acpx: apply_patch stuck in pending state after long conversations #22222

Description

When using opencode via acpx in non-interactive (background) mode, after a session accumulates significant context (multiple rounds of continuation), apply_patch gets stuck in "pending" state indefinitely. The agent continues thinking and reading files but never actually writes anything.

Environment

• opencode-ai: 1.4.3
• acpx: 0.5.3
• OS: Linux (container)
• Model: gptloadopenai/glm (via ccload provider)
• Mode: acpx non-interactive with --approve-all

Steps to Reproduce

1. Create an acpx session: acpx --approve-all opencode -s mysession "task"
2. Let the agent work for multiple rounds, accumulating context
3. Continue the session with acpx --approve-all opencode -s mysession "continue"
4. After 3-5 continuations, apply_patch starts showing "pending" but never completes
5. Agent keeps thinking and reading but never writes files

Expected Behavior

apply_patch should complete and write files regardless of session length.

Actual Behavior

apply_patch stays pending forever. Only workaround is to kill the session and create a new one.

Related Issues

• JetBrains ACP on Windows apply_patch hang even though the file write succeeds #16371
• always stuck at “Preparing write...” #11112
• write/edit freezes when writing long content ("Preparing write..." hangs) #20477