Install

Python

python3 -m venv .venv
source .venv/bin/activate
pip install haltstate-sdk

TypeScript

npm install @haltstate/sdk

Go

Stable baseline: v1.0.1. The Semiotic Probe preview is v1.1.0-dev.0, published on GitHub and verified through the Go module proxy.

go get github.com/haltstate-ai/sdk-go@v1.1.0-dev.0

These are explicitly selected previews, including replay-contract candidate APIs. They do not replace stable SDKs or activate replay routing. Existing integrations remain on the Standard contract. Semiotic Probes use an isolated model hook, the existing tenant API key, and the server-managed low-frequency schedule.

Java

The Semiotic Probe preview source is published on GitHub at v0.3.0-dev.0. Java 17 tests and local Maven publication pass. The JitPack package metadata and JAR are published and downloadable.

repositories { mavenCentral(); maven { url = uri("https://jitpack.io") } }
dependencies { implementation("com.github.haltstate-ai:sdk-java:v0.3.0-dev.0") }

These are explicitly selected previews, including replay-contract candidate APIs. They do not replace stable SDKs or activate replay routing. Existing integrations remain on the Standard contract. Semiotic Probes use an isolated model hook, the existing tenant API key, and the server-managed low-frequency schedule.

Rust

Install the Semiotic Probe preview directly from GitHub using this Cargo dependency:

haltstate = { git = "https://github.com/haltstate-ai/sdk-rust", tag = "v0.2.0-dev.0" }

All 22 SDK tests passed; a separate consumer fetched this tag and compiled the public probe API. No crates.io account is required.

These are explicitly selected previews, including replay-contract candidate APIs. They do not replace stable SDKs or activate replay routing. Existing integrations remain on the Standard contract. Semiotic Probes use an isolated model hook, the existing tenant API key, and the server-managed low-frequency schedule.

Service checklist

• Run workers with least-privilege API keys.
• Set fail-closed behavior for money, PII, and production writes.
• Use a stable idempotency key before the first guard call.
• Report execution only after the side effect has completed.
• Keep raw customer payloads out of public live events.

SDK availability

These are explicitly selected previews, including replay-contract candidate APIs. They do not replace stable SDKs or activate replay routing. Existing integrations remain on the Standard contract. Semiotic Probes use an isolated model hook, the existing tenant API key, and the server-managed low-frequency schedule.

Canonical API base

New integrations should use https://haltstate.ai as the public base URL and the HaltState-branded governance namespace. Existing clients may still support compatibility aliases, but public docs point new users at the current contract.

Implementation notes

Keep the HaltState call as close as possible to the side effect. The agent may plan and draft freely, but the wrapper around the actual action should be the place where authority is checked. That wrapper should send only the context required for policy evaluation: safe identifiers, normalized amounts, action names, risk flags, schedule windows, and redaction status. Raw customer payloads and secrets should stay in the business system or protected operator tooling.

Operational evidence

For each action, preserve the decision, the worker outcome, the idempotency key, safe resource references, latency, proof status, and redaction status. This evidence supports incident response and control narratives because it shows what the system did at runtime rather than only describing what the policy document intended. HaltState supports alignment work; it is not a substitute for legal advice or a compliance certification.