Sandbox — Supply Partners

The sandbox is a production-identical environment that uses synthetic DSP demand instead of real money. Test your VAST tags and RTB integration before going live — no budget risk, no impact on real revenue.

How sandbox works

	Sandbox	Production
Auction engine	Identical	Identical
DSP demand	Synthetic (test bidders)	Real DSPs
Revenue	Not real — display only	Real payout
Data isolation	Separate Redis namespace	Live data
VAST endpoint	Same URL + `sandbox=true`	Same URL
Reset	Flush anytime	No flush

Enable sandbox on a supply source (Publisher)

Open the supply source in your dashboard

Toggle sandbox mode

Under Settings, enable Sandbox Mode and click Save.

Verify the sandbox flag

The supply source card shows a Sandbox badge. The supply source now only participates in sandbox auctions.

A supply source can only be in one mode at a time — sandbox or live. To test new inventory before going live, create a duplicate supply source in sandbox mode.

Sandbox VAST tag URL

Use the same VAST endpoint with sandbox=true appended:

https://rtb.praevis.com/vast?site_id={PUBLISHER_ID}&w={WIDTH}&h={HEIGHT}&ip={IP}&ua={UA}&sandbox=true

Or set it via the x-sandbox: true header on RTB requests.

Expected sandbox responses

Synthetic DSPs return bids at randomised CPMs designed to mimic real fill rates (~70–80%). You’ll see a mix of filled and empty responses — this is intentional.

<!-- Filled response example -->
<?xml version="1.0" encoding="UTF-8"?>
<VAST version="4.0">
  <Ad id="sandbox-ad-001">
    <InLine>
      <AdSystem>Praevis Sandbox</AdSystem>
      <AdTitle>Sandbox Test Creative</AdTitle>
      <Creatives>
        <Creative>
          <Linear>
            <Duration>00:00:15</Duration>
            <MediaFiles>
              <MediaFile type="video/mp4" width="1920" height="1080" bitrate="2000">
                https://sandbox.praevis.com/test-creative-15s.mp4
              </MediaFile>
            </MediaFiles>
          </Linear>
        </Creative>
      </Creatives>
    </InLine>
  </Ad>
</VAST>

<!-- Empty response (no bid) -->
<?xml version="1.0" encoding="UTF-8"?>
<VAST version="4.0"/>

Reading sandbox metrics

Sandbox metrics appear in the dashboard separately from live metrics.

Go to the main dashboard
Click the Sandbox toggle in the time period selector
You’ll see RPS, fill rate, and revenue for sandbox auctions only

⚠️

Sandbox revenue figures are for testing only. They do not accrue to your account and will not appear on invoices.

Pre-go-live checklist

Run through this before switching a supply source to live:

VAST tag returns a filled response at least once in sandbox
Empty VAST response parsed correctly (no error in your ad server)
Revenue tracked in sandbox dashboard (proves impression tracking works)
VAST validated with a VAST Inspector tool (e.g., Google VAST Inspector)
RTB bid request received and bid response returned correctly (if using RTB mode)
Floor price set — check that synthetic bids are winning above it

Once all boxes are checked, disable sandbox mode on the supply source and point your ad server at the live URL (remove sandbox=true).

Resetting sandbox data

Sandbox data can be flushed without affecting production:

POST /api/sandbox/reset
X-API-Key: {YOUR_API_KEY}

This resets all sandbox metrics and auction logs for your partner account. Useful for a clean baseline before a validation run.

→ Full sandbox guide

RTB Integration Inventory Pools