# MEI bridge (protocol lives in mei-studio)

agent-mei opens **MEI** (Machine Educated Intelligence) artifacts authored in MeiStudio.
The shared wire is implemented in mei-studio (Rust **1.94.1** — do **not** bump this editor’s toolchain to chase it):

- Protocol crate: `mei-studio/crates/agent-mei-bridge`
- Docs: `mei-studio/docs/agent-mei.md`
- **Exact Mac patch steps:** `mei-studio/docs/agent-mei-mac-patch.md`

## Landed in this tree (source)

1. `crates/agent_mei_panel/src/agent_mei_panel.rs` — `control_dispatch`: `"mei_open"`; `"open"` routes `.mei.json` / `.mei` to it.
2. `crates/agent_mei_panel/src/mei_panel.rs` — GPUI `MeiReceiptPanel` over `mei.panel/v1` (tier, joules, measured_vs_modelled, merkle, jcr1_rows + grant toast).
3. `crates/zed/src/zed.rs` — dock loads `MeiReceiptPanel`.
4. `crates/joule_core/src/control.rs` — MCP tool `agent_mei_mei_open`.
5. `crates/joule_core/src/cascade_gate.rs` — MEI grant alignment note (no auto-export / no auto-ACP).

Shells PATH binary **`mei-open`** (prefer binary over path-dep — toolchain split). No network / no phone-home.

## Headless today (works without GPUI)

```bash
mei-open path/to/graph.mei.json              # validate + handle JSON
mei-open path/to/graph.mei.json --panel      # mei.panel/v1 for the dock
mei-open path/to/graph.mei.json --grant-env  # → JOULE_CODE_GRANT=l0,l1,l2,l3[,l4]
```

Naked L4 is refused unless the artifact’s `grant_capabilities` contains `l4_frontier`
(aligned with omitting `l4` from `JOULE_CODE_GRANT` / JCR-1 cascade gate).

## Smoke (Mac, after `mei-open` on PATH)

```bash
export JOULE_CODE_CONTROL_SOCK=/tmp/jc-mei.sock
export JOULE_CODE_GRANT=l0,l1,l2,l3    # no l4
agent-mei /path/to/project &
agent-mei --jc-control mei_open --jc-params '{"path":"/path/to/examples/demo.mei.json"}'
agent-mei --jc-control state
```