Claude Code Subagent Memory Frontmatter: Persistent Per-Agent Knowledge Store Survives Across Sessions

Anthropic Claude Code Docs·high signal

Claude Code subagents now support a `memory` YAML frontmatter field with three scopes — `user` (~/.claude/agent-memory/), `project` (.claude/agent-memory/, version-controlled), and `local` (untracked). The first 200 lines of each agent's MEMORY.md are auto-injected into its system prompt at startup, and Read/Write/Edit tools are automatically enabled so the agent can self-curate its knowledge. This lets a code-reviewer subagent accumulate codebase-specific patterns, a security-auditor build its own threat model, and a test-writer remember project testing conventions — all without touching the main context window.