Open-source · Local-first · Real-time Decision Supervision

Agentic Sidecar — Runtime Governance

Pre-Alpha v0.6.1 PyPI

Agentic Sidecar attaches to your agent harness and evaluates every proposed tool call against policy, risk, intent, and budget limits before execution—without taking over the agent loop.

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361 Tests Passing
94% Code Coverage
v0.6.1 Release Preparation
0 Required Services
Sidecar Execution Flow
1. Agent Action Proposed
issue_refund(amount=$850)
LangGraph Adapter
2. Decision Gate Evaluation
Policy → Risk → Intent Guardian
Sidecar Runtime
3. Gate Verdict: BLOCK
Exceeds max refund constraint ($500)
Govern Mode
4. Adapter Action
Raises SidecarBlockedError (Tool Stopped)
Enforcement
Interactive Playground

Governed Customer Support Agent Demo

Test simulated agent actions against Policy Advisor, Risk Evaluator, Intent Guardian, and Budget Guardian in real time.

Operation Mode:
Execution Terminal ● Active Runtime
[SYSTEM] Governed Customer Support Agent initialized in GOVERN mode.
Click an action button above to evaluate tool calls against Sidecar rules.
Decision Payload Inspector JSON Data
// Select an action to view the serialized Decision & DecisionContext payload.
Design & Rationale

Core Architecture & Design Principles

Built on explicit governance boundaries rather than implicit LLM prompts.

⚡

Rules Before Models

Policy Advisor, Risk Evaluator, Intent Guardian, and Budget Guardian run deterministically with zero LLM latency or API costs. LLM Judges are strictly opt-in.

🔌

Framework Independence

The Sidecar runtime (core/) has zero dependencies on specific framework adapters. It attaches to LangGraph, CrewAI, or custom loops seamlessly.

🛡️

Fail-Safe Failure Modes

Requires an explicit on_sidecar_failure setting (fail_closed or fail_open). If evaluation errors, governance is guaranteed.

Modules & Capabilities

Composable Decision Gate Modules

Enable only the evaluation components your application requires.

📋

Policy Advisor

YAML-driven allow/deny permission rules matching tool names via glob patterns (delete_*).

⚖️

Risk Evaluator

Classifies actions into LOW, MEDIUM, or HIGH risk using tool argument pattern checks.

🎯

Intent Guardian

Validates tool parameters against structured user IntentEnvelope constraints and detects drift.

💰

Budget Guardian

Enforces per-task spend (USD) and token ceilings, returning PAUSE for human approval when exceeded.

🗺️

Plan Evaluator

Evaluates entire agent plans to detect unnecessary steps, overreach, or contradictory operations.

🔍

Critic & Judge Evaluators

Challenges decisions for unsupported assumptions and provides model-agnostic LLM decision review.

Operating Modes

Observe Mode vs. Govern Mode

Gradually transition from monitoring to active policy enforcement.

Mode Behavior Tool Execution Use Case
Observe Mode Evaluates tool calls, computes decision verdicts, and logs audit trails. Always Executes Initial deployment, shadow auditing, and baseline evaluation.
Govern Mode ALLOW/WARN proceed. BLOCK stops; other outcomes resolve through approval or suspend execution. Blocked via Exception Production enforcement, financial boundary control, and safety gating.
Developer Quickstart

Integration Code Snippets

Simple, pythonic integration with LangGraph and agent frameworks.

# Wrap tools for LangGraph agent
from agentic_sidecar import Sidecar
from agentic_sidecar.adapters.langgraph import attach
from agentic_sidecar.gate.policy import PolicyAdvisor, PolicyRule

sidecar = Sidecar(
    on_sidecar_failure="fail_closed",
    mode="govern",
    policy=PolicyAdvisor([PolicyRule(tool="delete_*", effect="deny")])
)

# Intercept tools before passing to react agent
tools = attach(sidecar, [read_order, issue_refund, delete_customer])
agent = create_react_agent(model, tools=tools)