Create Custom PDF Documents from Templates with Gemini & Google Drive

Nodes

+7

1 — What Does It Do / Which Problem Does It Solve?

This workflow turns Google Docs-based contract & form templates into ready-to-sign PDFs in minutes—all from a single chat flow.

Automates repetitive document creation. Instead of copying a rental, sales, or NDA template and filling it by hand every time, the bot asks for the required values and fills them in.
Eliminates human error. It lists every mandatory field so nothing is missed, and removes unnecessary clauses via conditional blocks.
Speeds up approvals. The final draft arrives as a direct PDF link—one click to send for signing.
One template → unlimited variations. Every new template you drop in Drive is auto-listed with **zero workflow edits—**it scales effortlessly.
100 % no-code. Runs on n8n + Google Apps Script—no extra backend, self-hosted or cloud.

2 — How It Works (Detailed Flow)

📝 Template Discovery

📂 The TemplateList node scans the Drive folder you specify via the ?mode=meta endpoint and returns an id / title / desc list. The bot shows this list in chat.
🎯 Selection & Metadata Fetch

The user types a template name.

🔍 GetMetaData opens the chosen Doc, extracts META_JSON, placeholders, and conditional blocks, then lists mandatory & optional fields.
🗣 Data-Collection Loop
- The bot asks for every placeholder value.
- For each conditional block it asks 🟢 Yes / 🔴 No.
  
  Answers are accumulated in a data JSON object.
✅ Final Confirmation

The bot summarizes the inputs → when the user clicks Confirm, the DocProcess sub-workflow starts.
⚙️ DocProcess Sub-Workflow

🔧 Step

Node

Task

1

User Choice Match Check

Verifies name–ID match; throws if wrong

2

GetMetaData (renew)

Gets the latest placeholder list

3

Validate JSON Format

Checks for missing / unknown fields

4

CopyTemplate

Copies the Doc via Drive API

5

FillDocument

Apps Script fills placeholders & removes blocks

6

Generate PDF Link

Builds an export?format=pdf URL
📎 Delivery

The master agent sends 🔗 Download PDF & ✏️ Open Google Doc links.
🚫 Error Paths
- status:"ERROR", missing:[…] → bot lists missing fields and re-asks.
- unknown:[…] → template list is outdated; rerun TemplateList.
- Any Apps Script error → the returned message is shown verbatim in chat.

3 — 🚀 Setup Steps (Full Checklist)

Goal: Get a flawless PDF on the first run.

Mentally tick the ☑️ in front of every line as you go.

☁️ A. Google Drive Preparation

Step

Do This

Watch Out For

1

Create a Templates/ folder → put every template Doc inside

Exactly one folder; no sub-folders

2

Placeholders in every Doc are {{UPPER_CASE}}

No Turkish chars or spaces

3

Wrap optional clauses with [[BLOCK_NAME:START]]…[[BLOCK_NAME:END]]

The START tag must have a blank line above

4

Add a META_JSON block at the very end

Script deletes it automatically after fill

5

Right-click Doc > Details ▸ Description = 1-line human description

Shown by the bot in the list

6

Create a second Generated/ folder (for copies)

Keeps Drive tidy

🔑 Folder ID (long alphanumerical) = <TEMPLATE_PARENT_ID>

We’ll paste this into the TemplateList node next.

Simple sample template → Template Link

🛠 B. Import the Workflow into n8n

Settings ▸ Import Workflow ▸ DocAgent.json

If nodes look Broken afterwards → no community-node problem; you only need to select credentials.

📑 C. Customize the TemplateList Node

Open Template List node ⚙️ → replace

'%3CYOUR_PARENT_ID%3E' in parents

with the real folder ID in the URL.
Right-click node > Execute Node.
Copy the entire JSON response.
In the editor paste it into:
- DocAgent → System Prompt (top)
- User Choice Match Check → System Prompt (top)
  
  Save.