Hollow

What's New — The Final OS Primitive

Named locks prevent concurrent corruption but don't provide atomicity. An orchestrator that modifies 3 files and spawns 2 workers has a race window: if it fails after the first write, the system is in partial state. v1.2.0 adds true atomic transactions — the last missing primitive for reliable multi-agent workflows.

agents/transaction.py — TransactionCoordinator

• begin(agent_id) — create transaction (txn_id), start 60s timeout watchdog
• stage(txn_id, op_type, params) — buffer op (NOT applied to disk/state). op_type: fs_write | memory_set | message_send
• commit(txn_id) — conflict-check → apply all-or-nothing → emit txn.committed or txn.conflict
• rollback(txn_id, reason) — discard all staged ops → emit txn.rolled_back
• Conflict detection: if any staged resource was written by another agent after txn begin → {ok: false, conflicts: [...]}
• Isolation: read-committed. Staged writes are invisible to all agents until commit.
• Timeout: watchdog auto-rolls-back open transactions after 60s. Open txns also rolled-back on server restart.
• Persistence: transactions.json survives restarts.

API

• POST /txn/begin → txn_id
• POST /txn/{id}/stage — buffer an op
• POST /txn/{id}/commit — atomic apply (409 on conflict)
• POST /txn/{id}/rollback — explicit discard
• GET /txn/{id} — status (open/committed/rolled_back, ops_count, expires_in_seconds)
• POST /fs/write — new txn_id field: stages instead of writing if set
• POST /messages — new txn_id field: stages message send instead of delivering

Events

txn.committed, txn.rolled_back, txn.conflict

New MCP Tools (4)

txn_begin, txn_commit, txn_rollback, txn_status

Total: 64 MCP tools

Integration Tests

6 tests in tests/integration/test_transactions.py — happy path 3-file atomic commit, explicit rollback, atomicity on partial failure, conflict detection, timeout auto-rollback (@pytest.mark.slow), isolation + auth enforcement.

AgentOS is Feature-Complete

| OS Primitive | Version |
|---|---|
| Identity + capability isolation | v0.6.0 |
| Resource budgets (tokens) | v0.6.0 |
| Session persistence + handoffs | v0.6.0 |
| Semantic memory (embeddings) | v0.6.0 |
| Standards injection | v0.6.0 |
| Reactive event system (interrupts) | v0.7.0 |
| Process signals + tombstones | v0.8.0 |
| VRAM-aware priority scheduler | v0.9.0 |
| Context-window memory management | v1.0.0 |
| Unified audit kernel + anomaly detection | v1.1.0 |
| Multi-agent atomic transactions | v1.2.0 ✓ |