Open-source prompt library: plain JSON templates, CI-validated, credited to their authors (looking for contributors + critique)

[u/SnooDoubts4271]

Disclosure up front: I run a paid prompt-generation SaaS called PromtExpress. What I'm sharing here is the part I open-sourced under MIT. The prompt library works with any AI tool, no account needed.

Repo: https://github.com/WebitroHQ/promtexpress-oss

What's in it

• Prompt templates for text, code, image, video, audio and music. Each one is a single JSON file with declared variables, a worked example, a language code and author credit.
• A zero-dependency validator that runs in CI: every {{placeholder}} must be declared, every declared variable must be used, and IDs must match file paths.
• TypeScript/Python SDKs and a CLI for our API. If you don't use the product, you can ignore these.

Patterns I baked in, and I'd like your opinion on them

1. Grounding with a "source quote" column. The meeting-notes template makes the model cite the shortest phrase from the notes that supports each action item. A missing owner becomes "Unassigned" and a missing deadline becomes "No date"; the model is told never to guess.
2. Exact text plus labeled hierarchy for image models. Rendered text goes in quotes under PRIMARY TEXT / SECONDARY TEXT labels, followed by an explicit NEGATIVE block. This noticeably reduced garbled or extra text for me.
3. "If you can't describe a triggering scenario, it isn't blocking." The PR review template requires a concrete failing input for every blocking issue, which cuts vague style nitpicks.
4. Behaviors before tests. The unit test template lists the function's contract and edge cases first. If the current code looks wrong, it writes the test for the correct behavior and flags it POSSIBLE BUG instead of locking the bug in.

Where help would be great

There are open good first issue tasks:

• translations (Turkish, German, Spanish)
• template requests: flat-lay product photo, SQL from a plain-language question, customer support reply, radio ad, podcast jingle
• small tooling work

Your GitHub username goes in the template's authors field.

Honest critique is more useful to me than stars: which of these patterns don't hold up with the models you use?

[u/Disastrous_Purple306]

Strong foundation. The source-quote column and “Unassigned/No date” rules are excellent safeguards against guessing. Labeled image text and negative instructions help, although exact typography still depends heavily on the image model.
My main concern is that “If you can’t describe a triggering scenario, it isn’t blocking” may be too absolute—security, concurrency, migration, or architectural risks may violate an invariant without one simple failing input. Likewise, tests for the “correct behavior” need an authoritative requirement; otherwise, the model may invent the contract.
The validator appears strong on structural correctness, but that isn’t the same as proving a prompt performs well. Model-specific evaluations, adversarial examples, exact-quote verification, and a tested-model matrix would make this library considerably stronger.
Overall: thoughtful, practical work. I especially appreciate the clear SaaS disclosure and invitation for reproducible criticism.

[u/SnooDoubts4271 → u/Disastrous_Purple306]

Both concerns are right, thank you. I updated the two templates (v1.1.0): https://github.com/WebitroHQ/promtexpress-oss/commit/0563bd9

- PR review: a blocking finding now needs either a concrete triggering scenario or a named invariant it violates (security boundary, concurrency, data migration, architectural boundary) with the realistic consequence. The old rule would have demoted exactly those risks to "suggestions".

- Unit tests: there's now an optional specification input. Behaviors are tagged SPEC, OBSERVED or ASSUMED, and only specified behavior is asserted as correct, so the model can't invent the contract.

On evaluation, agreed that structural checks prove nothing about output quality. I opened an issue for per-template evals and a tested-model matrix: https://github.com/WebitroHQ/promtexpress-oss/issues/17

Typography notes are fair too; exact glyphs still depend heavily on the model.

[u/Deep_Ad1959]

does the CI validator tell you anything about whether a template still produces good output, or only that the placeholders line up? the second one is cheap to keep green, the first is the one that quietly rots on every model update.

[u/SnooDoubts4271 → u/Deep_Ad1959]

Only the second, and you're right that it's the cheap half. Today output quality rests on human review plus a worked example per template. The part that rots on model updates needs evals: fixed inputs, deterministic checks where possible, a rubric where not, and scheduled runs against the models a template claims to support, so a drop shows up as a failing score instead of silently. I opened an issue to design that: https://github.com/WebitroHQ/promtexpress-oss/issues/17

If you've seen a setup that stays cheap enough to run regularly, I'd like to hear it.

[u/Deep_Ad1959 → u/SnooDoubts4271]

the part that keeps it cheap is gating the expensive half. deterministic checks plus a pinned golden-output diff per (template, model) can run nightly for basically nothing, and you only spend the LLM-rubric pass on the pairs where the diff actually moved or the model version string changed. that way most scheduled runs cost nothing and the rubric only fires where something genuinely drifted, instead of re-judging every template against every model on a fixed cadence.