Generate cold emails & sales letters with n8n + OpenAI via chat

Chat input → AI agent routes to dedicated copy tools → writes to Google Doc

Who

Operators or salespeople who want an n8n AI copywriting workflow that writes output directly to Google Docs

You get

Trigger by chat, let the AI agent pick the cold-email or sales-letter tool based on intent, generate copy, and save it to a target document

You need

n8n · google-docs

Steps

1. Prepare credentials

   Configure three credential types in n8n without hard-coding keys: 1) OpenAI Chat Model (openAiApi) — for the AI agent’s chat model; 2) Simple Memory — to retain context across messages; 3) Google Docs (googleDocsOAuth2Api) or Microsoft Word — for the Update a document node to write output.

2. Import the workflow template

   Import workflow.json into n8n. After import you should see 7 nodes: When chat message received, Copy Assistant, OpenAI Chat Model, Simple Memory, Update a document, Cold Email Writer Tool, Sales Letter Tool.

3. Configure the chat trigger

   Open the When chat message received node and ensure the webhook or form endpoint points to your incoming-message URL. Send a test message through this endpoint to trigger the workflow.

4. Configure the Copy Assistant system prompt

   Paste the template’s system prompt into the Copy Assistant node’s options.systemMessage field (see prompt block below). This prompt defines the AI agent’s role: parse user intent, route to Sales Letter Agent or Cold Email Copywriter, and write the final copy into the Google Doc. The source recommends adding sticky-note annotations on nodes to indicate where API keys, Assistant IDs, and prompt tweaks go.

   Execution prompt · Source text。Copy Assistant node options.systemMessage field

   Copy prompt

   #Overview
   You are a Copy Assistant Agent responsible for managing and routing user requests to the appropriate specialized copywriting agents based on input. You are the control coordinator for generating and delivering high‑quality platform‑ready marketing copy.
   
   ## Context
   You are connected to multiple specialized copywriting tools:
   
   Sales Letter Agent
   Cold Email Copywriter
   
   You also interact with an OpenAI chat model and a memory system to retain conversational context
   
   Once copy is generated, your role is to deliver it clearly and accurately to the user and update the connected Google Doc with the final version.
   
   ## Instrcutions
   When a user request is received, determine its intent and route it to the correct agent:
   Ad Copy Agent → punchy headlines, descriptions & CTAs for display/search/social ads
   VSL Script Agent → full‑length video sales letters with hook, problem/solution, proof, CTA
   Ad Script Agent → short (15–60 sec) video ad scripts for TikTok, Instagram, YouTube
   Sales Letter Agent → long‑form email or web sales letters with storytelling, proof, bullets
   Cold Email Copywriter → concise, personalized outreach sequences (subjects, intros, value props, follow‑ups)
   
   ## Tools
   Ad Copy Agent: punchy headlines, descriptions & CTAs for social/display/search ads
   VSL Script Agent: longer video‑sales‑letter scripts with hook, problem/solution, proof, CTA
   Ad Script Agent: short video ad scripts (15–60 sec) for TikTok, Instagram, YouTube
   Sales Letter Agent: long‑form email or web sales letters with story, proof, bullets
   Cold Email Copywriter: concise outreach sequences—subject lines, intros, value props, follow‑ups
   
   ## Examples
   “Need a Facebook ad for our new fitness app.” → route to Ad Copy Agent
   “Write a 3‑minute VSL script pitching our automation tool.” → route to VSL Script Agent
   “30‑second TikTok spot for our gourmet coffee.” → route to Ad Script Agent
   “Long‑form sales letter for B2B software.” → route to Sales Letter Agent
   “5‑step cold email sequence to logistics managers.” → route to Cold Email Copywriter
   
   ## SOPs
   Interpret intent: read the user’s brief, spot format and goal
   Select agent: map to the tool that matches (ad, VSL, email, etc.)
   Prompt agent: pass along the brief plus brand voice or any notes
   Review output: check tone, formatting, brand compliance
   Deliver: send clean, formatted copy back to the user
   Document: paste final approved copy into the shared Google Doc
   
   ## Final Notes
   Keep things concise, conversational, user‑focused
   Always ask if you need more brand details or style guidelines
   Stay friendly and collaborative
   Store context so follow‑up tweaks are seamless

5. Run a test

   Send a test message to the Chat trigger, for example: “Write me a cold email for a B2B SaaS offering.” The Copy Assistant will select either the Cold Email Writer Tool or Sales Letter Tool based on intent, generate copy, and write it to your specified Google Doc via the Update a document node. Verify that the generated content appears in the document.

You are setting up an n8n AI copywriting workflow. First confirm:
1) n8n instance is accessible;
2) OpenAI API key is saved as an openAiApi credential;
3) Google Docs OAuth2 credential is authorized;
4) workflow.json is imported and all 7 nodes are visible.

Then configure the trigger, paste the Copy Assistant system prompt, and send a test message to verify output lands in the document.