0–15 mins: capture a clear baseline
Start by collecting a small set of known-good payloads from the sender (3–5 samples) and one or two of the proposed new payloads. Keep each sample as raw JSON in a single Google Sheet row or a simple file folder so you can compare them side by side.
Ask whoever owns the producing system to label samples with: source (app), endpoint name, time sent and an agreed schema_version field. If they can’t add a version flag, ask for a short changelog note describing anything intended to change (new fields, removed fields, renamed keys).
This is also the time to decide where the webhook will land for testing: a staging listener you control, a temporary test endpoint, or a captured Zapier/Make run. If you’re in Fareham or elsewhere on the South Coast and use marketing automation, keeping the test endpoint off production systems prevents accidental writes to your CRM while you test.
15–40 mins: compare and run quick validation tests
Line up keys and common paths between old and new samples. Manually or in a sheet, check for three fast failures: missing required fields, type changes (string → array, number → string) and enum/value-range shifts (status values, country codes, etc.). These three often break downstream logic.
Run simple validation checks you can do without engineering: required field present, value not null/empty, value format (email contains @, date parses, numeric fields parse), and string length limits. For automation platforms (Zapier/Make) add a filter or router step immediately after the catch module to run the same checks; for HubSpot or Salesforce receivers map incoming version to a property and gate workflows on that property.
If anything fails, fail loudly: respond with 4xx from your test listener or route the record to a quarantine list in a sheet. Silent accepts are the usual cause of mysterious downstream failures.
40–60 mins: add safe fallbacks, versioning and a rollout plan
Add a lightweight version field to the payload (schema_version) and require it in your consumer logic; treat missing or unrecognised versions as exceptions that go to a dead‑letter path. If you can’t change the sender, add a translation/mapping layer in Zapier/Make or your staging listener that annotates incoming payloads with an inferred version before they hit the CRM.
Create a simple dead‑letter/quarantine flow: write failed payloads to a shared Google Sheet, tag them in the CRM as "webhook-exception", and send a short alert (email/Slack) to the integration owner. For Zapier/Make add a separate route for failures that records the raw payload and a short reason column so a human can triage.
Finish with a smoke test: send 5 live test events (old and new versions) through the path and confirm the CRM (HubSpot, Salesforce) or automation behaves as expected. If you want extra help formalising this into a repeatable runbook or adding gating to HubSpot workflows, see our workflow automation support page for small teams: workflow automation for small teams. If you prefer, Optira can run this checklist and help set the quarantine and versioning pattern so your automations fail loudly, not silently.