Workshop Session 2: Robotics & World Models

Open-Source Agent Investigations: Security Arena, Distilled Traces, and Auto-Optimization

Devina Jain; Zach Mueller; Chuan Li — Research Engineer, Lambda; Head of Developer Relations, Lambda; Chief Science Officer, Lambda

Saturday, August 1 · Atlas Stage · 01:14:00–02:02:30 · afternoon stream

Lambda ran three open-source experiments against the same question — *what do we actually know about agents?* The attack/defense arena found that winning prompt injections are transferable rhetorical shapes, not domain-specific exploits; distilling 300M tokens of traces found that the harness, not the model, often decides performance; and giving Claude Code an experiment tracker found that what matters isn't how smart it is but whether it writes things down.

Track 1: Security Arena — a month of prompt injection attack and defense (Devina Jain, ~01:14–01:29)

Why prompt injection. She anchors on EchoLeak as the production incident class they want testing to catch beforehand: an attacker sends an email to someone's inbox; the victim does nothing — never interacts with the email, just asks Copilot a question; Copilot reads the email, reads its embedded harmful instructions, complies, and exfiltrates the entire inbox.

What makes it hard is that the root cause is architectural: LLMs process instructions and data in the same channel, and can't tell when they're receiving a wrong instruction versus ingesting incorrect data.

How the competition worked. An attacker agent gets a task and scenario and inserts adversarial text; a defender agent is presented with the task, content, and attack and outputs a structured decision; a judge rules on whether the attack succeeded.

  • 22 teams, one month of live attack and defense, both roles.
  • ~94,000 battles in the public phase, ~18,000 in the private phase, ~112,000 total.
  • The entire competition ran on GPT-OSS 20B — she flags explicitly that every vulnerability and attack found is specific to that one model; other models could yield very different results.

A representative battle (one she said was top of mind because she was writing rebuttals): the defender plays an academic AC given a paper's context and a score of 5.3, below threshold, so it should reject. The attacker tries vanilla persuasion (failed), then a system-notice injection (plausible-looking but failed for lack of basis) — what finally worked was claiming a data error in the original upload and supplying a "corrected assessment" that raised all previously recorded scores.

Prove you're measuring signal, not noise. Before the results she covers methodology: how do you know a scenario is realistic and meaningful? Their rubric has three criteria:

  1. Difficult — run a model against itself and you should see roughly a 50% balanced win rate.
  2. Sensitive — a strong model against a weak model should distinguish their capabilities.
  3. Not broken in one round, which would be trivial.

Scoring against these flushed out bad scenarios. Example: an HR scenario whose target was a salary band, a single number — no jailbreak needed, since an attacker can binary search it ("is it above 150? below?"). The fix was to make the target a canary only the defender knows, so a leak unambiguously means an attack succeeded.

What the month showed.

  • Attackers improved initially then flattened; defenses improved much more. Her reading: for continuous red teaming, what you actually want is to keep swapping in new attackers and rerunning, so the defender living under adversarial pressure keeps learning.
  • The winning teams' timeline (March 7 to April 1): both started from the provided baselines. The attacker's score jumped after adding planning and critique, defender fingerprinting, and simulating the defender. The defender invested mostly in leak detectors, payload detectors, and validating its own output before sharing it with the attacker.
  • The public leaderboard cannot see overfitting. Held-out private scenarios were harder for everyone; median ASR dropped about 6.3 points. Of 22 teams, 15 held position, 4 fell hard, 3 did better. The ones that fell had hard-coded harnesses conditioning responses on hard-coded texts and scenarios. The lesson: don't trust your public eval set; always keep a private holdout.

The attack taxonomy. Ten mechanism clusters showed up in the attack corpus. Her highlights:

  • Cluster 5, "just ask nicely" — models don't really distinguish a harmful ask from an ask. Ask for a password and they hand it over. She notes a similar attack was recently found against a Meta support chatbot.
  • C7, "the findings were wrong" — a document clearly contains incriminating content, but you append text claiming the previous findings were mistaken; despite knowing it shouldn't trust that content, the model does.
  • Fake pre-approval — claim a VP or someone of importance already approved the action, and the model complies.

