Source: https://reclaimllm.com/news/session-export-via-s3-presigned-url
← Back to News update Mar 19, 2026Session Export Delivery via S3 Presigned URL
We’ve upgraded our session export process to handle larger datasets by moving from direct email attachments to secure, time-limited S3 download links.Overview
RCLM users can now export their entire session history, including full metadata and raw S3 blobs, regardless of the total size. Previously, exports were sent as direct email attachments, which were capped at 40MB by AWS SES limits. We’ve transitioned to a more robust delivery method using secure, presigned S3 URLs.How it Works
When you request a session export, RCLM now performs the following steps in the background:- Asynchronous Processing: The export starts immediately as a background task, allowing you to continue using the application.
- ZIP Assembly: All your captured LLM sessions and their associated data are gathered into a single ZIP archive.
- Secure Storage: The ZIP archive is uploaded to a dedicated, private section of our S3 storage.
- Presigned URL Generation: A unique, cryptographically signed download link is generated for your specific export.
- Email Notification: You receive an email containing this secure link rather than a bulky attachment.
Why We Made This Change
As our users’ session histories grew, we encountered a hard technical limit. Direct email attachments through AWS SES are restricted to 40MB. For active users, a full export of their LLM interactions frequently exceeded 60MB, causing export failures and “HTTP content length exceeded” errors. By moving to S3-based delivery, we’ve eliminated this size ceiling. This approach is not only more reliable for large datasets but also more efficient, as it avoids the overhead of processing large MIME attachments through email servers.Current Limitations and Feedback
While this update solves the immediate size issue, there are a few things to keep in mind:- 24-Hour Expiration: Ensure you download your export within a day of receiving the email.
- Direct Link Access: Anyone with the link can download the ZIP during the 24-hour window. We send these links only to your verified account email to minimize risk.
- Memory Usage: For extremely large session counts, the export process currently assembles the entire ZIP in memory. We are monitoring performance and may move to a streaming upload model if needed.