Waitlist
Execution Memory Active
Works With Any Framework

The Safety Layer
For AI Agents.

Agents retry. They repeat everything - double charges, duplicate emails, redundant calls. ReplaySafe remembers what already happened, so retries skip what succeeded and resume from where they left off.

npm install @replaysafe/guard-sdk
⚡ Open source · Self-hostable · AGPL-3.0
Guard_Core
ReplaySafe
LangGraph Agent
Retry_Attempt_02
DEDUPED
Stripe Charge
ReplayGuard
SKIPPED
LLM Call
guard.ai()
CACHED
Execution Memory

Execution Memory.

Autonomous agents fail. It’s inevitable. But retrying a failed agent job shouldn't charge your customer twice or corrupt your database.

Intercept Side Effects

Automatically pause and verify dangerous actions (Payments, Emails, DB Writes) before they execute.

Result Replay

Replaysafe remembers the outcome of successful steps. On retry, we skip the action and replay the original result.

Retry_Attempt_02
JOB_ID: agent-992
Auth Check
Charge_CustomerIntercepted: Already Paid
SKIPPED
Send Receipt
ReplaySafe Insight

"ReplaySafe detected a successful payment fingerprint in Attempt_01. Execution halted to prevent double-spend. Replaying cached receipt."

Without ReplayGuard
// LangGraph node - UNSAFE on retry
async function chargeNode(state) {
  // ⚠️ On retry: charges TWICE
  const charge = await stripe
    .charges.create({
      amount: state.amount,
      customer: state.customerId,
    });
  return { chargeId: charge.id };
}
With ReplayGuard
// LangGraph node - SAFE on retry
async function chargeNode(state, guard) {
  // ✅ On retry: replays cached result
  const charge = await guard.langGraph(
    'stripe-charge',
    { amount: state.amount },
    () => stripe.charges.create({
      amount: state.amount,
      customer: state.customerId,
    })
  );
  return { chargeId: charge.id };
}

Infrastructure Visibility

Infrastructure Telemetry.

Know when the infrastructure your agents depend on starts to degrade - before a retry turns into a disaster.

Heartbeat Monitoring

Zero-config cron and job monitoring. If your background job stops reporting, ReplaySafe fires an alert before any agent retries into a broken state.

Silent Tunnel Detection

WireGuard and SSH tunnels fail silently - the process stays UP while data stops flowing. Sentinel detects stale handshakes and latency spikes before they break autonomous access.

Failure Pattern Intelligence

ReplaySafe tracks recurring failure windows, health score trends, and cascade incidents - giving agents and engineers actionable context, not just raw alerts.

Beyond Payments

Every Provider. One Safety Net.

ReplaySafe sits between your agents and ALL your side-effect providers - Stripe is just one of many.

💳
Stripe
Payments
📧
SendGrid
Email
📮
Postmark
Email
📬
AWS SES
Email
🐙
GitHub
Dev Tools
🦊
GitLab
Dev Tools
💬
Slack
Messaging
📱
Twilio
SMS / Voice
🪣
AWS S3
Storage
🤖
OpenAI
AI / LLM
🧠
Anthropic MCP
AI / LLM
🌐
Any HTTP API
Custom

Plus any operation via guard.effect()

Outbound Webhooks
Database Writes
LLM / AI Calls
Infrastructure (Terraform, K8s)
File Uploads
Custom REST APIs
Queue Messages
Cron / Scheduled Jobs
Early Access

Built for the Problems You're Already Hitting

ReplaySafe is in early access. We're working directly with engineering teams who are deploying AI agents in production and hitting the duplicate side-effect problem. If that's you, we want to hear from you.

The Double-Charge Problem

Agent charges a customer, DB write fails, agent retries - and charges again. ReplayGuard fingerprints the charge and skips execution on retry. The customer is never billed twice.

The LLM Retry Tax

Every agent retry re-runs every LLM call from scratch. guard.ai() caches completions - if the same call already ran, the cached result is returned. No second API bill.

The 50-Step Restart Problem

Agent runs 50 tool calls, fails at step 48, retries from scratch. ReplayGuard skips steps 1–47, resumes at 48. No duplicate side effects. No wasted compute.

Frequently Asked Questions

What is ReplaySafe?
Why not just use Stripe's idempotency keys?
What providers does ReplaySafe cover?
How does verification work?
What is the Execution Ledger?
How does agent crash recovery work?
Does it work with my existing orchestration framework?
Can multiple agents share execution memory?
What happens when something fails semantically?
Is ReplaySafe self-hosted?