Agents that don’t
lose control.

JamJet is the open-source safety layer for AI agents — policy checks, audit trails, human approval, crash recovery, cost limits, memory, and MCP/A2A interoperability, without cloud or framework lock-in.

See what JamJet controls ↓ Get started in 60s

$ pip install jamjet

Not another agent framework. The safety layer behind them. Keep your stack — add JamJet when runs need to be replayable, auditable, and controlled.

B. Why we built it

Most of what breaks an AI agent in the real world isn’t model quality. It’s the boring stuff: a worker dies, a tool gets called wrong, a budget runs out, an audit team asks what happened. We built JamJet to make those things controllable, recordable, and recoverable — without forcing you to abandon LangGraph or CrewAI or whatever’s already working.

The runtime sits between your agent and everything it touches. Models, tools, memory, other agents — every interaction passes through a layer that can block, wait, record, and resume. Open source. Apache 2.0. Cloud-neutral.

How it fits with what you use →

C. What goes wrong, and what stops it

Six failure modes.
Six gates.

Other tools observe what agents do. JamJet actively prevents unsafe behavior, recovers from failures, and creates audit evidence — at the runtime layer.

01
Lost progress
A worker dies mid-run. JamJet replays the event log and resumes at the failed node.
02
Unsafe tool
An agent reaches for a tool it shouldn’t. The 4-level policy hierarchy blocks the call before execution.
03
Skipped approval
A high-risk action waits for a human. The run survives restarts. The decision lands in audit.
04
Runaway cost
A reflection loop won’t stop spending. The runtime halts the loop before it crosses the cap.
05
Missing audit
Compliance asks what happened. Every decision is in a signed, exportable evidence package.
06
Forgotten context
The agent forgets across sessions. Engram surfaces durable facts — not raw chat history.

See each failure mode in action →

“

Production isn’t a milestone. It’s the moment your code has to defend itself.

— a thing every serious engineer has learned the hard way

D. Watch one survive

Your agents crash.
Ours recover.

Every step is checkpointed as it happens. When a worker dies mid-run, the scheduler reclaims the lease and resumes from exactly where it stopped. No reruns. No duplicate side effects. No lost events.

Worker crashes — the Analyze step fails unexpectedly.
Lease reclaimed — scheduler detects the failure.
Resume from checkpoint — completed steps stay completed.
Zero events lost — full execution integrity preserved.

Run this demo →

E. Same runtime guarantees, two languages

Write Python or Java.
JamJet handles replay, policy, and recovery.

pipeline.py Python

from jamjet import task, workflow, approval

@task(model="claude-sonnet-4-6", max_cost=0.50)
async def analyze(data: dict) -> Report:
    """checkpointed, cost-capped"""

@workflow
async def pipeline(raw):
    report = await analyze(raw)     # crash-safe
    await approval(report)          # durable pause
    return await publish(report)

Pipeline.java Java

Agent analyst = Agent.builder()
    .name("analyst")
    .model("claude-sonnet-4-6")
    .strategy(Strategy.REFLECTION)
    .maxCost(0.50)                   // budget enforced
    .build();

WorkflowGraph pipeline = WorkflowGraph.builder()
    .node(analyst)                    // crash-safe
    .node(ApprovalGate.create())     // durable pause
    .node(publisher)
    .build();

Both compile to the same IR and run on the same Rust runtime. Java has its own native runtime too — zero sidecar, virtual threads, 8.9× faster than the REST sidecar in our benchmark.

F. When the team needs the cockpit

JamJet Cloud

The hosted control plane for agent runs. Trace timeline, policy violations, approval queue, cost guardrails, audit export, hosted Engram — across your team.

View Cloud Sign up free

G. Need memory first?

Start with Engram.

Open-source memory for MCP-native AI agents. Fact extraction, conflict detection, hybrid retrieval, consolidation. Use it standalone with Claude, Cursor, or any MCP client.

Add memory Source

“

We don’t replace your framework. We sit underneath it, like a seatbelt.

— the design intent, in one sentence

H. Running log

What we shipped lately.

Full blog →

Make agent runs
replayable, auditable,
and controlled.

$ pip install jamjet

Run the quickstart View JamJet Cloud GitHub

Apache 2.0 · Cloud-neutral · Framework-neutral · Built in Rust, Python, and Java.

Agents that don’t lose control.

Six failure modes.Six gates.

Your agents crash.Ours recover.

Write Python or Java.JamJet handles replay, policy, and recovery.