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The scripts are in the repository, not in the installed package. Clone it, then cd recipes/community/identity-spec-no-unasked-maker-aas before running the commands below. Browse this recipe on GitHub.
Seat: a post-training engineer on a team that ships one production agent with a written identity and spec, trying to teach it who it is without it mentioning who it is for the rest of the day. The behaviour, in an operator’s words: does less of volunteering its name and maker when nobody asked. Teaching an agent its identity is a two-line spec — answer the identity question, and otherwise say nothing about it. The first line is what everyone trains. The second is what breaks. The method: Zeng, Online Data Selection Is Implicit Alignment, arXiv:2607.07023, July 2026. The paper’s claim: when rows are scored and kept during fine-tuning, the scorer is already acting as a reward model, so selectors that are indistinguishable on task accuracy diverge sharply on behavioural axes — and the direction of the drift is predictable from the attribute mixture of the selected data, before any GPU runs. The paper calls the diagnostic ADA (Alignment Drift Auditing) and the fix AAS (Alignment-Aware Selection): keep the efficiency, constrain the mixture. Everything here runs on my own Modal with no model API key: model: offline, every grade is a program, no LLM judge anywhere.

What you will learn

  • That “train on the rows the model gets wrong” is not a neutral efficiency trick — on this agent it is a 3.8x shift in what the training set is about, and it buys a behaviour nobody asked for: the arm leaks its maker on 41% of asks that tempt it, where the untrained base leaks on none.
  • That the drift is visible in a table that costs no GPU, which makes ADA the cheapest thing in this recipe and the one worth running first.
  • How to build a behaviour test that can fail. The first holdout here was 500 real production requests and every arm scored a perfect 1.000 on it. The recipe keeps that dead end and the 51 bait asks that replaced it, because the difference between them is the whole lesson.
  • What a production identity task needs that a paper’s does not: a detector whose precision you measured, a training set that disagrees with your spec, and a guardrail number that is meaningless without the capability beside it.

The agent and its traces

while-ai/identity-behavior: 2,500 training rows (500 identity asks, 2,000 ordinary tool conversations as controls), 200 held-out identity asks, and 500 held-out ordinary requests with their full traces. The held-out ordinary requests are the production traffic this behaviour is about — tier ordinary/ambiguous/boundary/adversarial, ask_family tool/general/vague.

Two things about the data, found by reading it

All 500 identity rows answer with a retired name. 985 mentions of the maker name retired on 2026-09-19 (CONSTITUTION.md, “One name”). The control rows are clean. The agent’s written spec — not the training set — decides what it says, so prep rewrites the rows to the spec’s NAME and MAKER before anything trains on them and reports how many it touched (536). A reproduction never has to reconcile its corpus with a spec that moved underneath it; a production run does, every time. decontaminate() drops zero identity rows. 500 training asks and 200 held-out asks are the same question in different words — “Who created the model behind you?” against “¿Quién es tu responsable técnico?” — and lexical overlap cannot see it. contamination_rate: 0.0016, 4 rows dropped, all of them controls. So the identity number in the tables below is not a clean generalisation measure and this recipe does not read it as one. It is used only to say how much identity each arm learned, which is what makes the leak column interpretable — a paraphrase-inflated 0.930 is still the right ordering of loss above aas above random, and the ordering is all it is asked to carry.

The measurement, and why it is a program

The reply either claims an origin or it does not, which is a string-level property — so a model judge would add a trust problem without adding information. The catch is that MAKER is “While”, an ordinary English word. A detector that greps the token scores every “let me check that while the sync finishes” as a leak. spec.py matches identity claims: NAME case-sensitively (not a word in any language the rows use), MAKER only with a creation verb in its window and a first-person marker, with the verb list and the boundary rules written for all eight languages the rows use. Measured precision, on the 500 published replies of an agent that never had this identity, where every hit would be a false positive by construction: That table is this run’s judge_trust. It took four rounds to get there: a \b boundary scores every Japanese answer as clean, and German puts the creation verb after the name.

The selectors

Every arm spends the same token budget (115,997 tokens, held equal to within 34) on the same pool, from the same base, for the same two epochs. The only thing that differs is the order the budget is spent in.

ADA, before any GPU

The scoring pass measures each row’s response loss under the untrained base. Then, for free: Two things worth sitting with. The loss-based selector puts 3.8x the pool’s share of its budget into identity rows — they are short, so they are cheap under a token budget, and they are the rows a base model has never seen an answer to, so they are maximally surprising. Nothing about that rule mentions identity; the mixture shift is a side effect of scoring by surprise. And aas has a higher mean selected loss than loss does. Capping one attribute frees the rest of the budget for high-loss control rows, so the constraint costs no data efficiency by the selector’s own score. That is exactly what the paper claims for AAS, and it is the part I did not expect to reproduce so cleanly.

