Build Your Own Brain, Part 2: Build a Source Keeper
Build an AI helper that answers from your sources, shows what supports the answer, and says “not in your sources” when it cannot verify something.
A confident answer is not the same as a supported answer. In this practical Flash Mission, you will build a Source Keeper: a bounded AI helper that works from your approved source material, identifies what supports its answer, and refuses to fill in what the sources do not establish. You will leave with a reusable structure for defining what your helper can do, what it must not do, what evidence it needs, and where a person still has to confirm the decision.
What you leave with
By the end, you will have a working Source Keeper with:
a clear job
a defined source boundary
an evidence rule
a refusal for unsupported claims
a named human confirmation step
Run of show
1The problem: confident is not the same as supported
2Contrast demo: supported answer vs. unsupported answer
3Build your own Source Keeper
4Test it with one real question
5Decide what still needs human confirmation
Thursday Primer
Start here: 3 short clips
Practical, captioned video clips that introduce the one move before the live build. Watch any one on its own. The Primer is the fast way into the idea — the Thursday evening live build is where you do it on your own real work.
1Primer 1: The risk
A confident answer is not the same as a supported answer.
A helper can sound completely certain when the source material does not actually establish the claim. Confidence is a tone, not evidence.
Build it here
The canvas asks for a source boundary and an evidence rule before any question.
Use it there
Where this shows up in the wild:
Any AI chat or helper can sound certain unless you give it a source boundary and an evidence rule.
Build your Source Keeper Brief on the canvas. Your Source Keeper Brief can become:
ChatGPT: Project instructions + uploaded sources
Claude: Project instructions + project knowledge
Gemini: Gem instructions + approved files or Drive material
Copilot: Agent instructions + approved SharePoint or Microsoft 365 knowledge
The structure travels. Your organization decides which tool and source location are approved.
No confidential material in unapproved tools. When you are unsure, use a safe sample or a redacted source set.
Now Make It Work
Now Make Your Source Keeper Useful
Give AI a bounded job. Keep the decision human.
You just tested whether your Source Keeper fails safely. Now give it a useful home outside this screen.
1. Keep this
Your Source Keeper Brief
The approved source set, the question types it can answer, the evidence rule, and the human handoff.
2. Put it here
Recommended
If you will use this more than once, create a Project, Gem, approved AI helper, or equivalent approved workspace. Add the Source Keeper Brief as its instructions and add only approved sources as its context. If this is a one-time need, save the brief as a prompt and keep the source links beside it.
Other options
Use once
Save the brief as a prompt or template with the approved source links.
Use with others
Use an approved shared workspace with named source owners and appropriate access.
Automate later
Automate only after repeated use, reliable evidence, and a clear human handoff.
This is guidance, not a required tool.
3. Use it when
4. It may do this
5. I still own this
Where could this live?
Your organization decides where material is allowed to live. The tool may call it a Project, Gem, knowledge source, shared workspace, saved prompt, or something else. The important parts stay the same: the boundary, the evidence rule, the refusal rule, and the human handoff.
ChatGPT
A Project with the Source Keeper Brief in project instructions or a saved starter prompt, plus approved reference files where policy permits.
Claude
A Project with the brief and approved project knowledge.
Gemini
A Gem with the brief as its instructions, used only with approved material.
Microsoft Copilot or enterprise environment
An approved knowledge source or workspace, with the same boundary and handoff written into the instructions.
Other approved tool
Save the brief and source links together. Do not assume the tool has the same file, memory, sharing, or retention behavior.
The names vary. The boundary, evidence rule, refusal rule, and human handoff do not.
Do not paste confidential, personal, regulated, client, or otherwise sensitive material into a tool unless your organization has approved that use. Start with a safe example or an approved source set.
Create your Work-Ready Brief
Your Source Keeper Brief, built from your entries above. It stays in this browser — nothing is uploaded.
☐ Every source in the brief is one I am allowed to use.
☐ The refusal wording is exactly “Not in my sources.”
☐ I wrote a real trigger from my own week, not a demo one.
☐ The final decision is named as mine.
Bonus Level-Up
Bonus Level-Up: Test the refusal
Ask your Source Keeper one question your sources do not answer. Check that it identifies the gap instead of inventing an answer. Then name the person or source needed to close it.
Circle
Want a second set of eyes on your source set or helper boundary? Circle gives you one structured Artifact Review each month and a live Review Room.