openclaw - 💡(How to fix) Fix Large attachments silently dropped when agent session is cold/expired [1 participants]

When a user sends a message with large attachments (e.g. multiple video files, ~200MB total) to an agent that does not have an active session, the message is silently dropped. The agent never receives the message and no error is surfaced to the sender. 3. Observe: the agent does not respond and no error is shown

• If the payload is too large to process, an error should be surfaced to the sender (e.g. a reply saying the message could not be processed)
• No error is shown to the sender

TL;DR

Sending a short text-only message to wake the session before sending large attachments is a reliable workaround to prevent messages from being silently dropped.

Guidance

• Verify that the contextPruning.mode is set to cache-ttl and the ttl is set to 1h to ensure the session is being properly pruned after an hour of inactivity.
• Test sending large attachments to an agent with an active session to confirm the issue is specific to cold sessions.
• Use the sessions_send endpoint to manually poke the session and verify it can be successfully woken up.
• Consider increasing the ttl value or adjusting the contextPruning.mode to see if it affects the behavior of large attachment handling during session creation.

Example

No code snippet is provided as the issue does not require a specific code change, but rather a workaround or configuration adjustment.

Notes

The root cause of the issue is unclear, but it appears to be related to the handling of large attachments during session creation. The provided workaround is reliable, but a more permanent solution may require further investigation into the OpenClaw version or Discord API limitations.

Recommendation

Apply the workaround of sending a short text-only message to wake the session before sending large attachments, as it is a reliable and straightforward solution to prevent messages from being silently dropped.