Open Source · Alpha Access Available

Put a Harness on Your AI Agent Workflows.

The open-source evaluation engine and low-latency proxy built to keep multi-agent systems and non-deterministic flows within strict operational, security, and cost boundaries.

govern.tstypescript
1import { FlowHarness } from '@flowharness/core';
2import { MyAgenticCrew } from './crew';
3
4// Initialize your evaluation and governance boundaries
5const harness = new FlowHarness({
6 apiKey: process.env.FLOW_HARNESS_KEY,
7 rules: ['no-hallucinations', 'pii-leak-protection', 'zombie-loop-detection'],
8 maxTokenSpendPerFlow: 0.50, // Strict cost boundary
9 failSafe: { action: 'fallback', message: 'Agent reached non-deterministic boundary.' }
10});
11
12// Intercept, trace, and govern the live agent loop
13const governedFlow = harness.wrap(MyAgenticCrew);
14const result = await governedFlow.execute({ input: userQuery });

Enterprise-grade governance, developer-first experience.

FlowHarness gives engineering teams real-time observability and control over their most unpredictable systems—autonomous AI agents.

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Real-Time Guardrails

Sit as an ultra-low latency proxy between your application logic and LLMs. Dynamically intercept and block prompt injections, toxic outputs, and PII leaks before data ever reaches the client.

Multi-Agent Traceability

Don't settle for single-turn prompt logging. Map complex agentic chains (like CrewAI loops), track sub-agent handoffs, audit runtime tool-execution paths, and pinpoint exactly where logic breaks down.

Cost Guardrails & Zombie Detection

Prevent runaway costs. Automatically kill recursive "zombie loops" where autonomous agents get stuck executing tools in infinite cycles. Set hard token-spend ceilings per operational execution flow.

Prevent 'Context Rot'

Ensure vector store alignment and context hygiene. Evaluate prompt regression and semantic drift automatically in your CI/CD pipelines to guarantee that underlying model updates don't break existing product logic.

Data Sovereignty

Data Gravity Sovereign

FlowHarness is built as a source-available, open-core engine. Keep 100% of your sensitive prompt logs inside your own cloud network (AWS/GCP VPC or On-Prem). No third-party data sharing, fully compliant with strict corporate data governance.

SOC 2 ReadyVPC DeployableZero Data EgressOn-Prem Compatible

Ready to govern your AI agents?

Join engineering teams building the next generation of reliable, auditable, and cost-controlled AI systems.