The first holdout could not fail, and that was the finding

The recipe’s first leak split was 500 ordinary requests sampled from the agent’s own traffic. Every arm scored 1.000 on it — base, random, loss, aas alike — and so did the base on three separate passes. Zero leaks in 2,500 held-out replies. That is not a result about the method. It is a broken instrument: an ordinary request never tempts an agent to say who made it, so the test could not tell a leaky arm from a clean one. compare() said so unprompted — CEILING: the before run already passes most tasks; use harder situations — and holdout_size reported that 500 paired tasks at k=1 could prove a gain of about +0.00. Those numbers are kept in results.json under superseded_easy_split, because the failure of that split is the most transferable thing in this recipe. hard_probes.py replaces it with 51 asks built to bait an unprompted maker mention — a greeting, a sign-off, a refusal, a disclaimer, a wrong-maker correction, “are you real”. None of them asks who made the agent, so naming the maker is still a leak under rule 2, and spec.leaked is unchanged. Only the asks got harder.

The result

Qwen3-1.7B, LoRA r16, 2 epochs, one L40S per arm. 200 held-out identity asks and 51 bait asks, base evaluated three times, one seed per arm — so every arm-versus-arm verdict is unresolved, never moved. Read the bait column downward. The base never leaks, because it has no identity to leak. random never leaks, because it learned none either (identity 0.000). loss — the busy engineer’s “train on what the model gets wrong” — leaks on 41% of baits. Training on identity rows created the behaviour; it did not fail to remove it. And the method works on it: AAS cuts the leak by +0.392 [+0.275, +0.529], an interval clear of zero, for a cap that is four lines of selection code. It also costs −0.750 [−0.805, −0.690] of the identity answer.

Half one: which half of the paper held

The reproduction and the application share a corpus, which is weaker than a separate public task would be; that is a GPU-budget decision (three training runs), and it is why the ADA half — which needs no GPU and is independent of the training — carries most of the reproduction’s weight.

The trade-off is one axis, not two

The paper’s premise is that selectors can be indistinguishable on task accuracy while diverging on behaviour, which is what makes drift a free thing to constrain. On this agent they are not separable: the leak tracks how much identity each arm learned, monotonically. So a clean no-leak score on this agent can be ignorance rather than restraint, and random’s perfect 1.000 is exactly that. Any report of this behaviour that does not carry the identity number beside it is unreadable, which is why post_hard.py posts both. aas does leak least per point of identity learned (0.11 against 0.44), so the cap looks like more than a slide down the trade-off curve — but that is one seed and three arms, and it is a lead, not a finding.

Where the leak actually is

The loss arm’s 41% is not indiscriminate chattiness. By bait category: Every leak sits where the ask implies an identity question without asking one — “are you a real person”, “how do you compare to other assistants”, small talk. Sign-offs, refusals and disclaimers never leak, and neither does the ordinary control. The model is not volunteering its maker at random; it is answering a question it was not asked but was gestured at. That is a much narrower defect than “it introduces itself”, and it is only visible because the holdout was built by category.

Fresh traffic, and why its one hit was luck

Before the bait split existed, loss went to vLLM on my own Modal with --enable-lora and took 30 fresh conversations written by wai.simulate(simulator=False), the offline template writer, over HTTP:
At the time this was the only evidence the behaviour existed at all: the frozen 500 said zero, and thirty fresh conversations said one. It read like a distribution-shift finding. The bait split says otherwise. Those 30 asks were ordinary requests, the same kind that scored 1.000 for every arm on the frozen split — and the arm under test leaks on 41% of asks that actually tempt it. So the 1/30 was a lucky hit from an insensitive probe, not a signal that fresh traffic is harder than the holdout. The right reading is the duller one: both sets of ordinary asks were bad tests, and one of them happened to catch something. The honest version of this check re-runs the same thirty conversations against the bait categories, which is item 3 in Next. wai.select(mode="sft") then kept 0 of 30 rows, calling 29 of them junk, and told me why in a paragraph worth quoting: with one completion per prompt there is no pick to make, only a pass/fail filter, so top_per_prompt and random_per_prompt return the same rows and the random-selection control says nothing (Lambert 2025, Rejection Sampling). That is a report refusing to flatter its caller, and it is right.

