Trigger filters

Filter-tree syntax for the Tellzm Trigger node.

The Tellzm Trigger node accepts an optional filter tree so a workflow only fires for events that match. Leave blank to receive every event of the chosen type.

Shape

A filter tree is either a single condition or a group:

jsonc

// Single condition (leaf)
{ "field": "status", "op": "eq", "value": "done" }

// AND group
{
  "combinator": "AND",
  "conditions": [
    { "field": "priority", "op": "in", "value": ["urgent", "high"] },
    { "field": "assignee.id", "op": "eq", "value": "{{ $json.userId }}" }
  ]
}

// Nested
{
  "combinator": "OR",
  "conditions": [
    { "field": "status", "op": "eq", "value": "blocked" },
    {
      "combinator": "AND",
      "conditions": [
        { "field": "dueDate", "op": "lt", "value": "{{ $now.toISODate() }}" },
        { "field": "completedAt", "op": "exists", "value": false }
      ]
    }
  ]
}

Operators

Op	Means	Value type
`eq`	equal to	scalar
`neq`	not equal	scalar
`in`	value is one of the array	array
`nin`	value is NOT one of the array	array
`lt` / `lte`	less than (or equal)	number or ISO date
`gt` / `gte`	greater than (or equal)	number or ISO date
`contains`	substring match on string	string
`exists`	field is present and non-null	boolean — pass `true` to require, `false` to forbid

Combinators

AND — every nested condition must match
OR — at least one nested condition must match

Maximum depth is 8 levels and a group can hold up to 50 conditions.

Available fields

Field names follow the event's payload structure. Common ones:

Event	Useful fields
`task.*`	`id`, `title`, `status`, `priority`, `projectId`, `assigneeId`, `tags`, `dueDate`, `parentId`, `createdAt`
`project.created`	`id`, `name`, `slug`, `workspaceId`, `creatorId`, `processTemplateId`
`form.submitted`	`formId`, `submissionId`, `respondentId`, `values.<fieldId>`
`page.published`	`pageId`, `title`, `workspaceId`, `publishedBy`
`record.upserted`	`tableId`, `recordId`, `values.<fieldId>`
`calendar.event.created`	`eventId`, `subCalendarId`, `startsAt`, `endsAt`
`comment.added`	`commentId`, `entityType`, `entityId`, `authorId`

Use dotted paths for nested fields — assignee.id, values.fld_abc.

Tips

The filter runs server-side before n8n is hit, so filtering aggressively reduces both bandwidth and credit-counted invocations.
n8n expressions inside values ({{ $json.x }}) are resolved by n8n at workflow run time, not by Tellzm. Keep values literal in the filter unless you really need workflow-local data.
If a workflow never fires when you expect it to, switch your filter off temporarily and add it back one condition at a time.

[!TIP] Start broad, then narrow. It's easier to start with an empty filter (fires for every event), watch one or two runs to see the actual payload shape, then add conditions — than to guess the field names from the docs.