The Problem
David built a career as an elite mental performance coach, working with ATP and WTA players who perform under some of the highest pressure in professional sports. But high-ticket coaching like his has always run into the same ceiling: it only scales as far as David's own calendar allows. A player who needs guidance at 11pm before a match, or between sessions when a specific mindset issue comes up, has nowhere to turn except generic sports psychology content that has nothing to do with David's actual methodology.
David had spent years developing a real, proven coaching philosophy, captured in his book, his course modules, and years of direct work with players, but none of it existed anywhere his athletes could actually access it in the moment they needed it. The gap wasn't a lack of expertise. It was that David's expertise lived entirely in his own head and calendar, with no way to extend it beyond the hours he could physically coach.
The Solution
We built The Sammel Method as a ring-fenced AI extension of David's actual coaching work, not a generic sports psychology chatbot. Every answer is retrieved directly from David's own intellectual property: his book, all fifteen course modules, and detailed coaching philosophy documents built collaboratively with David himself, capturing exactly how he diagnoses a player's mindset, selects the right framework, and calibrates challenge and support.
The system runs on OpenAI's models with heavily engineered instructions and retrieval limited strictly to David's own content. It cannot reach into the open internet or fall back on generic training data for coaching answers. If it's not in David's own methodology, the system says so and redirects the athlete back to David personally, a deliberate boundary, not a limitation. A multi-agent workflow handles the coaching conversation itself, player onboarding, and session continuity, so each athlete gets a personalized experience that remembers context across conversations.
The whole system lives inside David's existing digital education platform, behind an authenticated login, available to his athletes in any language, any time zone, any hour of the day. It doesn't replace David. It extends him, to the moments he can't physically be there.
Robert also manages the ad accounts driving new athletes to the platform, handling the technical side of Meta and Google campaigns, from ad set structure to conversion tracking, so growth stays measurable.
The Tech Stack
The Architecture Behind the Coach
Coaching Knowledge Base
RAG + Vector Store
Every answer is retrieved directly from David's own book, all fifteen course modules, and detailed coaching philosophy documents, never from generic sports psychology content.
Multi-Agent AI Workflow
GPT-4o, GPT-4o-mini, GPT-4.1-nano
Different AI models handle different jobs. Coaching conversations get full reasoning power, while summarization and utility tasks run on lighter, faster models, keeping the system efficient without sacrificing coaching quality.
Ring-Fenced Guardrails
Custom System Prompt Architecture
The AI cannot invent frameworks, reach into the open internet, or fall back on generic training data. If an answer isn't in David's own methodology, it says so and redirects the athlete back to David personally.
David's Coaching Persona, Encoded
Few-Shot Prompting + Contrastive Sets (RAG)
Built collaboratively with David through a deep-dive interview and refined iteratively, these documents capture his vocabulary, coaching rhythm, and philosophy so the AI sounds like him, not a generic assistant.
Custom Coaching App
Bubble.io + OpenAI ChatKit
A fully custom web app with authenticated login, player onboarding, and session tracking, so every athlete's experience is personal and continuous, not a one-off chat.
AI Orchestration Layer
OpenAI Agent Builder + Google Cloud Run MCP Server
A custom-built bridge connects the AI directly to the coaching app's database in real time, so every conversation, onboarding detail, and session picks up exactly where it left off.
The Results
A coach who never sleeps, never repeats himself, and never runs out of hours.
24/7
Coaching availability, with zero marginal cost per athlete
Any language
Coaching in whatever language the athlete speaks
Every conversation remembered
Session continuity, so context never resets between talks