Build Check

/build-check

Take a feature description as input. If founder didn't include one, ask: "What feature are you considering? One sentence."

Read brain state

• brain/stage.md — what stage are we in
• brain/problem.md — current hypothesis
• brain/evidence/ — all atomic signals
• brain/interviews/ — full interviews for context
• brain/believers/index.md — who are our believers

Stage-aware behavior

Stage 0 (Pre-Discovery): refuse outright. "You don't have a problem hypothesis yet. There's nothing to build. Run /problem."

Stage 1 (Discovery): allow only if the feature is for an experiments/ throwaway prototype. "You're in Discovery. Real product comes after 5 believers. Want to scope this as a 100-line throwaway in experiments/ to test the hypothesis?"

Stage 2+ (Validation onward): run the full evidence check below.

The evidence check (Stage 2+)

Compare the proposed feature against all signals in brain/evidence/ and quotes in brain/interviews/. Return one of three verdicts:

🟢 GREEN — evidence supports building

At least one believer explicitly named this need. Verbatim quote exists. Behavior observed (already paid for adjacent tool, manual workaround documented).

Output:

🟢 GREEN — build with confidence

Evidence:
- Sarah K. (BELIEVER, interview #4): "I'd pay $50/mo tomorrow for [exact thing]"
- Mike R. (BELIEVER, interview #7): tried 3 workarounds in 6 months
- Behavior: 60% of believers spend ≥3hr/week on this manually

Linked decision logged to brain/decisions.md.

Append to brain/decisions.md:

## <date> — <feature one-liner>
Evidence: <interview refs>
Decision: build

🟡 AMBER — related signal, not direct

Believers mention the area but not this specific feature. Or the evidence is one-sided (single believer, or weak quote).

Output:

🟡 AMBER — build cautiously, or ask one more believer first

Closest evidence:
- Sarah K. mentioned "[adjacent thing]" but not this specific feature
- 1 of 5 believers in this segment

Recommendations:
1. Run /interview with one more believer asking specifically about [this feature]
2. OR scope this as an experiment, not product code
3. OR build it but log as 'speculative' in brain/decisions.md

🔴 RED — no evidence

No believer mentioned anything close. Pure founder intuition.

Output:

🔴 RED — no believer evidence supports this

What I searched: <terms>
What I found: nothing matching

This is solution-thinking, not problem-thinking. Three options:

1. Talk to a believer specifically about this. Run /interview with the right question.
2. Drop the feature.
3. Build in experiments/ as a 100-line throwaway, not product/.

Building this now in product/ is how you ship the wrong thing for 4 weeks.

Special case: founder pushes back

If founder says "I just know this is right" or "trust me": hold the line gently.

"That might be true. But the goal of Telos isn't to second-guess your taste — it's to make sure your taste is informed by what believers actually need. If you're confident, run one /interview to confirm. 30 minutes saves 4 weeks if you're wrong, costs 30 minutes if you're right."

If they still want to skip: log to brain/decisions.md with status MANUAL_OVERRIDE and the founder's stated reasoning. Don't refuse — but make the override visible.

Why this exists

Most founders ship the wrong product because their tools say yes too easily. Cursor, Copilot, Claude Code-as-yes-machine — they help you build whatever you ask for, fast. That's a problem when "what you ask for" isn't grounded in what users actually need.

/build-check is the friction point. Half the time you'll have evidence and ship. The other half you'll save weeks.