| name | spike |
| description | Throwaway experiments to validate an idea before build. |
| version | 1.1.0 |
| author | Adapted from Hermes Agent (gsd-build/get-shit-done) |
| license | MIT |
| tags | ["spike","prototype","experiment","feasibility","throwaway","exploration","research","planning","mvp","proof-of-concept"] |
Spike
Use this skill when you want to feel out an idea before committing to a real build — validating feasibility, comparing approaches, or surfacing unknowns that no amount of research will answer. Spikes are disposable by design. Throw them away once they've paid their debt.
Load this when you hear things like "let me try this", "I want to see if X works", "spike this out", "before I commit to Y", "quick prototype of Z", "is this even possible?", or "compare A vs B".
When NOT to use this
- The answer is knowable from docs or reading code — just do research, don't build
- The work is production path — use an implementation plan instead
- The idea is already validated — jump straight to implementation
Core method
Every spike follows this loop:
decompose → research → build → verdict
↑__________________________________________↓
iterate on findings
1. Decompose
Break the user's idea into 2-5 independent feasibility questions. Each question is one spike. Present them as a table with Given/When/Then framing:
| # | Spike | Validates (Given/When/Then) | Risk |
|---|
| 001 | websocket-streaming | Given a WS connection, when LLM streams tokens, then client receives chunks < 100ms | High |
| 002a | pdf-parse-pdfjs | Given a multi-page PDF, when parsed with pdfjs, then structured text is extractable | Medium |
| 002b | pdf-parse-camelot | Given a multi-page PDF, when parsed with camelot, then structured text is extractable | Medium |
Spike types:
- standard — one approach answering one question
- comparison — same question, different approaches (shared number, letter suffix
a/b/c)
Good spike questions: specific feasibility with observable output.
Bad spike questions: too broad, no observable output, or just "read the docs about X".
Order by risk. The spike most likely to kill the idea runs first. No point prototyping the easy parts if the hard part doesn't work.
Skip decomposition only if the exact spike question is already known. Then take it as a single spike.
2. Align (for multi-spike ideas)
Present the spike table. Ask: "Build all in this order, or adjust?" Let adjustments happen before writing any code.
3. Research (per spike, before building)
Spikes are not research-free — you research enough to pick the right approach, then you build. Per spike:
-
Brief it. 2-3 sentences: what this spike is, why it matters, key risk.
-
Surface competing approaches if there's real choice:
| Approach | Tool/Library | Pros | Cons | Status |
|---|
| ... | ... | ... | ... | maintained / abandoned / beta |
-
Pick one. State why. If 2+ are credible, build quick variants within the spike.
-
Skip research for pure logic with no external dependencies.
Use web search and docs for the research step:
pip show websockets | grep Version
4. Build
One directory per spike. Keep it standalone.
spikes/
├── 001-websocket-streaming/
│ ├── README.md
│ └── main.py
├── 002a-pdf-parse-pdfjs/
│ ├── README.md
│ └── parse.js
└── 002b-pdf-parse-camelot/
├── README.md
└── parse.py
Bias toward something interactive. Spikes fail when the only output is a log line that says "it works." You want to feel the spike working. Default choices, in order of preference:
- A runnable CLI that takes input and prints observable output
- A minimal HTML page that demonstrates the behavior
- A small web server with one endpoint
- A unit test that exercises the question with recognizable assertions
Depth over speed. Never declare "it works" after one happy-path run. Test edge cases. Follow surprising findings. The verdict is only trustworthy when the investigation was honest.
Avoid unless the spike specifically requires it: complex package management, build tools/bundlers, Docker, env files, config systems. Hardcode everything — it's a spike.
Building one spike — a typical sequence:
mkdir -p spikes/001-websocket-streaming
cd spikes/001-websocket-streaming && python3 main.py
Parallel comparison spikes (002a / 002b) — when two approaches need real engineering, fan out with subagents (one per approach). Each returns its own verdict; you write the head-to-head.
5. Verdict
Each spike's README.md closes with:
## Verdict: VALIDATED | PARTIAL | INVALIDATED
### What worked
- ...
### What didn't
- ...
### Surprises
- ...
### Recommendation for the real build
- ...
VALIDATED = the core question was answered yes, with evidence.
PARTIAL = it works under constraints X, Y, Z — document them.
INVALIDATED = doesn't work, for this reason. This is a successful spike.
Comparison spikes
When two approaches answer the same question (002a / 002b), build them back to back, then do a head-to-head comparison at the end:
## Head-to-head: pdfjs vs camelot
| Dimension | pdfjs (002a) | camelot (002b) |
|-----------|--------------|----------------|
| Extraction quality | 9/10 structured | 7/10 table-only |
| Setup complexity | npm install, 1 line | pip + ghostscript |
| Perf on 100-page PDF | 3s | 18s |
| Handles rotated text | no | yes |
**Winner:** pdfjs for our use case. Camelot if we need table-first extraction later.
Frontier mode (picking what to spike next)
If spikes already exist and you're asked "what should I spike next?", walk the existing directories and look for:
- Integration risks — two validated spikes that touch the same resource but were tested independently
- Data handoffs — spike A's output was assumed compatible with spike B's input; never proven
- Gaps in the vision — capabilities assumed but unproven
- Alternative approaches — different angles for PARTIAL or INVALIDATED spikes
Propose 2-4 candidates as Given/When/Then.
Output
- Create
spikes/ in the repo root
- One dir per spike:
NNN-descriptive-name/
README.md per spike captures question, approach, results, verdict
- Keep the code throwaway — a spike that takes 2 days to "clean up for production" was a bad spike
Attribution
Adapted from the GSD (Get Shit Done) project's /gsd-spike workflow — MIT © 2025 Lex Christopherson (gsd-build/get-shit-done).