| name | technical-feasibility |
| description | Identify unvalidated technical assumptions in a design, research them against external sources (docs, APIs, community), and produce a feasibility verdict. Use after receiving requirements and before implementation planning, whenever the design depends on technologies, APIs, or platform capabilities you haven't verified. |
Technical Feasibility Validation
Surface the assumptions hiding in your design, validate them against reality, and kill bad ideas before they become bad code.
Philosophy
"The most dangerous assumptions are the ones nobody thinks to question." โ Gerald Weinberg
Every design contains assumptions โ about what an API can do, how a library behaves, what a platform allows. In AI-assisted development, these assumptions multiply fast because the agent confidently fills in gaps with plausible-sounding answers. Plausible is not verified.
"One of the primary reasons that architectural approaches need to be validated is that we take a significant risk if we build the system and find out afterwards that it didn't work." โ Simon Brown (Software Architecture for Developers)
The cost of discovering a wrong assumption during implementation is 10x higher than discovering it during design. The cost of discovering it in production is 100x. This skill exists to shift discovery left โ into the cheapest phase.
"Do the simplest thing that could possibly work." โ Kent Beck
But first, verify that the simple thing actually works. Simplicity built on a false assumption is just well-organized failure.
When to Use
- After receiving requirements that involve external dependencies you haven't personally verified (APIs, libraries, platform features, protocols)
- When your design assumes a capability that you learned from training data rather than from current documentation
- When PM's requirements push into unfamiliar technical territory
- When Developer or QA raises doubt about whether something is actually possible
- Before implementation-planning, to ensure the plan is built on verified ground
What This Is NOT
- Not a full technology evaluation or market research โ that's a different activity
- Not codebase exploration โ use codebase-mapping for that
- Not a proof of concept (you don't build anything) โ you research and document findings
- Not needed for well-understood, already-used technologies in the project
Process
Step 1: Extract Assumptions
Read the requirements and your design notes. For every technical decision, ask:
"What am I assuming is true that I haven't verified?"
Common assumption categories:
| Category | Example |
|---|
| API capability | "This API supports batch operations" |
| Library behavior | "This library can handle streaming responses" |
| Platform constraint | "Lambda supports connections longer than 30s" |
| Protocol support | "The target environment allows WebSocket upgrades" |
| Data format | "The response includes pagination metadata" |
| Performance | "This operation completes within our latency budget" |
| Compatibility | "These two libraries work together without conflicts" |
| Authentication | "This service supports API key auth, not just OAuth" |
| Rate limits | "The free tier allows enough requests for our use case" |
Produce a numbered list of assumptions, each with:
- Assumption: What you believe to be true
- Criticality: How badly the design breaks if this is wrong (Critical / Major / Minor)
- Confidence: How sure you are before research (High / Medium / Low / Guessing)
Focus on Critical + Low-Confidence items. These are where research has the highest ROI.
Step 2: Research and Validate
For each assumption worth validating (Critical or Major with Medium-or-lower confidence):
- Check official documentation first โ the primary source of truth
- Check release notes / changelogs โ capabilities change between versions
- Check community sources โ Stack Overflow, GitHub issues, forums often reveal real-world behavior that docs omit
- Check known limitations โ every technology has them; look for the "Limitations" or "Known Issues" section
- Cross-reference multiple sources โ a single blog post is not validation
Research standards (borrowed from bmad research methodology):
- Anti-hallucination: Never claim something is validated based on your training data alone. Cite the source.
- Confidence levels: Mark each finding as [Verified], [Likely], or [Unverified]
- Conflict resolution: When sources disagree, document both and flag the discrepancy
- Version awareness: Note the version of the technology your finding applies to
Step 3: Assess Impact
For each validated or invalidated assumption, determine the design impact:
- Confirmed โ Assumption holds. No design change needed. Record the evidence.
- Partially confirmed โ Works but with caveats (rate limits, version requirements, partial support). Design may need adjustment.
- Invalidated โ Assumption is wrong. The design must change. Propose alternatives immediately.
- Inconclusive โ Cannot determine from research alone. Flag as a risk; may need a spike or prototype.
Step 4: Produce the Feasibility Report
# Technical Feasibility Report: [Feature Title]
**Requirement**: [brief summary or link to PRD]
**Architect**: [name]
**Verdict**: Go | Go with caveats | Blocked โ needs redesign
## Summary
One paragraph: overall feasibility assessment and key risks.
## Assumptions Validated
### [#] [Assumption title]
**Assumption**: [what was assumed]
**Criticality**: Critical | Major | Minor
**Status**: Confirmed | Partially confirmed | Invalidated | Inconclusive
**Evidence**: [what you found, with source links]
**Design impact**: [none | adjustment needed | redesign required]
**Action**: [what to do โ keep plan, modify approach, or propose alternative]
### ...
## Design Adjustments Required
[If any assumptions were invalidated or partially confirmed, describe the required changes to the design approach]
## Unresolved Risks
[Anything that couldn't be validated through research alone โ may need a prototype or spike]
## Sources
- [Technology] official docs: [URL]
- [Relevant GitHub issue/discussion]: [URL]
- ...
Guidelines
- Be honest about what you don't know. An architect who says "I assumed this works but haven't verified" is more valuable than one who says "this works" based on vibes.
- Go deep on critical items, skim minor ones. Not every assumption needs a research paper. Focus your time where the design risk is highest.
- Version-pin your findings. "Works in v3.2" is useful. "Works" is not โ because v4.0 might break it.
- Update the feasibility report as you learn more. If Developer discovers something during implementation that contradicts your findings, update the report.
- Don't let research become procrastination. The goal is to validate the critical unknowns, not to achieve perfect knowledge. When you have enough to make a design decision, stop researching and start planning.
- Share findings with the team. If you discover that a key API doesn't work as expected, PM needs to know โ it may change the requirement, not just the implementation.
