Document Generation

Epistola generates documents by combining a published template version with a JSON data payload. Three generation modes serve different use cases.

Synchronous preview

Used during template editing in the Suite. The editor sends preview requests and receives rendered output directly. Preview mode is rate-limited and does not produce PDF/A-compliant output.

Asynchronous single document

For production use. Submit a render request and receive a job ID immediately. The document is rendered in the background and produces a PDF/A-compliant, production-ready PDF.

Asynchronous batch

For high-volume scenarios. Submit an array of documents in a single request and receive a single job ID. Each document is tracked as a separate batch item with its own status.

Features

Variant resolution — Specify a variant explicitly by ID, or provide attributes for automatic resolution via the scoring algorithm
Environment selection — Target a specific environment to use the version deployed there
JSON Schema validation — The data payload is validated against the template’s data contract before rendering begins
Customizable filename — Set a custom filename for the generated document
Correlation ID — Attach a correlation ID for tracing through your systems

In the UI

The generation history dashboard shows:

Stats cards — Total jobs, queued, completed, and failed counts
Most-used templates — A table of the most frequently generated templates
Recent jobs — A filterable table of recent generation jobs with status badges