> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dropbear.dreamscalelabs.com/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Treat the Dropbear Python SDK and CLI as the supported public integration surfaces.
> Prefer context-managed sessions and model-specific observation helpers.
> Do not infer or recommend internal control-plane APIs.

# Model contracts

> Match camera, state, action ordering, units, chunk size, and rate for the live Dropbear models.

A Dropbear observation is expressed in the selected model's coordinates, not
necessarily your controller's coordinates. Convert at the `RobotIO` boundary
and validate the returned model action before converting it back.

<Warning>
  Matching a vector length is not enough. Joint order, units, camera order,
  gripper convention, and absolute-versus-delta semantics must all match.
</Warning>

The production catalog currently exposes the three contracts below. Check
[Models](https://dropbear.dreamscalelabs.com/dashboard/models) before opening a
session because
availability is region- and account-dependent.

| Model              | Observation helper        | Output                                | Nominal rate |
| ------------------ | ------------------------- | ------------------------------------- | ------------ |
| `molmoact2-so101`  | `dropbear.so101.observe`  | 30 × 6 absolute joint positions       | 30 Hz        |
| `molmoact2-libero` | `dropbear.libero.observe` | 10 × 7 delta end-effector actions     | 10 Hz        |
| `molmoact2-droid`  | `dropbear.franka.observe` | 15 × 8 absolute joint/gripper targets | 15 Hz        |

## MolmoAct2 SO-101

### Observation

```python theme={null}
observation = dropbear.so101.observe(
    side_frame=side_rgb,
    wrist_frame=wrist_rgb,
    joint_positions=[
        shoulder_pan_deg,
        shoulder_lift_deg,
        elbow_flex_deg,
        wrist_flex_deg,
        wrist_roll_deg,
        gripper_position,
    ],
)
```

* `side_frame`: H×W×3 RGB image.
* `wrist_frame`: H×W×3 RGB image from a distinct arm-mounted camera.
* `joint_positions`: six finite values in LeRobot SO-101 order and degrees.
* `gripper_position`: LeRobot's 0–100 position convention.
* `actions_remaining`: optional nonnegative buffer depth; the policy loop sets
  this when needed.

### Action

Each returned action has this order:

```text theme={null}
[shoulder_pan, shoulder_lift, elbow_flex, wrist_flex, wrist_roll, gripper]
```

The values are absolute targets in the same degrees and gripper convention as
the observation. A normal chunk contains 30 actions for a 30 Hz controller.

On an underrun, the managed loop uses the current observation position as its
hold target. Your robot controller must still enforce per-tick changes, motor
limits, watchdogs, and the physical stop path.

## MolmoAct2 LIBERO

### Observation

```python theme={null}
observation = dropbear.libero.observe(
    agent_frame=agent_rgb,
    wrist_frame=wrist_rgb,
    state=[
        eef_x,
        eef_y,
        eef_z,
        axis_angle_x,
        axis_angle_y,
        axis_angle_z,
        gripper_qpos_0,
        gripper_qpos_1,
    ],
)
```

The eight state values are end-effector position, end-effector rotation as an
axis-angle vector converted from the environment's XYZW quaternion, then the
two simulator gripper joint positions.

### Action

A normal chunk contains ten 7D robosuite/LIBERO delta actions at 10 Hz:

```text theme={null}
[delta_x, delta_y, delta_z, delta_axis_x, delta_axis_y, delta_axis_z, gripper]
```

Use the action directly only with the matching LIBERO/robosuite environment
configuration. A physical robot controller has a different contract.

## MolmoAct2 DROID

### Observation

```python theme={null}
observation = dropbear.franka.observe(
    exterior_frame=exterior_rgb,
    wrist_frame=wrist_rgb,
    joint_positions=joint_radians,
    gripper=gripper_position,
    second_exterior_frame=second_exterior_rgb,
)
```

* `exterior_frame`: required H×W×3 `uint8` RGB view.
* `wrist_frame`: required H×W×3 `uint8` RGB view.
* `second_exterior_frame`: optional second exterior RGB view. When omitted,
  Dropbear maps the first exterior view to both exterior inputs.
* `joint_positions`: seven finite Franka joint positions in radians.
* `gripper`: one finite value from 0 (open) to 1 (closed).

### Action

Each returned action has this order:

```text theme={null}
[joint_0, joint_1, joint_2, joint_3, joint_4, joint_5, joint_6, gripper]
```

The values are absolute joint targets in radians followed by the unit-interval
gripper target. A normal chunk contains 15 actions for a 15 Hz controller.

<Warning>
  Dropbear provides DROID inference, not a Franka safety controller. Stop at
  `predict()` until your local stack validates joint, velocity, acceleration,
  workspace, collision, gripper, watchdog, and e-stop behavior.
</Warning>

## Validate at the boundary

For every model:

1. Record the raw controller state and the converted model state.
2. Assert camera color order, dtype, shape, and source identity.
3. Assert vector length, order, units, and finite values.
4. Inspect one non-actuating prediction.
5. Reject every output outside local limits before any coordinate conversion.
6. Test hold and e-stop behavior without cloud connectivity.

Continue to the [SO-101](/guides/so101) or [Franka](/guides/franka) recipe.