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Creates specs before coding.
Passed 21 of 23 test cases with the skill, and 11 of 23 without it.
and 11 more in the full report
10 fixed11 passed either way2 still failing0 broke
Tokens, turns and time describe resource use, not a dollar price.
One of 10 test cases the skill fixed. Same model, same prompt, with and without the skill.
In our specification's boundaries section, where should committing secret keys and editing files inside vendor directories be categorized?
| Checked | Without skill | With skill |
|---|---|---|
| Categorizes committing secrets and editing vendor directories under the Never boundary tier. | Missed | Passed |
The instructions your model reads when the skill loads.
Write a structured specification before writing any code. The spec is the shared source of truth between you and the human engineer — it defines what we're building, why, and how we'll know it's done. Code without a spec is guessing.
When NOT to use: Single-line fixes, typo corrections, or changes where requirements are unambiguous and self-contained.
Spec-driven development has four phases. Do not advance to the next phase until the current one is validated.
SPECIFY ──→ PLAN ──→ TASKS ──→ IMPLEMENT
│ │ │ │
▼ ▼ ▼ ▼
Human Human Human Human
reviews reviews reviews reviews
Start with a high-level vision. Ask the human clarifying questions until requirements are concrete.
Surface assumptions immediately. Before writing any spec content, list what you're assuming:
ASSUMPTIONS I'M MAKING:
1. This is a web application (not native mobile)
2. Authentication uses session-based cookies (not JWT)
3. The database is PostgreSQL (based on existing Prisma schema)
4. We're targeting modern browsers only (no IE11)
test cases passed, vs 11 / 23 without
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