nodus-extensions

Typed, versioned, sandboxed extension loading for Nodus AI systems.

Provides ABI versioning constants, a hook lifecycle runner, subprocess and OCI sandbox runners, disk-discovery extension registry, and a provenance inventory. No required external dependencies — pure stdlib.

Note on naming: This package (nodus-extensions, plural) is distinct from nodus-extension (singular). nodus-extension is the nodus-lang companion that provides .nd script bindings (import "nodus-extension"). This package is a standalone Tier 4 library for building extension-hosting platforms in Python.

Status: v0.1.0 — prepared, not yet published.

Install

pip install nodus-extensions

What it provides

ExtensionManifest

from nodus_extensions import (
    ExtensionManifest, SandboxTier,
    MANIFEST_ABI_V1, AGENT_TOOL_REGISTRATION_ABI_V1ALPHA1,
    SURFACE_AGENT_TOOL, OWNER_EXTERNAL_THIRD_PARTY,
)

manifest = ExtensionManifest(
    name="myapp.greet-extension",
    version="1.0.0",
    description="Greets users",
    abi_version=MANIFEST_ABI_V1,
    sandbox_tier=SandboxTier.INSECURE_DEV,
    surfaces=[SURFACE_AGENT_TOOL],
    capabilities=["tool.invoke"],
)

ABI version constants

ExtensionRegistry

from nodus_extensions import ExtensionRegistry

registry = ExtensionRegistry()
registry.discover("/path/to/extensions/")   # scans for nodus-extension.json files
registry.load("/path/to/specific-ext/")     # load one extension dir

ext = registry.get("myapp.greet-extension")  # ExtensionManifest | None
all_exts = registry.list_all()               # list[ExtensionManifest]
registry.unload("myapp.greet-extension")

HookRunner

from nodus_extensions import (
    HookRunner,
    PHASE_INIT, PHASE_BEFORE_AGENT_START,
    PHASE_BEFORE_MODEL_RESOLVE, PHASE_AFTER_AGENT_END, PHASE_SHUTDOWN,
)

runner = HookRunner()

def my_init_hook(params: dict) -> None:
    print("Initialising:", params)

runner.register(PHASE_INIT, "my-hook", my_init_hook)
await runner.run(PHASE_INIT, {"context": "startup"})
runner.unregister(PHASE_INIT, "my-hook")

Hooks are async-aware — sync hooks are called directly; async hooks are awaited. All hooks for a phase run in registration order.

Sandbox runners

from nodus_extensions import SubprocessSandboxRunner, OciSandboxRunner, make_runner, SandboxTier

# Subprocess (insecure-dev — same OS user as host)
runner = SubprocessSandboxRunner()
result = runner.run("python3 extension.py", input_data={"tool": "greet", "args": {}})
# result.ok, result.stdout, result.stderr, result.returncode, result.output

# OCI container (Docker required)
runner = OciSandboxRunner(image="myapp/greet-extension:1.0")
result = runner.run("python3 extension.py", input_data={...})

# Factory
runner = make_runner(SandboxTier.INSECURE_DEV)
runner = make_runner(SandboxTier.CONTAINER)

Provenance

from nodus_extensions import ExtensionProvenance, ProvenanceInventory, derive_trust_class

inventory = ProvenanceInventory()
prov = ExtensionProvenance(
    name="myapp.greet-extension",
    source="local",
    owner_class="personal",
    trust_class=derive_trust_class("personal"),
)
inventory.record(prov)

all_prov = inventory.list_all()
entry = inventory.get("myapp.greet-extension")

Design

• No required dependencies. Pure stdlib (asyncio, threading, subprocess, importlib, pathlib, json, logging).
• Thread-safe. ExtensionRegistry and ProvenanceInventory use threading.Lock.
• Sandbox tiers are explicit. SandboxTier.INSECURE_DEV (subprocess) and SandboxTier.CONTAINER (OCI) are named constants, not flags.

Development

pip install -e ".[dev]"
pytest tests/ -q

License

MIT — see LICENSE.