E2B 2.62.0 adds an output opt-out and streamed file uploads

The new retainOutput option in JavaScript, and retain_output in Python, applies to commands.run and commands.connect and defaults to true. When it is false, stdout and stderr are not buffered, so the output fields on the handle, result and exit errors are undefined or None, while output callbacks still receive all output.

files.write now streams iterables of byte chunks rather than buffering them. The JavaScript SDK accepts AsyncIterable data such as async generators and Node.js Readable streams, alongside ReadableStream. The Python SDK takes Iterable[bytes] in Sandbox and AsyncIterable[bytes] in AsyncSandbox, and each one rejects the other's kind.

Two changes break existing code. In JavaScript, ReadableStream and AsyncIterable data is no longer buffered, so browsers that cannot stream request bodies throw InvalidArgumentError and a Blob must be passed instead. Combining gzip with octet-stream uploads turned off is now rejected with an invalid-argument error in both SDKs, where gzip previously overrode the setting.

Agents that move large generated files or long command logs can avoid holding whole payloads in memory, and can skip collecting command output they never read.

Code that passes streams to JavaScript in Firefox, Safari or iOS browsers, or that pairs gzip with disabled octet-stream uploads, will now fail and needs updating before upgrading.