ROOT CAUSE (post-mortem at docs/reports/TIER2_MCP_REGRESSION_20260624.md):
- Tier 1 asserted claims from old reports without re-verifying (SSDL campaign
was designed from a static text string '6 nil-check functions' in
src/code_path_audit_gen.py:108 that was never a runtime measurement)
- Tier 2 (autonomous) made an empty fix commit (2b7e2de1) for the MCP
regression; the pre-commit hook silently stripped opencode.json +
mcp_paths.toml and the agent reported success without verifying with
'git show HEAD --stat'
- Both happened because neither tier read the critical files before acting
THE FIX (this commit):
1. .agents/agents/tier1-orchestrator.md: add MANDATORY pre-action reading
list (6 files: AGENTS.md, conductor/workflow.md, current track spec/plan,
the 3 code_styleguides). Reference the 2026-06-24 SSDL failures.
2. .agents/agents/tier2-tech-lead.md: add MANDATORY pre-action reading list
(8 files: AGENTS.md, workflow.md, edit_workflow.md, the githooks
forbidden-files.txt, the tier2_leak_prevention spec, the 3 styleguides)
+ the MANDATORY pre-commit verification gate (3 checks per commit).
3. .agents/agents/tier3-worker.md: add 4-file read list (AGENTS.md, task
spec, relevant styleguide, the actual code being modified). Tier 3 doesn't
need the full 8-file list — Tier 2's task spec is the contract.
4. .agents/agents/tier4-qa.md: same 4-file read list (analysis context).
5. conductor/tier2/agents/tier2-autonomous.md: add the 8-file MANDATORY
pre-action reading list + the MANDATORY pre-commit verification gate.
6. conductor/tier2/commands/tier-2-auto-execute.md: add the 8-file list
to the pre-flight section (step 0).
7. conductor/tier2/githooks/pre-commit: change behavior from 'silent strip
+ commit anyway' to 'strip + ABORT commit with diagnostic message'.
The previous behavior led to empty commits (the 2026-06-24 regression).
The agent MUST investigate the leak before retrying the commit.
ENFORCEMENT (all tiers):
- First commit of any track must include 'TIER-N READ <list> before <task>'
in the commit message. The failcount contract treats an unacknowledged
first commit as a red-phase failure (per the error_handling.md Rule #0
precedent).
NOT IN THIS COMMIT (deferred to followup tracks per the post-mortem):
- Rule 4 (CI gate for required files via scripts/audit_branch_required_files.py)
- AGENTS.md addition of the canonical 'MANDATORY Pre-Action Reading' section
(separate track to ensure the project-root rules reflect the same list)
- Cross-platform agent files (.opencode/, .claude/, .gemini/) — those are
generated from the canonical .agents/agents/ files; this commit updates
the canonical sources.
7 files modified, 109 insertions, 6 deletions.
Adds a tier-2 pre-commit hook that auto-unstages sandbox-only files
from any tier-2 commit, preventing the leak that hit master in
00e5a3f2 (the offender commit that was just selectively reverted
in fab2e55b). The hook is paired with a config file that lists the
forbidden paths as substring patterns.
Design:
- Hook reads conductor/tier2/githooks/forbidden-files.txt (one
substring pattern per line; # comments and blanks ignored)
- For each staged file, checks if any pattern is a substring of
the path. If a match is found, the file is auto-unstaged via
`git rm --cached --force` (force is required when the index
has content that differs from BOTH HEAD and the working tree)
- Hook always exits 0 — it removes the leak rather than blocking
the commit. A hard reject would leave tier-2 stuck mid-flow
(tier-2 cannot run `git restore --staged`, which is banned by
the sandbox permission rules)
- The hook's config file lives at the project root so it ships
with the clone. setup_tier2_clone.ps1 will install the hook
in a follow-up commit; existing clones need to re-run setup
to get the hook
Forbidden patterns (substring matches):
- .opencode/agents/tier2-autonomous (sandbox agent prompt)
- .opencode/commands/tier-2-auto-execute (sandbox slash command)
- opencode.json (MCP path / default_agent / model override)
- mcp_paths.toml (extra_dirs cleared in clone)
Patterns are SPECIFIC (not prefix-based) so they do not match
the legitimate interactive tier-2 tech-lead prompt at
.opencode/agents/tier2-tech-lead.md.
Tests (tests/test_tier2_pre_commit_hook.py, 12 cases):
- Empty staged set: git's standard "nothing to commit" error
- Allowed files: commit succeeds normally
- Each forbidden file (agent, command, opencode.json,
mcp_paths.toml) staged: auto-unstaged, commit proceeds
- Mixed staged set: only forbidden are unstaged
- Hook silent when no leaks detected
- Hook warns (stderr) when unstaging
- Config-driven: replacing forbidden-files.txt changes the
denylist without modifying the hook
- Paths with spaces: handled correctly via git diff -z
Defense-in-depth context:
- Layer 1: OpenCode permission system (denies direct edits to
these files from the tier2-autonomous agent)
- Layer 2 (this commit): pre-commit hook (removes the leak at
the commit boundary)
- Layer 3 (follow-up commit): scripts/audit_tier2_leaks.py
(scans working tree, CI gate)
ed