Description

n8n-nodes-justfill

Fill existing PDF forms from n8n data — including scanned and flattened PDFs
that have no form fields at all.

You set the layout up once, visually, with the
current workflow JSON from GitHub.
It accepts a PDF and JSON, maps values to reviewed field names, fills the
existing document, and returns a temporary download link.

The same workflow is published in the n8n template catalog.
Its current mapping and updated description were verified on October 5, 2026.

Installation

This community-node installation requires self-hosted n8n. The package is
not yet verified for n8n Cloud. On October 5, 2026, the Creator Portal showed
Changes Required: translate source comments and identifiers to English, and
remove the unused programmatic-node requestDefaults block. Version 0.1.6
addresses those review items; publication alone does not mean n8n approval.
The node submission is separate from the workflow-template review above.

Settings → Community Nodes → Install → n8n-nodes-justfill

Watch the 74-second uncut walkthrough:
install 0.1.5, test a new masked credential, list fields, fill and open a synthetic
PDF, then let AI Agent 2.2 call the field-listing tool with a local CPU model.
The agent example was prepared before recording. This is a working demonstration,
not n8n approval. The recording shows 0.1.5; version 0.1.6 changes source
naming and comments and removes unused configuration, retaining the workflow
parameters and operations.

If your source is already Excel or CSV and you do not need n8n yet, use the

List Fields does not pass the binary PDF through. Use it to inspect the
mapping, then change the operation to Fill PDF, or supply the original PDF
again on a separate filling branch. Connecting its output directly to Fill PDF
without restoring the binary file will not work.

{ "Patient name": "Example Patient", "Date": "2026-09-06" }

Start from the AI Agent 3.1 example.
Import it into self-hosted n8n, follow its setup note, then select your own
JustFill and local Ollama credentials. The example contains no keys or pinned
results and only lists saved fields; it does not generate or deliver PDFs.

Keep the workflow execution order at v1. If you create workflow JSON or
use the REST API, set this explicitly:

{ "settings": { "executionOrder": "v1" } }

On n8n 2.34.4, omitted settings select the legacy execution order. In our
Agent 3.1 test that resumed the agent before its JustFill tool had finished,
so the answer reported an empty result despite correct tool output.

A tool call does not automatically receive the agent’s binary input. Leaving
Input Binary Field at data can fail even when the PDF is visible in the
agent’s preceding step. In the tool, switch that parameter to Expression
and reference the node that downloaded the original PDF:

{{ $('Synthetic PDF').item.binary.data }}

Replace Synthetic PDF and data with your actual node and binary-property
names. This passes the binary object to n8n’s binary helper; it is not a URL,
base64 text or an AI-generated file reference. Keep the source selection under
workflow control, not $fromAI().

The following single-PDF setup was tested on September 6, 2026:

• Self-hosted n8n 2.34.4, JustFill package 0.1.5, AI Agent node

3.1 with executionOrder: v1; the earlier video uses node 2.2
(typeVersion in workflow JSON).

• Manual Trigger → HTTP Request (file response) → AI Agent, with JustFill

connected as a tool, operation List Fields, using the expression above.

• Tool name listpdffields; manual description:

Read the saved field names of the attached supplier intake PDF.

• Local Ollama 0.33.1, qwen3:0.6b, thinking off, temperature 0,

context 2048, maximum 256 output tokens. No cloud model was used.

• Agent system message: You are a helpful assistant. Prompt:

List the field names of the attached supplier intake PDF. Use the listpdffields tool. Do not guess field names.

The execution trace contained a real tool call, the three saved field names in
its observation, and the same names in the agent’s answer. Earlier prompts
returned text or an empty array without invoking the tool: a green workflow
status alone is not enough. Check the tool execution and observation.

Correction, September 6: the earlier Agent 3.1 warning was too broad.
An omitted-settings control reproduced the empty observation. Two fresh 3.1
executions with executionOrder: "v1" both received the exact tool result and
returned all three field names. The node package and n8n runtime were unchanged;
no downgrade or core patch was needed. This matches the scheduling issue
described in n8n #26202, which is
closed as not reproduced, not marked fixed. Do not change a production
workflow’s execution order without checking its other branches too.
Multi-item agent workflows have not been validated by this single-PDF check.

This example lists fields; it does not demonstrate agent-driven PDF delivery.
Use ordinary workflow nodes for filling and handling the binary PDF output.
The walkthrough linked above includes this scoped tool action alongside ordinary
PDF filling. That video still demonstrates Agent 2.2; the later 3.1 comparison
is separate execution evidence, not a replacement video or n8n approval.

Notes

• Start from a blank source. Omitted, null and empty-string values are not

submitted; do not use them to clear existing or default values in the PDF.
Checkboxes take "true", "yes" or "x".

• Fail on Unknown Field is on by default. Leaving it on is how you find out

that a column was renamed, instead of shipping a half-empty form.

• Flatten bakes filled native form fields into the page. Turning it off can

retain existing editable fields, but does not create new ones on a scanned
or flattened PDF. This node does not request the API’s separate fillable-PDF
creation mode.

Licence

MIT