## Summary
- Switches sandbox filesystem file uploads from `multipart/form-data` to
`application/octet-stream` in both the JS and Python SDKs
- Each file is now uploaded as raw binary with the path passed as a
query parameter, matching the `application/octet-stream` content type in
the envd API spec
- Multi-file writes send one request per file sequentially
## Test plan
- [ ] Run JS SDK filesystem write tests (`pnpm run test` in
`packages/js-sdk`)
- [ ] Run Python SDK filesystem write tests (`pytest` in
`packages/python-sdk`)
- [ ] Verify single file write, multi-file write, and various data types
(string, bytes, streams)
🤖 Generated with [Claude Code](https://claude.com/claude-code)
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Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Mish Ushakov
cf35f61b44