Files
AILang/experiments/2026-05-12-cross-model-authoring/qwen_ablation.py
T
Brummel da99ebaba8 experiment(cma): ablation finds WHY Qwen fails at Form-A — two distinct walls (refs #68)
Try-and-error ablation, minimal few-shot context, single shot per level, a
ladder L0 (fn returns 42) to L7 (full SMA). Two ladders: base few-shot that
only destructures, then one that also constructs (term-ctor).

Finding: Qwen is NOT generally incapable. With minimal correct context it
writes 6/8 tasks green, including ADTs, match, recursive fns, and Series use.
The failures are two specific walls:

- Wall 1 (cheap): unfamiliar constructs. It built lists with (app Cons ...) —
  calling the ctor like a function — because it had only seen match, never
  term-ctor. Adding ONE term-ctor example flipped L3 and L5 to green and
  removed the Cons error. The model generalises a construct from one example.

- Wall 2 (hard): paren/nesting discipline at depth. The two that stay red
  (L4, L7) fail purely on bracketing, not knowledge. In L4 the recursive
  function is flawless; main closes a 4x-nested term-ctor value one paren
  early so the let body slides inside it — total paren count is BALANCED
  (43/43), the parens are just misplaced. Green/red tracks nesting depth, not
  feature. Examples do not fix it. This is the same weakness the full-SMA
  probes hit (run 2 had correct logic, died on brackets; run 3's long context
  tipped it into a seq-repetition loop).

Takeaway: the bottleneck is the fully-parenthesised surface at depth, not the
semantics. Natural next test: the .ail.json authoring form, which removes
human paren-counting. Driver qwen_ablation.py; ladders in qwen-ablation-min.md
and qwen-ablation-ctor.md; synthesis in qwen-ablation.md.
2026-06-02 18:09:31 +02:00

