python

agent-hooks (Python SDK)

Python implementation of AGENT-HOOKS-0.1: interception-point enums, AgentContext builder, Verdict types, host-side InterceptionEmitter with the four composition profiles, the pluggable identity-provider seam, and the Conformance Test Kit.

Trust model. agent-hooks is a cooperative contract, not a security boundary: the host framework is fully trusted, interceptors run in-process with full data access, and no complete-mediation claim is made. Read SECURITY.md and spec §1.4 before relying on it.

# The 0.1.0a1 artifact on PyPI implements a superseded draft — until
# 0.1.0a2 is published, install from source:
pip install "agent-hooks-sdk[ctk] @ git+https://github.com/responsibleai/agent-hooks.git#subdirectory=sdk/python"
# import name: agent_hooks

Host (framework adapter) usage

from agent_hooks import AgentContextBuilder, InterceptionBlocked, InterceptionEmitter

builder = AgentContextBuilder(agent_id="my-agent", framework="my-fw", session_id="s-1")
emitter = InterceptionEmitter().register(MyPolicy())

await emitter.emit(builder.agent_startup(tools_registered=["http_get"]))
ctx = builder.pre_tool_call(call_id="tc-1", name="http_get", args={"url": url})
try:
    await emitter.emit(ctx)
except InterceptionBlocked as e:
    return tool_error(e.result.verdict.reason)
result = invoke_tool(ctx["tool_call"]["args"])  # post-transform args

Interceptor usage

from agent_hooks import AgentContext, Verdict


class MyPolicy:
    def intercept(self, ctx: AgentContext) -> Verdict:
        if ctx["interception_point"] == "pre_tool_call" and ctx["tool_call"]["name"] == "rm":
            return Verdict.deny(reason="dangerous")
        return Verdict.allow()

Verdict.allow(), Verdict.deny(...), Verdict.warn(...) (allow + recorded warning) and Verdict.escalate(...) (liftable deny for the approval seam, §9) are the constructor shortcuts for the §5 shapes.

Running the CTK against your framework

Implement agent_hooks.ctk.Harness (see conformance/HARNESS.md), then:

pytest --agent-hooks-harness=my_pkg:MyHarness

The vectors ship inside the wheel; pass --agent-hooks-vectors=<dir> only to run a different vector set.