zu-runtime 0.4.0

An opinionated, backend-agnostic runtime for agents that work in production — deterministic, auditable, injection-resistant. Import as `zu`.

Zu

An opinionated, backend-agnostic runtime for agents that work in production — deterministic, auditable, and injection-resistant by construction.

New here? One line:

pip install 'zu-runtime[all]'       # everything: web tools, both model SDKs, server, Docker, MCP

Prefer a lean install? pip install zu-runtime gives you import zu, the zu command, the web tools (http_fetch/html_parse/render_dom), the model-provider adapters, detectors, validators, and a SQLite event sink. Add the heavy/situational bits as extras:

pip install 'zu-runtime[anthropic]' # + the Anthropic SDK to call a real model (also: [openai])
pip install 'zu-runtime[serve]'     # + the HTTP server (zu serve)
pip install 'zu-runtime[docker]'    # + the Docker sandbox (tier-2 browser)
pip install 'zu-runtime[mcp]'       # + the MCP server (zu mcp)

The zu-* packages are also standalone on PyPI, but you rarely install them individually — that's for plugin authors depending on just zu-core.

Embed it

import zu

result = zu.run(
    {"query": "Extract the product name and price.",
     "target": "https://example.com/product/123",
     "output_schema": {"type": "object",
                       "properties": {"name": {"type": "string"}, "price": {"type": "string"}},
                       "required": ["name", "price"]}},
    config={"provider": {"name": "anthropic", "model": "claude-sonnet-4-6",
                         "api_key_env": "ANTHROPIC_API_KEY"},
            "plugins": {"tools": ["http_fetch", "html_parse", "render_dom"],
                        "detectors": ["empty", "error", "js-shell", "bot-wall"],
                        "validators": ["schema", "grounding"]}},
)
print(result.status, result.value)

Swapping the model is a one-line edit to the provider block — Anthropic, OpenRouter, OpenAI, or a local model (Ollama / vLLM) — because the runtime only ever speaks to a ModelProvider port. Credentials are named by environment variable (api_key_env), never passed in code or config.

Run it from the command line, or as a service

zu run agent.yaml             # one-shot
zu run agent.yaml --every 5m  # scheduled worker
zu serve -c agent.yaml                     # HTTP: POST /run  (needs the [serve] extra)

What it is

A small, stable core (the loop, registry, contracts, event bus) surrounded by six swappable ports. Every capability that can vary is a plugin behind a port, so the production system is reached by adding adapters — never by reopening the core. Full source, architecture, and examples: https://github.com/k3-mt/zu

Apache-2.0.