Stateful memory for AI agents. Temporal awareness, error loop detection, and preventive constraints.
Vlk² gives AI agents a sense of time: what's happening now (PRESENT), what's already been tried (PAST), and what should guide future decisions (FUTURE). It runs as a single binary over MCP, backed by SQLite, and manages these temporal transitions autonomously.
The killer demo: when an agent repeats the same Rust/TS/Python/Go error 3 times, Vlk² auto-archives the loop and injects a preventive constraint so the agent stops retrying the same broken approach. But the architecture is general — the temporal state machine can track any kind of past→present→future transition across any agent framework.
error[E0277]), TypeScript/JS (TS2345, TypeError), Python (ValueError, KeyError), Go (panic: nil pointer), HTTP (503 Service Unavailable), test frameworks (expected: X, got: Y), with a timestamp-stripping fallback. When the same fingerprint appears ≥3 times, Vlk² auto-archives the loop to PAST and injects a FUTURE constraint.General memory systems (agentmemory, Hindsight, Mem0, Supermemory) store facts, preferences, and context. Vlk² does one thing they don't: detect that the same Rust compile error repeated 3 times across different files and inject a constraint so the agent stops retrying the same broken approach. It's not a replacement — it's a specialized fault-detection layer that runs alongside them.
| Capability | Vlk² | agentmemory | Hindsight | Supermemory |
|---|---|---|---|---|
| Fact/persona memory | — | ✅ 53 tools | ✅ hooks | ✅ keywords |
| Cross-language error fingerprinting | ✅ 7 strategies | — | — | — |
| Autonomous loop breaking | ✅ ≥3 repeats auto-archive | — | — | — |
| Reconsolidation on retrieval | ✅ | — | — | — |
| Token-bounded context | ✅ 8K default | — | — | — |
cd vlk-core
cargo build --release
DATABASE_URL="sqlite:vlk.db?mode=rwc" ./target/release/vlk-core
Any MCP client connects via stdin/stdout — JSON-RPC 2.0, one line per message.
| Tool | Purpose |
|---|---|
vlk_record_state | Push a log/error as a PRESENT slot for loop detection |
vlk_fetch_context | Clean context with reconsolidation + loop interception |
vlk_time_travel | Archive PRESENT → PAST and inject a FUTURE constraint |
vlk_get_history | Full timeline audit |
vlk_search_memory | Keyword search across logs and constraints |
vlk_summarize_session | State counts + token estimates |
vlk_revoke_future | Remove incorrectly learned constraints |
vlk_get_facts | Retrieved distilled patterns |
vlk_consolidation_status | Show consolidation agent state with token bar |
vlk_pin_memory | Protect a pattern from forgetting |
vlk_unpin_memory | Restore normal forgetting eligibility |
error[E...], TS TS..., Python TypeError:, Go panic:, HTTP 503, test assertion, or first-80-chars fallback[SYSTEM ANCHOR] preventive constraintmemory_contents (immutable, team-agnostic)
└── FK ──► agent_timeline (PRESENT / PAST / FUTURE / PURGED)
├── memory_metadata (temporal vectors, importance, connectivity)
└── semantic_facts (distilled patterns from errors)
└── fact_contradictions (resolution tracking)
Consolidation Agent (background tokio, 30s cycle)
SCAN → EVALUATE importance → BUDGET_CHECK → ARCHIVE low-value → FORGET stale
What's tested: the core loop detection path is verified: 3 identical Rust errors → auto-archive to PAST + FUTURE constraint injection. All 13 MCP tools respond correctly.
Not yet tested: pin/unpin with non-existent timeline_ids, token budget enforcement under load, conflict resolution.
Loop detection smoke test — sends the same Rust error[E0277] 3 times and verifies auto-archive + constraint injection:
import subprocess, json, tempfile, os, sys
db = tempfile.mktemp(suffix='.db')
proc = subprocess.Popen(['./target/release/vlk-core'],
stdin=subprocess.PIPE, stdout=subprocess.PIPE,
stderr=subprocess.DEVNULL,
env={'DATABASE_URL': f'sqlite:{db}?mode=rwc'})
def rpc(msg):
proc.stdin.write((json.dumps(msg) + '\n').encode())
proc.stdin.flush()
return json.loads(proc.stdout.readline())
# Init
rpc({'jsonrpc':'2.0','id':1,'method':'initialize','params':{
'protocolVersion':'2024-11-05','capabilities':{},
'clientInfo':{'name':'test','version':'1.0'}}})
# Send the same Rust error 3 times to trigger loop detection
error = 'error[E0277]: cannot add `str` to `str`'
for i in range(3):
r = rpc({'jsonrpc':'2.0','id':i+2,'method':'tools/call','params':{
'name':'vlk_record_state',
'arguments':{'raw_log': error, 'file_context': f'lib.rs:{i*10}'}}})
assert 'PRESENT state recorded' in r['result']['content'][0]['text']
print(f' Record {i+1}: OK')
# fetch_context triggers loop detection → auto-archive → constraint injection
r = rpc({'jsonrpc':'2.0','id':5,'method':'tools/call','params':{
'name':'vlk_fetch_context','arguments':{}}})
txt = r['result']['content'][0]['text']
assert 'E0277' in txt, 'error missing after fetch'
assert any(kw in txt for kw in ['SYSTEM ANCHOR', 'PREVENTIVE', 'CONSTRAINT']), \
'no constraint injected'
print(f' Fetch: loop archived + constraint injected')
proc.terminate(); proc.wait()
for f in (db, db + '-wal', db + '-shm'):
try:
os.remove(f)
except FileNotFoundError:
pass
print('PASS: loop detection works')
Add to Hermes, OpenCode, Claude Code, Codex, or any MCP host:
# ~/.hermes/config.yaml or equivalent
mcp_servers:
vlk2:
command: "vlk2"
env:
DATABASE_URL: "sqlite:~/.hermes/vlk/vlk.db?mode=rwc"
timeout: 30
Compatible with any MCP client. Works alongside agentmemory, Hindsight, Supermemory, or Hermes built-in memory.
Actively developed. The core loop detection and corrective memory cycle is implemented and E2E-tested. Vlk² is a specialized complement to general memory systems — not a replacement.
This listing does not have a supported local package template. Use the maintainer’s documentation for its hosted endpoint, authentication, and client-specific setup. No install command has been inferred.
https://github.com/aranajhonny/vlk/releases/download/v0.3.0/vlk-core-x86_64-unknown-linux-gnu.mcpbotherVlk MemAct works with any MCP-compatible client. Copy the config snippet from the Configuration section above and add it to the file shown for your client, then restart the application.
~/Library/Application Support/Claude/claude_desktop_config.jsonRestart Claude Desktop completely for changes to take effect.~/.cursor/mcp.jsonRestart Cursor for changes to take effect..vscode/mcp.jsonReload VS Code window for changes to take effect.~/.codeium/windsurf/mcp_config.jsonRestart Windsurf for changes to take effect..mcp.jsonSave at the project root, then start Claude Code in that project and review the MCP server approval prompt. Keep real credentials out of shared files.