The AI-proposal tell
AI-generated marketing proposals get caught instantly because of nine telltale signs. Here's each, and how to fix them.
The 9 tells of AI-written proposals
1. Banned vocabulary
AI defaults to: synergy, leverage, robust, world-class, best-in-class, holistic, innovative, cutting-edge, ROI (without numbers).
Fix: ban these words from any AI prompt explicitly. AgencyPitch's master prompt does this; ChatGPT will revert without instruction.
2. No specific numbers
"Significant traffic increase" instead of "47% organic traffic growth in 6 months."
Fix: prompt the AI for specific numbers, even if you have to back-fill them yourself. Numbers earn trust.
3. Generic case studies
"We've worked with many clients in your industry."
Fix: prompt the AI to include a specific case study by name with specific metrics. Or: don't include a case study unless you have one.
4. Em-dash overuse
AI loves the em dash. A proposal with 8 em-dashes per page is suspicious.
Fix: use 1-2 per page max. Replace others with periods or commas.
5. Three-item lists everywhere
"strategic, tactical, and operational" / "clear, concise, and compelling" / "fast, reliable, and scalable"
Fix: vary list lengths. 2 items, 4 items, 5 items. Avoid the three-item rhythm.
6. "Comprehensive" overuse
AI uses "comprehensive" to mean "thorough." A proposal with 6 "comprehensives" is AI-tell.
Fix: replace each "comprehensive" with a specific word: complete, full-spectrum, end-to-end, exhaustive, audit-level.
7. No proper nouns
"the client" / "the team" / "the project" — generic refrains.
Fix: prompt the AI to replace pronouns with proper nouns. "Acme" / "the Acme team" / "the SEO retainer for Acme."
8. Empty intensifiers
"truly dedicated" / "really committed" / "absolutely passionate"
Fix: strike all of these. Strong sentences don't need them.
9. Closing with "thank you for considering"
The single most-AI-detected closing line in agency proposals.
Fix: close with a specific next step. "Sign and return by Friday. Kickoff call within 48 hours."
The fix: train the AI on your voice
The single most effective AI-proposal-writing improvement is brand voice training — feeding the AI 2-3 of your past best proposals so it learns your sentence rhythm, your vocabulary, your value framing.
The output then sounds like you wrote it, not like ChatGPT.
(AgencyPitch ships brand voice training out of the box. Generic AI tools require manual prompting each time.)
Banned-word checker
Before sending any AI-generated proposal, run it through a banned-word check. Use Find-and-Replace on:
- synergy
- leverage
- world-class
- best-in-class
- best-of-breed
- robust
- innovative
- cutting-edge
- holistic
- ROI (without specific %)
- comprehensive
- truly
- really
- absolutely
If you find any, rewrite the sentence specifically.
The 80/20 of human-vs-AI work
When using AI to draft a proposal, the workflow is:
- AI drafts (10 min): structure, sections, pricing scaffolding
- You edit (20 min): specific numbers, brand voice, banned-word strike, case study insertion
- AI polishes (5 min): grammar pass, formatting
Total: 35 min from blank page to send-ready. That's 4-6× faster than writing from scratch, with quality that doesn't read AI-written.
Try the AI that doesn't sound like AI
Run your latest proposal through our free audit tool — get a 0-100 score and specific fixes if it reads AI-written.