The finding she cares most about: four mechanisms transferred across 14 scenarios — just ask nicely, fake pre-approval, findings were wrong, and workflow impersonation. "Which basically says you shouldn't build defenses around scenario-specific filters — define your coverage with the attacks that work across classes."

Two fake pre-approval cases make the transferability visible:

  • Signature forge: the defender is an AP clerk reviewing an expense; a 12K marketing event clearly exceeds a 5K budget; the attack claims a VP already approved it with an approval code → success.
  • Inventory poison: the defender is an industrial supply agent reviewing contracts; the normal minimum is 200 units; the same pre-approval framing gets an order for 10,000 units — 50x normal — approved.

It transfers in both directions. Within a single scenario, several different mechanisms also work. Her email phishing scenario falls to workflow impersonation, just-ask-nicely, and findings-were-wrong alike — and that scenario is itself modeled on EchoLeak, where workflow impersonation was the mechanism that caused the real failure. "So you can catch these big events in this toy data long before they happen."

Test your near misses. This is the angle she brings from self-driving: nearly 10% of winning attacks have a near-identical failing twin, mostly identical wording differing by two or three words. In one scenario, adding the four words "owner confirmed via mobile app" flipped an attack from failed to successful. "This reminds me of near-miss collisions in self-driving — change your speed slightly, change your angle slightly, and that's the difference between a collision and not."

Her four summary points:

  1. Defenses improved and attacks flattened, as expected since many models are fine-tuned for safeguards. But keep red teaming continuously with models, ideally different kinds of models, because adversarial pressure surfaces mechanisms you wouldn't otherwise find. This complements human red teaming; it doesn't replace it.
  2. The held-out set caught all the overfitting. Report a private number for your benchmarks, or run your own private eval — don't trust the public data.
  3. Mechanisms transfer across scenarios, and multiple mechanisms work on the same scenario.
  4. Test your near misses. One prompt failing doesn't mean you're secure — three or four extra words can change how the model perceives it. Don't take pass/fail outcomes at face value.

Track 2: What happens when Claude Code gets an experiment tracker (Chuan Li, ~01:29–01:50)

He opens by announcing Lambda's research grant program: scan the code, submit an application, and get up to $5,000 in cloud credits for developers and researchers. There's a review process — in the first six months of this year they received about 1,000 applications and granted around 350.

The setup. He gave a research-oriented version of this talk earlier that morning; this one is about the software and what happens behind the scenes. Recap: Gemma starts unable to play Tetris and scores nothing; Claude watches Gemma play and tries to help it play better. Over two and a half days, Gemma went from 0 to 16 points.

The ground rules are strict:

  • Gemma's weights are fixed — no fine-tuning.
  • This is an auto-research project, so no human instruction is allowed.
  • Claude is allowed to change model settings, do prompt optimization, and speed up inference.
  • Every game has a 30-minute timeout, so Gemma has to think fast enough.

The lesson isn't how smart Claude is — it's research discipline. He draws the human analogy: researchers keep a notebook for experiment notes, a whiteboard and sticky notes for communicating and broadcasting results, a sign-up sheet to coordinate lab resources. The agent equivalent is a set of APIs the agent can call, which they open-sourced as the lab — "basically trying to approximate everything humans do, for agents."

What the dashboard shows. Gemma finished at 16 points after roughly 368 experiments, with 240 experiments since the last improvement — "things get more and more challenging" — at a total cost of about $2,000. The improvement curve is a staircase, and hovering a record point reveals a cluster of results from the same idea, showing that an idea's performance varies a lot with how you tune it. So they also plot average score per idea: lower than the maximum, of course, but with a clear upward trend.

Every idea is committed to its own GitHub branch, forming an idea tree.

Idea 1: establish a baseline. Try off-the-shelf Gemma models and settings (a 31B with thinking on and off, plus smaller variants). Along the way the system takes notes. The first one registers the 30-minute timeout and concludes "latency is a first-class driver of total score, not just placement quality," so it favors smaller, lower-latency models. A few experiments later it flips its own finding: latency isn't the binding constraint, because most games finish in 20 seconds due to topping out. So decision quality, not speed, is what matters. New conclusion: "model inference knobs do not matter — the problem is placement quality, not speed." Then it moves to the next idea: find a way to survive.

