Design a portable prompt-pack file format (.promptkit)

[Cryptoteep]

Context

Right now prompts are TypeScript modules. That's great for developers but bad for two use cases:

1. Sharing — you can't easily drop a prompt into someone else's project without matching deps.
2. Non-developers — prompt engineers who don't write TS can't author prompts.

Proposal (RFC)

Define a portable prompt-pack format: a single YAML or JSON file describing one or more prompts, their inputs, templates, and eval cases.

# sentiment.promptkit.yaml
pack: 1
prompts:
  - name: classify-sentiment
    version: 1.1.0
    description: Classify sentiment into N labels.
    input:
      text: { type: string, required: true }
      labels:
        type: array
        items: { type: string }
        default: [positive, negative, neutral]
    template: |
      Classify the sentiment of: "{{text}}"
      Labels: {{labels}}
      ->

Then:

• promptkit load sentiment.promptkit.yaml → returns PromptDefinition[].
• promptkit run sentiment.promptkit.yaml#classify-sentiment ….
• Export from TS: import { loadPack } from 'promptkit/pack'.

Open questions

• YAML or JSON only? (YAML is nicer for multi-line templates; adds a dep.)
• How to express validate declaratively? Limited subset, or validate: { minLength: 1 } style?
• Versioning of the pack format itself.
• Should packs be installable from a registry URL?

Acceptance

• Format spec written in docs/pack-format.md.
• loadPack() loader + tests.
• promptkit load command.
• At least one example pack.

Looking for feedback on the format before implementation. Please comment with use cases!

/label "enhancement" "area:loader" "help wanted"