harness-exchange 0.1.0

Exchange agent/chat sessions between codex, opencode, and claude-code

harness-exchange

Exchange sessions between codex, opencode, and claude-code.

Rate-limited on one tool but still have context you need? Port your session to another harness and keep going.

harness-exchange --from codex --to opencode

Installation

pip install harness-exchange

Requires Python 3.11+.

Usage

Interactive (arrow-key selection)

harness-exchange --from codex --to opencode

Lists the 15 most recent sessions from the source harness, each with a preview of the first and last message. Use arrow keys to select, Enter to transfer.

Non-interactive (session ID)

harness-exchange --from claude --to codex --session-id <session-uuid>

Combine with --non-interactive for scripting:

harness-exchange --from codex --to opencode --session-id <id> --non-interactive

All combinations

From	To
codex	opencode
codex	claude
opencode	codex
opencode	claude
claude	codex
claude	opencode

Options

Flag	Description
--from	Source harness (codex, opencode, claude)
--to	Target harness (codex, opencode, claude)
--session-id	Transfer a specific session by ID (skips selection)
--limit	Number of recent sessions to show (default: 15)
--non-interactive	Skip interactive prompts (requires --session-id)

Storage locations

Each tool stores sessions in a different format:

Tool	Format	Location
codex	JSONL rollouts	~/.codex/sessions/YYYY/MM/DD/*.jsonl
opencode	SQLite	~/.local/share/opencode/opencode.db
claude-code	JSONL transcript	~/.claude/projects/<cwd>/<sessionId>.jsonl (+ sessions/<pid>.json and history.jsonl)

The tool detects these paths automatically (uses $HOME). Writing to opencode uses opencode's own import command so the schema stays valid; writing to claude-code produces a real projects/ transcript so the session is resumable with claude --resume.

What gets transferred

• All conversation messages, with user and assistant roles preserved
• Tool calls and their outputs (where the target format supports them)
• Session title, working directory (cwd), and timestamps
• Agent and model information (where available)

Codex injects system prompts and context (AGENTS.md, <environment_context>, permissions/personality specs) as hidden turns; these are filtered out so only the real conversation is carried over.

How it works

1. Lists the most recent sessions from the source harness (default: 15)
2. Shows a preview of the first and last real user message for each session
3. Reads the full session (metadata + all messages) from source storage
4. Writes the session into the target harness's storage format

The interactive selector uses questionary with a plain-text fallback if the library isn't available.

Development

git clone https://github.com/cnmoro/harness-exchange.git
cd harness-exchange

# Install dev dependencies
pip install -e ".[dev]"

# Run tests
pytest

License

MIT