powerlift.ing

Purpose
- powerlift.ing is a static, client-only web app for creating a powerlifting program and sharing it as a single URL.
- There are no accounts and no backend API. The entire program state is encoded into the URL.

Creator / source
- Creator: James L. Cowan (@jameslcowan)
- Site: https://jameslcowan.com/
- Source code: https://github.com/jameslcowan/powerlift.ing

How sharing works (routing + state-in-URL)
- Default route format (hash): /#/p/<STATE>
- Optional “pretty” path format: /p/<STATE>
- The app uses history.replaceState() to keep the URL updated as the user edits.

Important: Do NOT change the URL/state contract
- Existing shared links depend on the exact encoding contract described below.

Encoding contract (v1)
- Program state is JSON, compressed using lz-string (compressToUint8Array), then base64url encoded.
- Decoding reverses this: base64url decode -> bytes -> lz-string decompressFromUint8Array -> JSON.parse.

Base64url details
- Replace '+' with '-', '/' with '_', and remove '=' padding.
- When decoding, restore padding to a multiple of 4.

Program state schema (v1)
{
  "v": 1,
  "u": "lb" | "kg",
  "c": [{ "n": "Meso 1" }, { "n": "Meso 2" }, ...],
  "weeks": [
    {
      "c": 0,
      "days": [
        {
          "label": "DAY 1 - MON",
          "rows": [
            {
              "ex": "Squat",
              "mode": "Paused",
              "sets": "3",
              "reps": "5",
              "load": "315",
              "pct": "80",
              "rpe": "8",
              "rest": "03:00"
            }
          ]
        }
      ]
    }
  ]
}

Example program JSON (minimal, 3 days/week, 1 week, kg)
{
  "v": 1,
  "u": "kg",
  "c": [{ "n": "Meso 1" }],
  "weeks": [
    {
      "c": 0,
      "days": [
        {
          "label": "DAY 1 - MON",
          "rows": [
            { "ex": "Squat", "mode": "", "sets": "4", "reps": "5", "load": "", "pct": "", "rpe": "7.5", "rest": "03:00" },
            { "ex": "Bench Press", "mode": "", "sets": "4", "reps": "6", "load": "", "pct": "", "rpe": "7.5", "rest": "02:30" }
          ]
        },
        {
          "label": "DAY 2 - WED",
          "rows": [
            { "ex": "Deadlift", "mode": "", "sets": "3", "reps": "5", "load": "", "pct": "", "rpe": "7.5", "rest": "03:30" },
            { "ex": "Overhead Press", "mode": "", "sets": "3", "reps": "8", "load": "", "pct": "", "rpe": "8", "rest": "02:00" }
          ]
        },
        {
          "label": "DAY 3 - FRI",
          "rows": [
            { "ex": "Squat", "mode": "Paused (2s)", "sets": "3", "reps": "4", "load": "", "pct": "", "rpe": "8", "rest": "03:00" },
            { "ex": "Bench Press", "mode": "Paused (1s)", "sets": "3", "reps": "5", "load": "", "pct": "", "rpe": "8", "rest": "02:30" }
          ]
        }
      ]
    }
  ]
}

Full example (multi-mesocycle, 4 weeks each, 4 days/week)
- See: https://powerlift.ing/ai.txt
- Or use: https://powerlift.ing/ai.html (click “Insert full example JSON” then “Generate link”)

Notes
- Keys are intentionally short for URL size.
- Numeric values are stored as strings in the state.

What AI agents can do with this
- Generate a program by producing valid JSON in the schema above.
- Encode/decode using the algorithm above (lz-string + base64url) to create a shareable /p/<STATE> link.
- Prefer generating “gym-friendly” plans (clear exercise names, reasonable sets/reps, rest times).

Indexing guidance
- The homepage should be indexable.
- Shared program links (/p/<STATE>) should not be indexed (they are user-generated and effectively infinite).