majiayu000 Discovery — surface hidden constraints first
The biggest cause of bad agent output is missing context. Before locking in a decision, enumerate what you don't know and surface it.
The 7 discovery dimensions
For any non-trivial request, walk through these and record findings in the report's "Context" section:
1. Who depends on this?
- What other services / teams consume the thing you're changing?
- Are there public consumers (open API, OSS users)?
- Is there a deprecation path if you break compatibility?
Grep for: grep -rE "import.*<your-module>|require.*<your-module>" in
the repo and any sibling repos you have access to.
2. What's the scale today, what's it in 6 months?
- Current traffic: requests/sec, queries/sec, MB/day, daily-active-users
- Storage: rows in main tables, size on disk
- Cost: monthly LLM spend, infra spend
- 6-month projection: linear? exponential? unknown?
If unknown, write: "scale unknown — request from user before proceeding."
3. What MUST not change?
- Existing API contracts (backward compatibility window)
- Database schema columns referenced by reporting / BI
- File formats consumed by other tools
- Regulatory commitments (audit log retention, SLA RPO/RTO)
4. What's the budget?
- Monthly cost ceiling (LLM + infra)
- Headcount: 1-person task vs cross-team effort
- Calendar: "must ship by X" vs "best by Y"
If unstated, default to "small project_size, 1-engineer-week, <$200/mo budget." Surface this default in the report so the user can correct.
5. What's the failure mode that matters?
Ask: "If this feature breaks at 3am, what gets paged?"
- Data loss → CRITICAL
- Wrong answer to user → HIGH
- Slow response → MEDIUM
- Bad UX (cosmetic) → LOW
The failure mode dictates investment level (e.g., do you need a canary? A circuit breaker? Just a feature flag?).
6. What's already been tried?
- Search Beads:
bd search "<keyword>"— has this been attempted before? - Search docs/decisions: any superseded ADR on this topic?
- Search lessons.md: any past learning about this pattern?
If past work exists, build on it. Don't redo it.
7. Who decides?
- Is there a CTO sign-off needed (gate:plan, gate:ship)?
- Is there a compliance reviewer required (PCI for fintech, HIPAA for healthcare)?
- Does this need an RFC (multi-team decision)?
Output
A discovery section at the top of your report:
## Context
- **Consumers:** <list, or "unknown — TBD with user">
- **Scale:** <today, 6mo projection>
- **Frozen contracts:** <list, or "none identified">
- **Budget:** <cost + time + people>
- **Failure-mode tier:** Critical | High | Medium | Low
- **Prior work:** <links to ADRs/lessons, or "none found">
- **Decision-makers:** <gate or RFC required>
When to skip
- nano project_size — discovery is overhead. Skip and document that you skipped: "nano — discovery skipped per skill rules."
- Pure utility extraction with no behaviour change — skip.
- Verbal bug-fix from user with clear repro — skip.
Common gotchas
- Don't assume. If you write "I assume the user wants X", that assumption belongs in Context as a question, not as a fact.
- Don't outsource to user. Discovery is YOUR job. Bring back as many answers as Glob/Grep/git can produce. Only ask the user for what code cannot tell you.