Guide
Custom instructions for sales reps: what goes in, what stays out
A sales rep's custom instructions should hold what's true in every chat: what you sell and to whom, your tone, and the rules that keep you out of trouble. Those rules are facts about a prospect only from your research, no prices or discounts without approval, and the lines every US cold email needs under CAN-SPAM: a line that it's a sales message, a postal address and an opt-out honored within 10 business days. Price lists and account notes stay out; they belong in a sales project, and the emails you write every day belong in a skill that carries their rules. Keep it short; OpenAI's help page, read through search-result text, gives 1,500 characters on Free and Go and 5,000 on Plus and above.
Short answer
- In: what you sell, to whom, your tone.
- In: research-only facts; no prices without approval.
- In: the CAN-SPAM lines for every cold email.
- Out: price lists and account notes; emails become skills.
What goes in, and what stays out
| Line | Where it goes |
|---|---|
| What you sell, to whom, your tone | Custom instructions |
| Facts about a prospect only from your research; mark gaps | Custom instructions |
| No prices or discounts without approval | Custom instructions |
| The CAN-SPAM lines for cold email | Custom instructions, and the email skill |
| Price sheet, discount rules, product facts | A sales project, on a business plan |
| A prospect's account notes | Your CRM, not the chat's instructions |
| First emails, follow-ups, call prep | Skills |
A worked example
Illustration: a made-up business. An SDR at a 30-person company selling scheduling software to US restaurant groups had the full price list and a "20% off this month" line in her custom instructions. The price list moved to her sales project and the discount line was deleted, since discounts need her manager's approval. What stays, at 554 characters:
Custom instructions: SDR
I'm an SDR at a 30-person company selling scheduling software to US restaurant groups. Plain, short sentences; no hype words.
Use only facts from my research or the product file in my Sales project. Never invent a prospect's numbers, quotes or tools; mark gaps [check].
Never quote a price or a discount; prices and approvals are in the project.
Every cold email ends with: a line that it's a sales message, our postal address, and how to opt out; opt-outs are honored within 10 business days.
For first emails and follow-ups, use my cold-outreach skill.
Her next first email to a restaurant group ended with "A sales message from Tablesync · [postal address] · Reply 'no thanks' and I won't email again", and it didn't mention the discount the old instructions had offered to everyone.
Next step: one playbook for the team
Once your own instructions are right, the team needs the same rules in every rep's AI. ChatGPT for sales teams: a one-page AI playbook covers writing them once for everyone.
Skills for this
- SalesCold outreach emailWrites a first-touch cold email under 90 words from your research: one specific observation, one problem, one easy ask, and 2 subject lines.
- SalesSales follow-up emailWrites the follow-up after a sales call: a recap in the buyer's words, the next step with a date, one ask, plus day 3, day 7 and breakup nudges.
- SalesDiscovery call prepBuilds a one-page discovery call prep from the prospect's website, LinkedIn and notes: hypotheses, 8 ranked questions, what to qualify, red flags.
- AI practiceContext brief for an AI assistantWrites instructions for an AI assistant or agent: role, audience, can and can't, sources of truth, tools, format, examples, edge cases, and handoff.
Questions
What should sales reps put in ChatGPT custom instructions?
What holds in every chat: what you sell, to whom, your tone, the rule that facts about a prospect come only from your research, no prices or discounts without approval, and the lines every cold email needs. Point to where product facts and prices live, in a project, instead of pasting them.
Should price lists go in custom instructions?
No. Prices change and need approval, and custom instructions are read in every chat, including ones where a number shouldn't appear. Keep the price sheet and the discount rules in your sales project, and tell the AI never to quote a price itself.
What does a cold email need by law in the US?
CAN-SPAM covers it, business-to-business included, per the FTC's guide: identify it as an ad (a line that it's a sales message), include a valid postal address, and give a way to opt out, honored within 10 business days. A cold email goes to someone who didn't ask for it, so the ad line always stays. Never send to bought lists; Gmail's guidelines say not to buy addresses.
AI skill
Have your AI write cold emails that get replies
Put this skill in AI Skill Pod and everyone on your team gets it in their Claude, Cursor or ChatGPT (Pro, Business, Enterprise): one invite link, free to start. With Cold outreach email, each rep's AI writes the first email your instructions point to: one observation only this prospect could get, one problem, one easy ask, under 90 words, two short subject lines, and the CAN-SPAM lines a sales email needs: a line that it's a sales message, a postal address and an opt-out.
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Sources
- OpenAI Help: ChatGPT custom instructions — up to 1,500 characters on Free and Go, 5,000 on Plus, Pro, Business, Enterprise and Education; read through search-result text, the page blocks automated reads (read 2026-11-05)
- FTC: CAN-SPAM Act, a compliance guide for business — commercial email must be identified as an ad, carry a valid physical postal address and an opt-out honored within 10 business days; no exception for business-to-business email (read 2026-11-05)
- Google: Email sender guidelines — don't buy email addresses; above 5,000 messages a day to Gmail accounts, marketing messages need one-click unsubscribe (read 2026-11-05)