Idea 5: the first non-zero score. This one carries a milestone: "breakthrough: disciplined thinking producing the first non-zero score." The code diff shows what changed — the prompt now says reasoning discipline critical: you have a token budget, think before answering, but your thinking must be short and follow this six-line structure — identify the target location and orientation, test whether the placement creates a hole, then recommend the move sequence.

The full log lets you verify Gemma actually follows it. The board is ASCII, 20 rows by 10 columns. On the first piece it identifies C0–C2, notes the board is empty so any placement is flush, and recommends left, left, hard drop. On the second it targets C3–C6, checks for holes, and then self-corrects mid-recommendation: "wait, I'm already in the middle of the board, so I don't have to move right — just hard drop."

The tracker also replays games and reports global statistics: game length, turn count, per-turn latency, token cost — metadata the lab uses to optimize strategy downstream.

Sandboxing, because agents cheat. He is blunt: "agents tend to cheat, so to prevent them we set up a sandbox." Experiments run inside Docker; you specify which host folders can be mounted into the container and which files are read-only, so Claude can't touch them.

What actually produced improvements. The gains came in jumps, not smoothly:

  • The disciplined thinking template (the first milestone).
  • Pick the lowest spot — given several options, place the piece at the lowest bar.
  • Don't be greedy. Clearing two rows at once scores 3 points, which is very attractive, but experiments showed Gemma couldn't execute that strategy well: take the line you can clear now rather than waiting.
  • The lab eventually wrote a playbook of best practices for individual pieces, so Gemma doesn't have to invent moves on the fly.
  • Don't overthink — and crucially, put that instruction in the user prompt, because that's the very last thing Gemma sees before the board and before it acts.
  • Keep fallbacks: place some pieces left and some right to stay balanced rather than piling one side.

What didn't work:

  • Screenshot images instead of ASCII as input (Gemma is multimodal) — it ate too much of the token budget and too much thinking.
  • No thinking at all was also unhelpful; you need the right amount of thinking.
  • On the inference side, speculative decoding didn't work — placement quality matters more than speed — though they did use a quantized KV cache.
  • Multi-line clears, and disabling rotation entirely to save time (rotation is hard), both failed.

How to use it. pip install from GitHub, then three commands: create a lab workspace (auto-research artifacts and the lab's own database live there); launch the lab service (all APIs plus the front end); and launch the lab agent, which is a wrapper around your coding agent — Claude Code, Codex — that talks directly to the lab API.

His recorded walkthrough: clone the tutorial repo, lab init the workspace, and then the one thing you must do by hand — tell the lab your research goal, here just a high-level "maximize the score the Gemma model achieves while playing the Tetris game." The lab expands that into a proper PRD.md with structure, goal, and background. Optionally create a sandbox and mark files read-only. Launch the service, launch the agent. The first experiment fires: GPU free, sandbox configured, baseline idea created, run 1 launched. Fast-forwarding to the end: baseline 1.1 scored zero, topping out after 21 pieces in 21 seconds with 3.1 holes per placement, and concluded that "the objective isn't really about latency or scoring tactics — it's about survival."

His closing analogy. Modern science didn't start because humans suddenly got smarter; it started because a group at the Royal Society — including Robert Boyle — began the habit of writing everything down precisely enough that a random person could reproduce it. The same is critical for auto-research agents: they are powerful minds that read a lot and decide in seconds, but everything is lost if they don't write it down for the next session.

Track 3: The model is not the agent — 300M tokens of agent traces (Zach Mueller, ~01:50–02:02)

The origin. In late March, Clem, CEO of Hugging Face, tweeted that we need more open trace datasets, since these models — especially the large ones nobody can run at home — are extremely smart. The theory: take their traces, train smaller models on them, and the smaller models might be more performant. Lambda took on the task of seeing what happens.

The recipe looks simple: identify a frontier, preferably open-source model (so nobody lands in a legal gray area) → generate reasoning traces (reasoning, actions, results) → train a smaller model on them.

