reasoning: model reasoning output stuck in infinite repetitive loop

Summary

The model reasoning/thinking output gets stuck in an infinite repetitive loop, repeating the same sentence hundreds of times within a single turn. This wastes the context window, makes the agent appear hung, and severely degrades the user experience.

Environment

• opencode version: 0.0.0-beta-18155
• install/channel: beta
• OS: Windows_NT 10.0.22631 (win32 x64)
• Terminal: TERM=xterm-256color, COLORTERM=truecolor
• Shell: C:\Windows\system32\cmd.exe
• Active plugins: @plannotator/opencode@latest, C:\Users\lonwabo.msingelwa.config\opencode\plugins\herdr-agent-state.js, C:\Users\lonwabo.msingelwa.config\opencode\plugins\planning-canvas.js, micode, superpowers@git+https://github.com/obra/superpowers.git

Reproduction

1. Engage the agent in a sustained multi-step debugging session (e.g. fixing Docker DB schema + permissions issues, ~15+ tool calls).
2. After several tool calls in the same conversation, the model's reasoning block enters a loop repeating the same sentence verbatim hundreds of times.
3. Observed loop 1: the reasoning block repeated "Let me check the entity model to get the right column types." with no progress.
4. Observed loop 2: a different turn repeated "The user is telling me to just do the work instead of narrating what I'm going to do. ..." in the same manner.
5. Both loops filled the reasoning output until the model finally emitted its actual response.

Expected Behavior

The model should produce reasoning/thinking output once per decision point, then proceed to tool calls / user-visible output without repetitive looping.

Actual Behavior

Reasoning output enters an infinite verbatim repetition, producing hundreds of identical lines in a single turn. The agent appears hung while context is consumed. The user had to intervene ("stop", "you are buggy as hell", "you are doinf this.") to prompt recovery.

Additional Context

• Frequency: twice in the same session, after a long tool-use conversation.
• Tool calls themselves completed normally — the loop is in the model's reasoning text generation, not in tool dispatch.
• The user also hit an unrelated login hang (FLUSHDB + container restart needed) in the same session, which may have compounded frustration, but the reasoning loop is independent.
• No plugin changes were made during the session; appears to be a model-generation issue under sustained multi-turn tool use.