This directory owns the replay and real-model test composition for a headless coding agent: DeepSeek V4 + local bash and filesystem tools + subagent delegation + workflows and fresh-agent Ralph iteration + `todo_write` + JSONL persistence. It explicitly mounts the shared agent spine, one root agent, persistence, and checkpoint policy; it is not a second product entry point.
The product command is [`dsh --profile headless`](../../apps/cli/README.md): it accepts one nonblank task, creates and persists a fresh session, prints the final assistant text, and exits.
Snapshot suites run this directory's configuration through [`tests/fixtures/headless-driver.ts`](tests/fixtures/headless-driver.ts), an unexported test-only process that emits canonical session events as JSONL before its result record. That stream is test infrastructure, not a supported CLI output format. Child sessions surface only through parent tool events and results.
[`e2b.cordis.yml`](e2b.cordis.yml) replaces the local filesystem and subprocess providers with one shared E2B sandbox while retaining `dsh-bash-local` and the same model-facing tools. Put `E2B_API_KEY` beside `DEEPSEEK_API_KEY` in the gitignored root `.env`, then run the credential-gated live composition, which drives FS, Bash, PTY, and LSP in one sandbox and proves final deletion:
The overlay creates the same absolute cwd inside the sandbox, but it does not upload or mount the host workspace. File and Bash mutations exist only in E2B; Cordis, model calls, agent/session state, session logs, skills, and SDK buffers remain on the host. The composition kills its sandbox on timeout and disposal. It is a provider-composition POC, not a whole-harness migration or a workspace-sync feature.
