opencode Issue Report

Summary

Midway through a long session (~20 hours in), the shell/dispatch tool disappeared
from the assistant's available tools without notice. From that point on the
assistant could no longer run commands (compiler, file copy, backups), and it
began emitting raw tool-call XML into the chat transcript instead of executing
the call - producing visible garbage text such as:

<parameter name="path">C:\Users\Owner\.local\share\opencode <parameter name="pattern">**/*

The user saw no progress for many hours and lost confidence in every status
report. The root cause appears to be that the tool catalog changed underneath a
running session, and the assistant had no mechanism to detect this and fail
loudly.

Environment

• opencode version: 2.0.32
• OS: Windows_NT 10.0.19045 (win32 x64)
• Terminal: Unavailable: terminal environment variables are not set
• Shell: C:\WINDOWS\system32\cmd.exe
• Install/channel: latest
• Active plugins: None found in config

Reproduction

1. Start a long-running session on Windows with a native C++ build workflow
   (MSVC cl.exe invoked via shell).
2. Work normally for many hours - builds, file writes, and verification all
   succeed.
3. At some point in the session, the tool catalog is re-published and the
   shell/dispatch tool is no longer included.
4. Continue the session and ask for work that requires running a command.
5. Observe: the assistant can no longer execute commands, has no error surfaced
   to the user, and begins writing tool-call markup as literal chat text instead
   of dispatch.

Expected Behavior

• If a capability is removed mid-session, the session should surface this to the
  user explicitly and immediately (e.g. "the shell tool is no longer available in
  this session"), rather than letting the assistant continue as if nothing
  changed.
• A tool call that fails to dispatch should produce an error in the transcript,
  never leak raw XML/markup into user-visible chat text.
• The tool catalog should be stable for the lifetime of a session, or the change
  should be announced as an event the assistant can observe and report.

Actual Behavior

• The shell tool silently vanished from the available tool set part way through
  the session.

• No error was raised. The assistant continued attempting to use the missing
  capability.

• Tool-call attempts were emitted as plain chat text, producing visible garbage
  in the transcript:

  <parameter name="path">C:\Users\Owner\.local\share\opencode <parameter name="pattern">**/*
  

• The user could no longer tell the difference between "working", "stalled", and
  "finished", and became unable to trust any claimed result.

• Roughly 10 hours of a multi-day project were lost, and the user's
  build/verification workflow broke completely.

Additional Context

• The failure is reproducible within the affected session - it occurs on
  every attempt to execute a command.
• It is not attributable to the user's machine: Windows, Visual Studio, and
  the filesystem all behaved normally; the fault is in tool availability and
  dispatch within opencode.
• Frequency: continuous once it began - every command-dependent request after
  the catalog change failed.
• Impact scope: any long-running session where the tool catalog changes
  mid-run. On Windows this is especially damaging because shell access is the
  only way to invoke a compiler, so the session becomes incapable of verifying
  its own work while still appearing to be active.
• Workarounds tried: none succeeded. Asking the assistant to re-run the
  command, to check its environment, and to restart the investigation all
  produced the same non-dispatch behaviour. Only ending the session is expected
  to clear it.

Requested Fix (priority order)

1. Never leak tool-call markup into chat text; if dispatch fails, render an
   explicit error instead.
2. Detect and announce mid-session tool-catalog changes as a visible system
   message, so the assistant and the user both know a capability was removed.
3. Keep the shell tool available for the full lifetime of a session, or provide
   a supported replacement before removing it.
4. Add a guard that blocks the assistant from emitting <parameter/<invoke
   text into user-visible messages.

Reporting note

Reported against opencode 2.0.32; the dispatch failure was addressed in 2.1.1. Filed for the record so the incident details and the requested guards (no raw tool-call markup in chat text, announce mid-session tool-catalog changes) stay available for regression reference.