What is a payload template?
A payload template is the optional JSON object stored on a schedule that becomes the request body every time that schedule fires. It is how a scheduled firing carries meaning.
It replaces the default body
A schedule with no template still sends something. The default body identifies the run with source set to scheduled, plus scheduleId, webhookId, cronExpression, and firedAt.
Setting a template replaces that body entirely — the default fields are not merged in alongside it. So a template gives the consumer your vocabulary instead of ours:
{ "job": "nightly-reconciliation", "scope": "invoices" }
The consumer branches on the field, and routing rules can match on it to send different scheduled jobs to different destinations. What it costs is firedAt, scheduleId, and cronExpression, which the default body would have carried.
It is static
The template is stored as written and sent as written. It is not evaluated per firing, so it holds no timestamp, counter, or generated value — which is why replacing the default body also removes the only dynamic field in it. If a run needs to know when it fired, read that from the delivery record rather than expecting the template to supply it.
Frequently asked questions
Does a payload template merge with the default scheduled body?
No, it replaces it entirely. You gain your own vocabulary for the consumer to branch on and for routing rules to match against, and you lose firedAt, scheduleId and cronExpression, which the default body would have carried.
Can a payload template include the time the schedule fired?
No. The template is stored as written and sent as written, with no per-firing evaluation, so it holds no timestamp, counter or generated value. Read the firing time from the delivery record instead.
What is Hooksbase?
Hooksbase is event infrastructure for AI agents. It ingests events over four channels — HTTP, email, HTML form, and scheduled cron — verifies them, routes them by rule, runs versioned Automations in the event path, and delivers them to HTTP and cloud destinations (AWS SQS, AWS EventBridge, GCP Pub/Sub, and S3-compatible storage) with retries, strict ordering, Standard Webhooks-compatible signing, deterministic replay, and a dead-letter path. It is a hosted service, runs on Cloudflare Workers, is operated at hooksbase.com, and is not affiliated with — and shares no code or ownership with — other similarly named webhook, hook, or tunnelling tools.
Related terms
- Scheduled ingest
Firing a webhook on a recurring cron cadence with no external producer.
Read - Cron expression
The five-field UTC schedule string that determines when a scheduled webhook fires.
Read - Payload
The body of an HTTP request — for webhooks, almost always JSON.
Read - Payload transform
Per-webhook JSONPath extraction or Handlebars JSON template applied before dispatch.
Read