mcp-after-effects

Instructions

Implementation Reference

• src/index.ts:817-867 (handler)

  The complete registration and handler implementation for the 'mcp_aftereffects_applyEffectTemplate' MCP tool. It defines the input schema, registers the tool, and provides the handler logic that queues an 'applyEffectTemplate' command for the After Effects bridge script, waits for processing, reads results from a temporary file, and returns them to the MCP client.

  server.tool(
    "mcp_aftereffects_applyEffectTemplate",
    "Apply a predefined effect template to a layer in After Effects",
    {
      compIndex: z.number().int().positive().describe("1-based index of the target composition in the project panel."),
      layerIndex: z.number().int().positive().describe("1-based index of the target layer within the composition."),
      templateName: z.enum([
        "gaussian-blur", 
        "directional-blur", 
        "color-balance", 
        "brightness-contrast",
        "curves",
        "glow",
        "drop-shadow",
        "cinematic-look",
        "text-pop"
      ]).describe("Name of the effect template to apply."),
      customSettings: z.record(z.any()).optional().describe("Optional custom settings to override defaults.")
    },
    async (parameters) => {
      try {
        // Queue the command for After Effects
        writeCommandFile("applyEffectTemplate", parameters);
        
        // Wait a bit for After Effects to process the command
        await new Promise(resolve => setTimeout(resolve, 1000));
        
        // Get the results
        const result = readResultsFromTempFile();
        
        return {
          content: [
            {
              type: "text",
              text: result
            }
          ]
        };
      } catch (error) {
        return {
          content: [
            {
              type: "text",
              text: `Error applying effect template: ${String(error)}`
            }
          ],
          isError: true
        };
      }
    }
  );

• src/index.ts:156-170 (helper)

  Helper function used by the tool handler to write the command ('applyEffectTemplate') and parameters to a temporary JSON file ('ae_command.json') in the system temp directory, which is monitored by the After Effects MCP Bridge Auto panel.

  function writeCommandFile(command: string, args: Record<string, any> = {}): void {
    try {
      const commandFile = path.join(process.env.TEMP || process.env.TMP || '', 'ae_command.json');
      const commandData = {
        command,
        args,
        timestamp: new Date().toISOString(),
        status: "pending"  // pending, running, completed, error
      };
      fs.writeFileSync(commandFile, JSON.stringify(commandData, null, 2));
      console.error(`Command "${command}" written to ${commandFile}`);
    } catch (error) {
      console.error("Error writing command file:", error);
    }
  }

• src/index.ts:87-123 (helper)

  Helper function used by the tool handler to read the results from the After Effects temp result file ('ae_mcp_result.json'), including staleness checks and warnings.

  function readResultsFromTempFile(): string {
    try {
      const tempFilePath = path.join(process.env.TEMP || process.env.TMP || '', 'ae_mcp_result.json');
      
      // Add debugging info
      console.error(`Checking for results at: ${tempFilePath}`);
      
      if (fs.existsSync(tempFilePath)) {
        // Get file stats to check modification time
        const stats = fs.statSync(tempFilePath);
        console.error(`Result file exists, last modified: ${stats.mtime.toISOString()}`);
        
        const content = fs.readFileSync(tempFilePath, 'utf8');
        console.error(`Result file content length: ${content.length} bytes`);
        
        // If the result file is older than 30 seconds, warn the user
        const thirtySecondsAgo = new Date(Date.now() - 30 * 1000);
        if (stats.mtime < thirtySecondsAgo) {
          console.error(`WARNING: Result file is older than 30 seconds. After Effects may not be updating results.`);
          return JSON.stringify({ 
            warning: "Result file appears to be stale (not recently updated).",
            message: "This could indicate After Effects is not properly writing results or the MCP Bridge Auto panel isn't running.",
            lastModified: stats.mtime.toISOString(),
            originalContent: content
          });
        }
        
        return content;
      } else {
        console.error(`Result file not found at: ${tempFilePath}`);
        return JSON.stringify({ error: "No results file found. Please run a script in After Effects first." });
      }
    } catch (error) {
      console.error("Error reading results file:", error);
      return JSON.stringify({ error: `Failed to read results: ${String(error)}` });
    }
  }