# slbit Visualization Packet v1
Status: normative for slbit v0.1.0.
The schema identifier is:
```text
slbit/viz-packet/v1
```
A packet contains:
- semantic claim identifier and logical bit width;
- optional RGB color, icon, and layer name;
- a SHA-256 commitment to the transcript seed;
- ordered human-readable transcript rounds;
- a digest for every opaque round payload;
- a transcript digest over the exported round projection;
- a packet digest over all packet fields except `packet_digest`.
Packet JSON is compact UTF-8 with deterministic field ordering and JSON string
escaping. Control characters are rejected from semantic input fields.
## Trust Boundary
The packet is observation data. It MUST NOT be included in a Power House
`phx_fingerprint`, Rootprint branch ID, replay fingerprint, or proof-validity
decision.
The packet and transcript digests provide deterministic transport integrity.
They do not establish the soundness of an external proof.
## Limits
- claim identifier: 256 UTF-8 bytes;
- icon and layer/component labels: 128 UTF-8 bytes;
- note: 4,096 UTF-8 bytes;
- rounds: 1,000,000;
- opaque payload: 16 MiB per round.
Round numbers MUST increase strictly.