What would you like to be added?

A background memory service that runs on session startup, scans past conversation sessions, and extracts reusable project-specific skills as SKILL.md files to ~/.gemini/memory/<project>/skills/.

Key design:

• Index-based session selection — agent sees a compact listing of all sessions and uses read_file to inspect promising ones
• Sub-agent with scoped context (auto-approve, ~/.gemini/-only workspace, no shell access)
• Lock-file coordination for multi-instance safety
• Per-run state tracking with skillsCreated metadata
• Tiered confidence prompt to balance quality vs. recall
• Awareness of all existing skills (global, workspace, extension, builtin) to prevent duplication
• Gated behind experimentalMemoryManager flag

Why is this needed?

Currently, knowledge learned during a session is lost when the session ends. Users repeatedly encounter the same project-specific workflows, failure modes, and conventions across sessions, but each new session starts from scratch. This feature enables the CLI to automatically learn and remember reusable workflows, reducing repetitive discovery and improving agent efficiency over time.

Additional context

This is a single-phase approach that can evolve into a richer memory system (e.g., separating per-session extraction from global consolidation).

Sub-issue of #20062.