Two agents, one request: "be more direct."
The first agent begins sending correction notices. It rewrites your draft, flags every inconsistency, and appends a prioritised error list. This is directness — a principled directness that puts standards first and relational comfort second.
The second agent interrupts you. "I'll be direct," it says, "this plan won't work. I know where projects like this die, and this one dies here. Do you want me to walk through the actual reason?" This is also directness — a confrontational directness that puts present truth first and long-term comfort second.
Both responses are literally "direct." They feel like completely different people. If you only asked them to be "more direct," you had no way of predicting which kind you would get.
When words run out
AI agent prompt language has a fundamental vocabulary problem. The words we use — direct, creative, professional, friendly — borrow meaning from shared social experience in human conversation. An AI agent has no such shared history. It has only the word itself — and "direct" covers an enormous behavioural range. What prompt engineering cannot do, the Enneagram vocabulary can: it distinguishes motivations precisely, at the level of resolution that makes them actionable.
The Enneagram as precise language
Consider what "direct" actually means across different type patterns. Type 1's directness is principled — it identifies where something falls short of a standard, with evidence, process-oriented. Type 8's directness is confrontational — it names the thing no one else will say first, oriented toward power dynamics, sometimes creating friction deliberately to advance progress. Type 3's directness is efficiency-driven — it skips social scaffolding and goes straight to action items. Type 5's directness is analytical — information stripped of emotional packaging.
Same word, four distinct readings, four completely different experiences. When your system prompt says "stay direct," the model drifts between these interpretations based on whatever the last few hundred tokens implied. It is not being inconsistent — it is doing its best with an underspecified term.
“Vocabulary determines how precisely you can describe what you want. Without vocabulary for motivation, you are betting everything on the model's best guess at what 'friendly' means today.”
Once you share the vocabulary
When you and an agent share the Enneagram vocabulary, the quality of specification changes. You stop saying "be more direct" and hoping — you say "Type 8 directness, not Type 1." You stop saying "be more creative" — you say "Type 4 creativity (find what's being missed), not Type 7 creativity (generate more options)." The distinction moves from tone preference down to motivational architecture — and motivation is the layer that drives consistent behaviour.
These ideas — and 33 more like them — form the backbone of *The Complete Enneagram: From Human Personality to Agentic Soul*, just published on Amazon UK. **[Find it here →](https://amzn.eu/d/0fjWGvqR)**