142 lines
7.1 KiB
Python

#!/usr/bin/env python3
"""Ablation probe: WHY does Qwen3-Coder-Next fail at AILang Form-A?
Try-and-error from a minimum upward. A ladder of tasks of increasing
complexity (L0 trivial → L7 full SMA), each run INDEPENDENTLY: fresh,
minimal few-shot context, single shot (no retry, no dialog accumulation —
prior probes showed retries don't converge and long context degenerates).
The first level that breaks localises the wall.
Reads $IONOS_API_TOKEN (never printed). Live IONOS — run with consent.
"""
from __future__ import annotations
import json, os, re, subprocess, urllib.request
from pathlib import Path
ENDPOINT = "https://openai.inference.de-txl.ionos.com/v1/chat/completions"
MODEL = "Qwen/Qwen3-Coder-Next"
REPO = Path(__file__).resolve().parents[2]
AIL = os.environ.get("AIL_BIN", str(REPO / "target/debug/ail"))
DOC = REPO / "experiments/2026-05-12-cross-model-authoring/qwen-ablation-ctor.md"
DEMO_A = """(module demo_a
(fn double
(type (fn-type (params (own (con Int))) (ret (own (con Int)))))
(params x)
(body (app + x x)))
(fn main
(type (fn-type (params) (ret (own (con Unit))) (effects IO)))
(params)
(body (seq (app print (app double 21)) (do io/print_str "\\n")))))"""
DEMO_B = """(module demo_b
(data IntList (ctor Nil) (ctor Cons (con Int) (con IntList)))
(fn sum
(type (fn-type (params (own (con IntList))) (ret (own (con Int)))))
(params xs)
(body
(match xs
(case (pat-ctor Nil) 0)
(case (pat-ctor Cons h t) (app + h (app sum t))))))
(fn main
(type (fn-type (params) (ret (own (con Unit))) (effects IO)))
(params)
(body
(let xs (term-ctor IntList Cons 1 (term-ctor IntList Cons 2 (term-ctor IntList Nil)))
(seq (app print (app sum xs)) (do io/print_str "\\n"))))))"""
DEMO_S = """(module demo_s
(fn main
(type (fn-type (params) (ret (own (con Unit))) (effects IO)))
(params)
(body
(let s (new Series (con Float) 3)
(let s2 (app Series.push s 1.0)
(let s3 (app Series.push s2 2.0)
(seq (app print (app Series.len s3)) (do io/print_str "\\n"))))))))"""
INTRO = ("AILang is a fully-parenthesised S-expression language (\"Form-A\"). "
"Study these complete, valid example modules, then write the requested "
"module. Return ONLY the AILang source for the module — no prose, no "
"markdown fences.\n\n")
BASE = INTRO + "Example 1:\n" + DEMO_A + "\n\nExample 2:\n" + DEMO_B + "\n"
SERIES = (BASE + "\nExample 3 (uses the Series ring-buffer library — "
"`(new Series (con Float) N)` allocates one of capacity N; "
"`Series.push : (own (Series a)) (own a) -> (own (Series a))` appends "
"and returns the new series; `Series.at : (borrow (Series a)) (own Int) "
"-> (own a)` reads index i back from newest (0 = newest); "
"`Series.len`/`Series.total_count : (borrow (Series a)) -> (own Int)`):\n"
+ DEMO_S + "\n")
SMA_OUT = "3.0\n5.33333\n5.66667\n5.33333\n"
SMA_TASK = ("Write a module `m` computing a simple moving average, window 3, over "
"the float stream 1.0, 5.0, 3.0, 8.0, 6.0, 2.0 using the Series library: "
"create a Float Series lookback 3, push each value in turn, and after each "
"push once at least 3 values have been pushed, print the average of the "
"most recent 3 (their sum / 3.0) on its own line. Expected:\n" + SMA_OUT)
# (id, context, task, expected_stdout_or_None[=check-only])
STAGES = [
("L0_const", BASE, "Write a module `m` with a function `answer` taking no parameters that returns the Int 42.", None),
("L1_arith", BASE, "Write a module `m` with a function `triple` taking one Int parameter, returning it multiplied by 3.", None),
("L2_print", BASE, "Write a module `m` whose `main` prints the Int 7 on its own line.", "7\n"),
("L3_adt", BASE, "Write a module `m` with an ADT `Light` (ctors Red, Green) and a function `code` returning Int 0 for Red and 1 for Green via match.", None),
("L4_rec", BASE, "Write a module `m` with an IntList ADT (Nil/Cons), a function `length` counting elements by recursion, and a `main` that prints the length of the list [1,2,3] on its own line.", "3\n"),
("L5_series_len", SERIES, "Write a module `m` using the Series library: create a Float Series lookback 3, push 1.0 then 2.0 then 3.0, then print its Series.len on its own line.", "3\n"),
("L6_series_at", SERIES, "Write a module `m` using the Series library: create a Float Series lookback 3, push 1.0 then 2.0 then 3.0, then print (Series.at on index 0, the newest) on its own line.", "3.0\n"),
("L7_sma", SERIES, SMA_TASK, SMA_OUT),
]
def call(system, task):
body = json.dumps({"model": MODEL, "temperature": 0.2, "max_tokens": 1500,
"messages": [{"role":"system","content":system},{"role":"user","content":task}]}).encode()
req = urllib.request.Request(ENDPOINT, data=body, headers={
"Authorization": f"Bearer {os.environ['IONOS_API_TOKEN']}", "Content-Type":"application/json"})
with urllib.request.urlopen(req, timeout=120) as r:
d = json.loads(r.read())
return d["choices"][0]["message"]["content"], d.get("usage", {})
def extract(resp):
m = re.search(r"```(?:[a-zA-Z]*)?\n(.*?)```", resp, re.S)
code = m.group(1) if m else resp
i = code.find("(module")
return code[i:].strip() if i >= 0 else code.strip()
def evaluate(code, expected):
m = re.search(r"\(module\s+([A-Za-z_][A-Za-z0-9_]*)", code)
name = m.group(1) if m else "m"
f = Path(f"/tmp/abl/{name}.ail"); f.parent.mkdir(exist_ok=True); f.write_text(code+"\n")
chk = subprocess.run([AIL,"check",str(f)], capture_output=True, text=True)
if chk.returncode != 0: return "check", (chk.stderr or chk.stdout).strip()
if expected is None: return "green", "(check-only)"
run = subprocess.run([AIL,"run",str(f)], capture_output=True, text=True)
if run.returncode != 0: return "run", (run.stderr or run.stdout).strip()
if run.stdout != expected: return "output", f"got {run.stdout!r}, expected {expected!r}"
return "green", run.stdout
def main():
log = ["# Qwen3-Coder-Next ablation — where does Form-A authoring break?\n",
f"**Model:** {MODEL}; single-shot per level; minimal few-shot context.\n",
"Each level is independent (fresh context, one call, no retry).\n", "---\n"]
summary = []
for sid, ctx, task, exp in STAGES:
resp, usage = call(ctx, task)
code = extract(resp)
stage, fb = evaluate(code, exp)
ok = stage == "green"
mark = "✅ green" if ok else f"❌ {stage}"
summary.append((sid, mark))
print(f"{sid}: {mark}")
log += [f"## {sid}{mark}",
f"\nctx={'BASE' if ctx is BASE else 'SERIES'} tokens: "
f"prompt={usage.get('prompt_tokens','?')} completion={usage.get('completion_tokens','?')}\n",
"```\n"+code+"\n```\n",
("" if ok else f"**`ail {stage}`:**\n```\n{fb[:800]}\n```\n")]
log += ["\n---\n## Ladder\n"] + [f"- {s}: {m}" for s,m in summary]
DOC.write_text("\n".join(log))
print("doc →", DOC)
if __name__ == "__main__":
main()