write_interim_draft failed for all blocks from the CEO MCP instance with
"Claude CLI failed (exit 1): unknown error". Two fixes:
1. Error surfacing (the certain win): on non-zero exit, capture and log
both stderr AND stdout (the CLI sometimes writes its diagnostic to
stdout or nowhere), so the next occurrence is diagnosable instead of
collapsing to "unknown error". This is why #85 was unsolved — the real
error was swallowed (engineering rule §6: no silent swallow).
2. Defensive hardening: strip Claude Code session markers (CLAUDECODE,
CLAUDE_CODE_*, CLAUDE_AGENT_*, AI_AGENT, CLAUDE_EFFORT) from the env of
nested `claude -p` calls and run them from $HOME, decoupling them from
the parent agent's session/project state. Aligns query() with the
existing query_streaming() path (which already sets cwd=HOME). Auth/
config vars are preserved.
Note: the original adapter-context failure could not be reproduced in a
plain interactive session (nested claude -p succeeds there in both old and
new code), so the env markers are a suspect, not a proven cause. The real
value is the diagnostics. Verified: nested query() returns PONG from
inside a CLAUDECODE=1 session; unit tests cover env sanitization.
Invariants: G1 (normalize at source — fix the spawn, not readers),
G2 (no parallel path — same query()), §6 (no silent error swallow).
INV: feedback_claude_session_local_only preserved (all calls stay local).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>