        attempts++;
        logger.info(`Setting parameter ${parameterName}=${value} (attempt ${attempts}/${maxAttempts})`);
        
        try {
          // Set parameter with timeout
          const success = await this.wsClient.setAvatarParameter(parameterName, value);
          
          if (success) {
            const successMsg = `Successfully set ${parameterName} to ${value}`;
            logger.info(successMsg);
            return successMsg;
          } else {
            logger.warn(`Failed to set parameter ${parameterName} (attempt ${attempts})`);
            
            // Try again if we have attempts left
            if (attempts < maxAttempts) {
              const delay = 300 * attempts; // Increasing delay for each retry
              logger.info(`Retrying in ${delay}ms...`);
              await new Promise(resolve => setTimeout(resolve, delay));
            }
          }
        } catch (error) {
          logger.warn(`Error setting parameter ${parameterName} (attempt ${attempts}): ${error instanceof Error ? error.message : String(error)}`);
          
          // Try again if we have attempts left
          if (attempts < maxAttempts) {
            const delay = 300 * attempts; // Increasing delay for each retry
            logger.info(`Retrying in ${delay}ms...`);
            await new Promise(resolve => setTimeout(resolve, delay));
          }
        }
      }
      
      // All attempts failed
      const failMsg = `Failed to set ${parameterName} after ${maxAttempts} attempts`;
      logger.error(failMsg);
      return failMsg;
    } catch (error) {
      const errorMsg = `Error setting parameter ${parameterName}: ${error instanceof Error ? error.message : String(error)}`;
      logger.error(errorMsg);
      return errorMsg;
    }
  }

• packages/mcp-server/src/tools/avatarTools.ts:256-256 (helper)

  Reference to 'VRCEmote' parameter in fallback list of common VRChat avatar parameters.

  'VRCEmote',