Claude Code

@db0-ai/claude-code is an MCP server that gives Claude Code persistent memory, state, and logging via 9 MCP tools. Knowledge survives across sessions — beyond what CLAUDE.md can hold.

Install

npx @db0-ai/claude-code init

This registers the MCP server in your Claude Code configuration.

Storage

By default, memories are stored at ~/.claude/db0.sqlite.

# SQLite (local file)
export DB0_STORAGE=./my-agent.db

# PostgreSQL (remote sync)
export DB0_STORAGE=postgresql://user:pass@host:5432/db

Environment variables

Variable Default Description
DB0_STORAGE ~/.claude/db0.sqlite Storage path or PostgreSQL connection string
DB0_AGENT_ID claude-code Agent identifier
DB0_USER_ID system user User identifier

MCP tools

The server exposes 9 tools to Claude Code:

Tool Description
memory_write Write a memory with scope and tags
memory_search Search memories by query
memory_list List memories with filters
memory_delete Delete a memory
state_checkpoint Save execution state
state_restore Roll back to a checkpoint
state_list List available checkpoints
log_append Log a structured event
log_query Query log entries

Skills

The plugin includes built-in skills for:

  • Memory inspection — browse and search the memory database
  • Fact ingestion — manually write specific facts into memory

Hooks

Automated workflows can be configured via Claude Code hooks to trigger memory operations on events like file changes or session start.