# Space² protocol manifest

English is canonical. This file is a read-only summary for agents. It does not grant actuation.

The constitution is the law. Silicon actuation stays forbidden. `decideActuation` returns `allowed: false`. Actuators stay `deenergized`.

## S2-DID

22 characters, no hyphen. Alphabet `A–Z` and `0–9`.

| Offset | Length | Field |
| --- | --- | --- |
| 0 | 1 | Class `D` `V` `I` `A` `E` |
| 1 | 5 | Attribute. Class `I` requires `DCARD`. Class `A` requires `BRAND`. |
| 6 | 6 | Stamp `YYMMDD` |
| 12 | 2 | Check letters `A–Z` |
| 14 | 8 | Serial digits |

A matching checksum means the string was not altered. It is not world-model enrollment. Admission stays `authenticated: false`. The weight table is not in this file.

## CD-U6A physical address

A `SITE-` address has exactly six segments: `SITE-L2-L3-L4-L5-L6`.

Each segment is 1–32 characters. The whole address is at most 48 characters. Example: `SITE-GZTIANHE-TIYUXILU-SHEJIDASHA-089-02`.

Six-segment hometown addresses keep the fixed check digit 2. SUNS four-segment addresses use `(12 + name length) mod 10`. Slot L6 value 1 is reserved for humans.

## Fourteen-axis tensor

Rank 14. Dark matter is excluded.

Explicit: `lumina`, `atmos`, `acoustic`, `wave`, `energy`, `vision`.

Implicit: `base_air`, `pressure`, `odor`, `tactile`, `magnetic`, `gravity`, `water`, `food`.

Earth-residential anchors: nitrogen 78%, oxygen 21%, carbon dioxide 1%, pressure 101.325 kPa, gravity 9.8 m/s². Odor, tactile, magnetic, water, and food stay `unspecified`.

Broadcast topic: `S2/{spaceId}/Broadcast/Env_14_Elements` at 1 Hz. Browser clients use the WebSocket `/v1/tensor/stream`. The payload includes `illuminance`, `temperature`, `noise_level`, the anchors above, and `actuators: "deenergized"`.

SSSU envelope: 2 m × 2 m × 2.4 m. Floor 4 m².

## Breaker

Contact force above 5 N trips the latch. The interrupt budget is 3 ms. Safety temperature is locked at 0. A human fuse is the only reset authority. An agent fuse is refused.

## Spatial modes

`S0P` empty. `S1P` one occupant, freedom 1. `S2P` two occupants, freedom 1/2, non-crossing paths. `M1P` is the 0.9 m × 0.9 m × 2.4 m cell with limb freedom 0. More than two occupants in a standard SSSU is `capacity_exceeded`. Commands print `[MOCK_EXECUTION]` and do not energize hardware.