code-execution-tool

 
 ### Retrieve generated files
 
-When Claude creates files during code execution, each created file's ID appears in the code execution tool result, and you can download it with the [Files API](https://platform.claude.com/docs/en/build-with-claude/files):
+When Claude saves files to its output directory during code execution (see [How generated files are captured](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool#how-generated-files-are-captured)), each file's ID appears in the code execution tool result, and you can download it with the [Files API](https://platform.claude.com/docs/en/build-with-claude/files):
 
 <CodeGroup>
   ```bash cURL

   ```
 </CodeGroup>
 
+#### How generated files are captured
+
+Each `bash_code_execution` call gets a new, empty directory, available to the command as `$OUTPUT_DIR`. When the command finishes, the files at the top level of that directory are captured and returned as the `file_id` entries in the result's `content` list. Files written anywhere else stay in the container and aren't returned.
+
+The tool description tells Claude to share files by copying them into `$OUTPUT_DIR`. If your application depends on receiving a file, prompt Claude to copy it into `$OUTPUT_DIR` and list the directory in the same command, so the `ls` output confirms the capture (Claude doesn't see the `content` list):
+
+```bash
+python /tmp/make_report.py && cp /tmp/report.pdf "$OUTPUT_DIR/" && ls "$OUTPUT_DIR"
+```
+
+A file Claude wrote elsewhere is still in the container, so you can [reuse the container](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool#container-reuse) and ask Claude to copy it into `$OUTPUT_DIR`.
+
 ## Tool definition
 
 The code execution tool requires no additional parameters:

 * `stdout`: Output from successful execution
 * `stderr`: Error messages if execution fails
 * `return_code`: 0 for success, non-zero for failure
-* `content`: A list with an entry for each file the command created. Each entry carries the `file_id` to [retrieve the file](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool#retrieve-generated-files) with the Files API
+* `content`: A list with an entry for each file the command left in `$OUTPUT_DIR` (see [How generated files are captured](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool#how-generated-files-are-captured)). Each entry carries the `file_id` to [retrieve the file](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool#retrieve-generated-files) with the Files API
 
 File operation results have their own fields: