Sessions

Pi saves conversations as sessions so you can continue work, branch from earlier turns, and revisit previous paths.

Session Storage

Sessions auto-save to ~/.pi/agent/sessions/, organized by working directory. Each session is a JSONL file with a tree structure.

pi -c                  # Continue most recent session
pi -r                  # Browse and select from past sessions
pi --no-session        # Ephemeral mode; do not save
pi --session <path|id> # Use a specific session file or partial session ID
pi --fork <path|id>    # Fork a session file or partial session ID into a new session

Use /session in interactive mode to see the current session file, session ID, message count, tokens, and cost.

For the JSONL file format and SessionManager API, see Session Format.

Session Commands

Command	Description
/resume	Browse and select previous sessions
/new	Start a new session
/name <name>	Set the current session display name
/session	Show session info
/tree	Navigate the current session tree
/fork	Create a new session from a previous user message
/clone	Duplicate the current active branch into a new session
/compact [prompt]	Summarize older context; see Compaction
/export [file]	Export session to HTML
/share	Upload as private GitHub gist with shareable HTML link

Resuming and Deleting Sessions

/resume opens an interactive session picker for the current project. pi -r opens the same picker at startup.

In the picker you can:

• search by typing
• toggle path display with Ctrl+P
• toggle sort mode with Ctrl+S
• filter to named sessions with Ctrl+N
• rename with Ctrl+R
• delete with Ctrl+D, then confirm

When available, pi uses the trash CLI for deletion instead of permanently removing files.

Naming Sessions

Use /name <name> to set a human-readable session name:

/name Refactor auth module

Named sessions are easier to find in /resume and pi -r.

Branching with /tree

Sessions are stored as trees. Every entry has an id and parentId, and the current position is the active leaf. /tree lets you jump to any previous point and continue from there without creating a new file.

Example shape:

├─ user: "Hello, can you help..."
│  └─ assistant: "Of course! I can..."
│     ├─ user: "Let's try approach A..."
│     │  └─ assistant: "For approach A..."
│     │     └─ user: "That worked..."  ← active
│     └─ user: "Actually, approach B..."
│        └─ assistant: "For approach B..."

Tree Controls

Key	Action
↑/↓	Navigate visible entries
←/→	Page up/down
Ctrl+←/Ctrl+→ or Alt+←/Alt+→	Fold/unfold or jump between branch segments
Shift+L	Set or clear a label on the selected entry
Shift+T	Toggle label timestamps
Enter	Select entry
Escape/Ctrl+C	Cancel
Ctrl+O	Cycle filter mode

Filter modes are: default, no-tools, user-only, labeled-only, and all. Configure the default with treeFilterMode in Settings.

Selection Behavior

Selecting a user or custom message:

1. Moves the leaf to the selected message's parent.
2. Places the selected message text in the editor.
3. Lets you edit and resubmit, creating a new branch.

Selecting an assistant, tool, compaction, or other non-user entry:

1. Moves the leaf to that entry.
2. Leaves the editor empty.
3. Lets you continue from that point.

Selecting the root user message resets the leaf to an empty conversation and places the original prompt in the editor.

/tree, /fork, and /clone

Feature	/tree	/fork	/clone
Output	Same session file	New session file	New session file
View	Full tree	User-message selector	Current active branch
Typical use	Explore alternatives in place	Start a new session from an earlier prompt	Duplicate current work before continuing
Summary	Optional branch summary	None	None

Use /tree when you want to keep alternatives together. Use /fork or /clone when you want a separate session file.

Branch Summaries

When /tree switches away from one branch to another, pi can summarize the abandoned branch and attach that summary at the new position. This preserves important context from the path you left without replaying the whole branch.

When prompted, choose one of:

1. no summary
2. summarize with the default prompt
3. summarize with custom focus instructions

See Compaction for branch summarization internals and extension hooks.

Session Format

Session files are JSONL and contain message entries, model changes, thinking-level changes, labels, compactions, branch summaries, and extension entries.

For parsers, extensions, SDK usage, and the full SessionManager API, see Session Format.