MCP Server Adds Persistent Memory with Retrieval Scoring to Claude Code

Solving Claude Code's Memory Problem

The developer identified that Claude Code's biggest limitation as an autonomous agent isn't prompting or tool use—it's memory. While CLAUDE.md and /memory help within a project, they don't solve cross-session or cross-project memory issues. Knowledge gained in project A isn't available in project B.

Core Insight: Not All Memories Are Equal

The system implements retrieval scoring where:

• Facts that lead to successful outcomes score up
• Facts that lead to failures score down
• Stale facts that haven't been accessed decay naturally
• No manual curation needed—scoring is automatic

In practice, about 80% of stored facts are never retrieved again, with the scoring system surfacing the 20% that actually matter.

Drift Detection for Knowledge Decay

The system addresses knowledge decay where agents confidently use outdated information. Drift detection flags facts likely outdated based on age and domain volatility. Different types of information have different decay rates:

• API endpoints go stale in days
• Design decisions remain valid for months
• Config values decay faster than architectural decisions

Setup and Implementation

The solution is implemented as an MCP server. Setup takes about 30 seconds:

npx engram-mcp

Once added to Claude Code config, Claude Code can store facts, retrieve scored results, and check for drift through normal MCP tool calls.

Pricing and Availability

The free tier provides 1 agent with 10,000 facts. The pro version costs $29/month for unlimited usage. The npm package is engram-mcp, and the site is engram.cipherbuilds.ai.