TCGGraph documents webhooks for catalog changes and price-threshold events. They can reduce repeated checks for changes, but your receiver still needs signature verification, deduplication and a recovery path. A threshold alert must specify the market and the card it watches.
Which options should you evaluate?
| Option | What to evaluate | Decision detail |
|---|---|---|
| Catalog events | New sets, cards and record changes | Update the local record or schedule a catalog fetch. |
| Price watches | A configured threshold crossing | Preserve market and currency with the alert. |
| Reconciliation job | Periodic state checks | Recover from delivery failures or disabled endpoints. |
Provider facts come from the linked documentation. Examples and workflow recommendations are this guide’s analysis.
Choose events around product behavior
A new-set event might update a release browser. A card correction might refresh a cached record. A price crossing can notify a collector who explicitly requested that alert. Subscribe only to the games and events needed by the feature so the receiver does not create work that nobody uses.
Model an alert as a printing reference, marketplace, direction and threshold. A euro threshold on a European market is a different instruction from a dollar threshold on a US market. If finish or valuation type matters, retain that choice in the watch configuration and the displayed alert.
Verify the delivery before accepting the event
Validate the signature against the original request body using the documented signing scheme. Reject malformed or stale deliveries and store secrets on the server. Parse the JSON after the raw body is available for verification; reconstructing it from parsed data can change the signed bytes.
Treat the event ID as a deduplication key. TCGGraph documents at-least-once delivery, so repeated deliveries are a normal condition to handle. Queue the accepted work durably and acknowledge it promptly, then let a worker perform slower refreshes or user notifications.
Example: crossing a price threshold
A collector might ask for an alert when a chosen printing crosses below €25 on Cardmarket. Store the threshold and source together and explain that the event concerns a reference price, not a reserved listing. The collector still needs to check the actual product, seller and buying conditions.
TCGGraph describes crossing events rather than repeated notifications while a value remains below the threshold. An initial observation is also different from a change. Test first observation, downward crossing, repeated unchanged value and upward movement so the interface matches the event semantics.
Plan for downtime and reconciliation
Keep a delivery log with the event ID, receive time, processing state and failure reason. Retry your own processing without sending duplicate notifications. Use a periodic reconciliation job to compare important local records with the latest provider state after an interruption.
Review the provider’s retry and endpoint-disable behavior, and alert your team when the receiver stops processing. Webhooks reduce polling work but do not remove the need to monitor data freshness. Evaluate watch allowances and downstream API calls when comparing the plan cost.
Before you choose an API
- Verify the raw body and reject stale signatures.
- Deduplicate by event ID.
- Keep market and threshold together.
- Reconcile state after delivery failures.
Frequently asked questions
Are webhook deliveries included in TCGGraph data credits?
TCGGraph documents unmetered webhook deliveries, with a plan allowance for active price watches. Additional API requests your receiver makes still follow the relevant data billing rules.
Will a price alert fire every day a card stays cheap?
TCGGraph describes threshold crossings, so remaining below a threshold is different from crossing it. Build the notification copy around the documented event rather than promising daily reminders.
Can webhooks replace every scheduled refresh?
No. A reconciliation process remains useful for recovery and for data that has no applicable event. Combine events with a deliberate, lower-frequency refresh strategy.
Sources and further reading
Your next step with TCGGraph
Inspect the documented fields, then test the cards and workload your application needs.