Convert a session between agents

This guide shows how to move a session from one agent's store into another's — a Devin session resumed by cline --id <id>, a Cline session resumed by devin -r <id>, and so on.

Conversion is a store-to-store copy through the canonical IR: read the session out of the source store, write it into the target agent's layout, and hand back the id that agent resumes with. No intermediate file, no daemon — the store verbs work straight on the stores.

The three routes

You want	Command
a session in another agent's store	sepia install <id> --from <a> --to <b>
a portable copy on disk	sepia export <id> [out] — IR JSON, or --format cline for a Cline session dir
a file from elsewhere in a store	sepia import <path> --to <b>

install is the convert verb: read → IR → write, printing the id to resume with. export + import is the same conversion split in two, for when you want to inspect or carry the copy yourself. An orchestrator gets the same operation as sessions.convert on the serve wire.

Convert a Devin session

install defaults to --from devin --to cline, so the bare form copies a Devin session into the Cline store:

sepia install roomy-relative --from devin

Name the target explicitly to land somewhere else:

sepia install roomy-relative --from devin --to claude
sepia install roomy-relative --from devin --to cursor
sepia install <id> --from cline --to devin

The Cline target says where it went and how to pick it up:

Installed session roomy-relative into /home/you/.cline/data
Resume it with: cline --id roomy-relative -m <model>

What each target writes, and how the agent resumes it:

Target	Written	Resume with
cline	<data-dir>/sessions/<id>/ (manifest + transcript) plus the index row	cline --id <id>
claude	<claude-dir>/projects/<cwd-slug>/<id>.jsonl	Claude Code's own resume over that project
cursor	<cursor-dir>/projects/<cwd-slug>/agent-transcripts/<id>/ plus chats/<hash>/<id>/	cursor-agent --resume from that project
devin	sessions, message_nodes, prompt_history rows	devin -r <id>

The Cline target also drops <id>.sepia.json next to the manifest: the IR sidecar sepia reads back from. Cline itself only loads the manifest and transcript, so the sidecar is invisible to it.

The source is only read: converting never edits the session you converted from (Devin's database is opened read-only).

Store selection and the default dirs

--from/--to name a store. --db sets where Devin's SQLite lives; the three --*-dir flags both point at a store and select it when the corresponding role is silent — which is why a single --data-dir is enough to write Cline layout into a scratch directory.

Store	Path flag	Default
devin	--db	~/.local/share/devin/cli/sessions.db
cline	--data-dir	~/.cline/data
claude	--claude-dir	~/.claude
cursor	--cursor-dir	~/.cursor

When both forms appear, the explicit --from/--to wins; the path flag only decides the role that flag left unnamed.

Convert into a scratch directory first — it costs nothing and shows exactly what would land in a real agent store:

mkdir -p /tmp/probe
sepia install roomy-relative --from devin --data-dir /tmp/probe
sepia list --data-dir /tmp/probe

Ids, collisions, --force

• --id <new-id> installs under a different id. Without it claude, cursor and devin keep the session's own id — which is what makes a converted copy answer to the same devin -r <id> — while a Cline target derives a fresh id from the session's creation time and prints the one it chose.
• claude and cursor refuse an id that already exists in the target store — pass --force to overwrite.
• A devin target leaves an existing session alone and says so (already imported; leaving it untouched); --force does not overwrite there.
• --force also lets a Cline install replace a session row a live session still owns.

What survives the trip

Everything the IR models: the node forest (branches, not a flat list), roles, text and non-text blocks, thinking with its provider signature, tool calls with arguments, status, locations and diffs, tool results with exit codes and timings, prompt history, checkpoints, and the meta overlay (title, working directory, model). Signatures are replayed verbatim so the target's model can keep using the transcript; fields a target store cannot express are marked lossy in metadata instead of dropped — see session formats.

Transcripts are copied whole, so the cost scales with the source: a 40k-node Devin session lands as roughly 540 MB of Claude JSONL and converts in seconds. Budget disk, not patience.

Agent configs are a separate install

sepia install moves sessions. Rules, skills, commands, hooks, subagents and MCP servers convert with sepia config install --from <a> --to <b> — see agent configs.

Check the result

sepia list --from claude                     # or --data-dir / --cursor-dir
sepia export roomy-relative --from claude | head -c 400

Listing it back with the right title and working directory means the target store's layout is right; export shows the IR that agent will hand back on the next read.