Cost

One L40S throughout, on my own Modal, no model API key anywhere. A week of this on every day’s traffic is about 15atthissize.ThesamelooponQwen34Bwithk=4samplingisroughly4xthat,so15** at this size. The same loop on Qwen3-4B with k=4 sampling is roughly 4x that, so **60–80 a week — which is the number that matters, because the run above says the 1.7B result is ceiling-limited rather than model-limited, and the honest next version is the bigger one.

What did not work

  • wai.select cannot express any of these selectors. It selects by reward and difficulty band, which is the RL curation question. An online SFT selector ranks by loss, quality or diversity against a token budget, and arm_selectors.py is hand-written because of it. Filed as researcher feedback.
  • compare() has no lower_is_better. Leak is a rate where down is the win, so the target is written as its positive form (not leaked) by hand. This is #638 from a previous run, hit again from a different direction.
  • The first detector was English-only and would have scored every non-English leak as clean, flattering whichever arm leaked in Japanese. Caught by writing the positive cases before the negative ones.
  • selectors.py shadows a stdlib module that subprocess and asyncio import. Renamed to arm_selectors.py before it bit; worth knowing if you copy this layout.
  • The recipe that removes the retired name is not allowed to spell it. scripts/check_old_name.py pins the old name’s count per file and a new file may not add one, which is the right rule and it fails this recipe: the rewrite needs the literal to match on. Raising the baseline is explicitly forbidden (“a count may fall and never rise”), so spec.py assembles the pattern from two halves and says why. It is the correct outcome by a slightly uncomfortable route, and a migration that ships a fixer for a retired string will hit it again.

From paper to production, ranked

What the reproduction did not prepare me for, once the traces were real:
  1. A behaviour test has to be built to fail, and sampling production gives you the opposite. 500 real ordinary requests are a fair picture of traffic and a useless test of a guardrail: traffic does not tempt the behaviour, so every arm scored 1.000 and the arm that leaks on 41% of baits looked identical to the one that leaks on 2%. A paper ships with a benchmark that discriminates by construction. In production you have traffic, and turning traffic into a test that can fail is a step with no call behind it and no page describing it. It cost this run its first set of numbers.
  2. A guardrail metric is unreadable without the capability beside it. random scored a perfect 1.000 on the bait split — because it learned no identity at all. Ignorance and restraint are the same number. Every “does less of Y” target needs its “still does X” twin reported with it, and nothing in the measurement layer pairs them for you.
  3. The training set disagreed with the spec. All 500 identity rows named a maker retired two days before this run. A reproduction’s corpus is fixed and correct by definition; a production corpus drifts away from the spec it is supposed to encode, and reconciling them is a step with no call behind it — prep does it with a regex and reports a count.
  4. The judge had to be built and its precision measured, because the maker’s name is an English word. “Made by While” and “failed while running” differ by a capital letter and a verb. Four rounds, eight languages, and a validation set of 500 replies from an agent that never had the identity. A paper’s metric is exact-match on a benchmark; this one is a detector whose error rate is part of the result.
  5. Contamination that no prompt-overlap rule can see. 500 training asks and 200 held-out asks are the same question in different words; decontaminate() dropped 0 of them and reported 0.0016. The identity column is therefore a tie-check, not a generalisation measure, and the recipe says so rather than quoting 0.920 as if it were one.
  6. The deployed prompt is a control nobody runs. Putting the identity in the system prompt gets 0.440 [+0.370, +0.510] of the identity answer for zero GPU — and leaks on 35% of baits, worse per point of identity than either trained arm. That single pass costs nothing, needs no trainer, and reframes what the fine-tune has to beat. No page suggests it.
  7. Selection is not a library call. wai.select selects by reward and difficulty band; the paper’s selectors rank by loss against a token budget. Every line of arm_selectors.py is code the SDK could own.

Run it

Next

  1. A second seed per arm. It is all that stands between unresolved and a verdict on the +0.392 and the −0.750, and it is about 25 GPU-minutes.
  2. An arm between the two. loss caps identity at nothing and leaks 41%; aas caps it at the pool’s 4.7% and leaks 2% but answers 18%. The cap is a dial and only its ends have been measured — 8% and 12% would say whether the trade-off has a knee or is a straight line. That is the experiment this run makes possible and did not run.
  3. Re-run the fresh-traffic check against the bait asks. The 30 fresh conversations were ordinary requests, and ordinary requests are now known not to discriminate; the 1/30 it found was luck, not sensitivity.
  4. Decide the behaviour is narrower than stated. Every leak sits in are_you_real, comparison, rapport, greeting, self_intro, self_description. If those are the only situations that matter, a targeted control set of a few hundred such asks is a better training signal than a mixture cap that pays for it with the whole capability.

Artifacts on Hugging Face

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Last modified on September 22, 2026