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Vlk MemAct

Vlk MemAct

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github.com/aranajhonnyMemory & Knowledge3Updated 17w ago

About Vlk MemAct

Vlk MemAct is a SQLite-backed temporal memory MCP server for agents, organizing memories as PRESENT, PAST, and FUTURE. It targets workflows that need to detect repeated errors and prevent agents from retrying failed approaches, alongside background consolidation and token budgeting.

Key features

  1. 01Organize memories by temporal state
  2. 02Fingerprint errors across languages
  3. 03Archive repeated errors and add constraints
  4. 04Reconcile contradictory memories on retrieval
  5. 05Consolidate and prune stale memories
  6. 06Archive low-priority content to meet token budgets

Use cases

  1. 01Stop agents from retrying a repeatedly failed fix
  2. 02Supply future sessions with context and preventive constraints
  3. 03Limit the token footprint of active memory

MCP support

As a single binary, it exposes tools for recording and retrieving memory, browsing history, searching, and checking consolidation status over MCP. Clients connect through standard input and output.

Configuration

Local server config is the same for every client. Copy it into your client’s MCP config file.

No install method listed yet

We haven’t collected a package or remote endpoint for this server. Follow the instructions in the project README.

Repository
Packages
mcpbvlk-core-x86_64-unknown-linux-gnu.mcpb

Tools

No tool list yet

Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.

Details

From the project README

Vlk² — Temporal State Machine for AI Agents

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.

What It Does

  • Temporal state machine — each memory has a state: PRESENT (active context), PAST (archived, hidden from context), FUTURE (preventive constraints), PURGED (forgotten). A background agent transitions entries between states without agent intervention.
  • Cross-language loop detection — fingerprints errors by language, not by string match. Recognizes Rust (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.
  • Reconsolidation on retrieval — every recall checks current beliefs; if contradictory, the memory rewrites itself.
  • Token budget enforcement — every 30s, estimates total tokens in PRESENT + FUTURE. If over budget (8K default), archives lowest-importance entries until under budget.
  • Autonomous consolidation — background task (30s cycle) evaluates importance, archives stale entries, and forgets disconnected ones.

Why Not Just a Memory System?

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.

CapabilityVlk²agentmemoryHindsightSupermemory
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———

Quick Start

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.

MCP Tools

ToolPurpose
vlk_record_statePush a log/error as a PRESENT slot for loop detection
vlk_fetch_contextClean context with reconsolidation + loop interception
vlk_time_travelArchive PRESENT → PAST and inject a FUTURE constraint
vlk_get_historyFull timeline audit
vlk_search_memoryKeyword search across logs and constraints
vlk_summarize_sessionState counts + token estimates
vlk_revoke_futureRemove incorrectly learned constraints
vlk_get_factsRetrieved distilled patterns
vlk_consolidation_statusShow consolidation agent state with token bar
vlk_pin_memoryProtect a pattern from forgetting
vlk_unpin_memoryRestore normal forgetting eligibility

How Loop Detection Works

  1. Each error is fingerprinted by type: Rust error[E...], TS TS..., Python TypeError:, Go panic:, HTTP 503, test assertion, or first-80-chars fallback
  2. Fingerprints group near-duplicates — same error code with different timestamps/line numbers count as one pattern
  3. At ≥3 repeats → auto-archives the loop + injects [SYSTEM ANCHOR] preventive constraint
  4. Future context fetches include the constraint, so the agent stops repeating

Architecture

memory_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

Verification

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')

Integration

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.

Requirements

  • Rust 2021 edition
  • SQLite (bundled via sqlx)
  • 6.4MB binary

Current Status

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.

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