An agent pane inherits HOME_DIR, CLAUDE_PROJECT_DIR and LOCAL_BIN from
lib.sh's exports (and the adapters read CODEX_HOME). DiscoveryContext
prefers CLAUDE_PROJECT_DIR over the home_dir a test passes and every
adapter path reads HOME_DIR before HOME, so a suite run by an agent
wrote fake conversation folders into the user's real ~/.claude/projects
(test_adapter_discover, 40 folders on 2026-10-10).
- conftest._isolate_agent_homes (autouse): drops the four pane variables
for every test, so HOME - which the suite's tests set for an isolated
home - governs, as in a plain shell. Dropped rather than pointed into
tmp_path: a fixture-set HOME_DIR would shadow the 11 adapter-contract
tests that set HOME alone, the same way the pane's value did.
- conftest.agent_home_leak_guard (session autouse) + tests/_agent_home_guard.py:
snapshots the entry names of the real claude/agy/codex/grok/opencode/
hermes conversation directories (as the ambient environment names them,
recorded in pytest_configure) and fails on new ones; read-only. A claude
folder whose name decodes (against the file system) to a real directory
outside the temp roots is an operating agent's and is not counted.
- tests/test_issue55_agent_homes.py: the dropped-variable list is pinned
against the env reads of lib_py/agents, lib_py/paths.py and lib.sh;
guard unit tests; the issue's reproduction as a subprocess regression
(on base 42e5173 it leaves <dir>/-…-test-adapter-discover0-ws/u-c1.jsonl).
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
