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

# Changelog

> Version history for SINT Protocol and products.

<Note>
  Detailed per-release notes live in the repo's `CHANGELOG.md`. This page is a human-readable overview. For the authoritative list, see [github.com/sint-ai/sint-protocol/blob/main/CHANGELOG.md](https://github.com/sint-ai/sint-protocol/blob/main/CHANGELOG.md).
</Note>

## v0.2 — April 2026

Major release. Protocol foundation laid, all twelve bridges shipping, conformance suite at 157 tests, 1,772 tests passing overall.

**Breaking changes:**

* Tier model consolidated from T1–T5 to T0–T3. Migration required for any v0.1 deployments.
* License for code confirmed as Apache-2.0 (some earlier docs erroneously listed MIT — now aligned).
* CSML definition locked as "Composite Safety-Model-Ledger" (earlier docs used "Continuous Safety Monitoring Language").

**Added:**

* Twelve transport bridges (MCP, ROS 2, A2A, IoT, MQTT Sparkplug, OPC UA, Open-RMF, gRPC, MAVLink, Swarm, Economy, HAL)
* Six formal invariants with informal proof sketches
* STRIDE+B threat model with worked attack chains
* 157-test conformance suite
* Compliance crosswalk (IEC 62443 / EU AI Act / NIST AI RMF / ISO 42001)
* Machine-readable tier crosswalk at `/v1/compliance/tier-crosswalk`
* Academic whitepaper (arXiv preprint in submission)

**Changed:**

* Policy Gateway latency target tightened to p99 \< 3ms for T0
* Evidence Ledger now requires SHA-256 hash chain with TEE signature option
* Capability token schema expanded with physical constraints block

**Deprecated:**

* v0.1 tier labels (T1–T5); will be removed in v0.4
* Legacy `/gate` URL path; use `/v1/intercept` instead

**Removed:**

* `/v0/` API surface

## v0.1 — Q3 2024

Initial public release. Proof-of-concept gateway, basic token model, in-memory ledger.

## Pre-v0.1 — 2024

Development snapshots. Not versioned publicly.

***

## Brand transition (April 2026)

SINT Labs refocused from consumer Web3 agent work (archived at [/archive](/archive/notice)) to physical-AI governance and the current product stack. Not a semver change to the protocol — a company-level direction change.

**What changed:**

* Brand and positioning aligned to lab + products + studio
* `@sinthive` → `@sintlabs` on X (handle rename, follower-preserving)
* Earlier Web3 content moved to `/archive/*`
* March 2025 whitepaper moved to `/archive/2025-whitepaper`
* docs.sint.gg reorganized around Getting Started / Protocol / Products / Developers / Archive

**What didn't change:**

* Existing \$SINT token-holder commitments
* Telegram community (channel renamed, content preserved)
* GitHub organization (`sint-ai` remains canonical)
* All existing protocol code and documentation

## Versioning policy

SINT Protocol follows semantic versioning:

* **Major** (v1 → v2): breaking API or schema changes
* **Minor** (v0.2 → v0.3): backwards-compatible additions
* **Patch** (v0.2.0 → v0.2.1): bug fixes only

Pre-1.0 minor versions may include breaking changes, announced at least one minor version in advance.