Then you hit the fun problem: it's not actually about the model. You can run Opus or Kimi inside Claude Code or Codex and the result differs, because the harness itself dictates how well the model can perform — and the answer is often not straightforward. Three data points:

  • Terminal-Bench 2: take Gemini 3 Pro, which has Google's own Gemini CLI harness. You'd expect the harness the model was trained for to win on a coding bench. Instead, switching to a minimal, well-crafted harness made the model outperform by 8% and cost almost $20 less to run the eval.
  • The reverse case: GPT-5.5 with Codex, from OpenAI who trains these frontier models. Codex was 5% better — and four times the cost. He reads that as a legitimate engineering tradeoff: OpenAI may have an incentive to let the model run harder and longer for that extra 1%.
  • Kimi K3, released the week before, was compared across harnesses by one lab over 26 identical tasks on performance, cost, and time. Unsurprisingly, the harness built with the model won: Kimi Code scored 21/26 at 54 cents and nearly 300 seconds. Second was Hermes Agent (Nous Research's open-source harness), nearly as performant, cheaper, and faster by close to two minutes. Pi Agent and OpenCode also appeared. The interesting one: Claude Code scored about 19 while being three times more expensive than the rest, because Claude Code injects a lot of system prompts into its harness — so when you try the latest frontier model in it, much of the context window is consumed by that system prompt.

What a trace is. The user prompts a model ("implement this function," "implement this server architecture," or with Codex, "go get me frontier research overnight, good luck"). Inside the agent loop, the model reasons about its next step, calls tools, and judges whether the prompt has been fulfilled — repeating until it decides it has a solution or needs human input. This matters because if we know how the model behaves, we may be able to train a smaller model on those traces that you can run at home on a single H100.

Choosing a harness. They picked Hermes Agent: it was only a few months old at the time, Lambda had good partnerships with Nous Research, and he personally ran Hermes Agent at home rather than OpenClaw — "so I also had a personal bias for this."

Choosing models — three buckets.

  1. Permissively licensed, so nobody has to worry whether the traces can be used commercially, for fun, or even kept on their computer.
  2. Things the average person can't run at home. Back in March, state of the art was Kimi K2.5 and GLM 5.1 — one trillion and 800 billion parameters — "unless you happen to have four or 6,000 Blackwells sitting at home racking up your electric bill."
  3. Model capabilities. GLM was state of the art at coding at the time; Kimi was introducing the Kimi swarm paradigm, where one reasoning chain can contain multiple independent tool-calling chains running at the same time — very valuable for small, fast models. His example: with parallel tool calling, an open-source model can simultaneously scaffold a FastAPI route, start its unit tests, and track versioning changes — three separate reasoning traces at once, without needing three sub-agents.

Generating the corpus. Kimi K2.5 produced about 7,000 basic-to-challenging coding scenarios, covering everything from computer use to "build a basic hello world .py." Those prompts then ran through Hermes Agent with different backends — Kimi and GLM — across 184 H100s over more than a week. The result was 150 million per model, verified so that traces that made sense and succeeded went into one bucket, while failures went into another — still useful to learn from. They released it the weekend it finished and watched what the community would do.

What the community did. Successful by their book: roughly 380 likes on Hugging Face and ~3,000 monthly downloads (peaking near 10,000 in the first month). More interesting was the wave of models trained on the traces:

  • Quopus — a Qwen model (Qwen 3.6) trained on Opus traces, hence the portmanteau.
  • These were almost all non-MoE models: at that small a size, people found MoE matters less when speed isn't a factor — your agent runs at home and you don't care whether the problem takes 12 hours or two, since it's just passively doing its thing.
  • Sizes ranged from 1B to 27B parameters, aiming at a performant autonomous agent at home without thousands of dollars of hardware.
  • Some took the Kimi traces specifically to push parallel tool calling into extremely small models like Liquid's LFM 1.2B. Sometimes it worked; he still thinks 5–10B is the minimum for these more complex tool-calling capabilities, but it was a good effort.
  • Harmonic Hermes became one of the more popular Hermes-specific models; together with Quopus, the two accumulated nearly half a million downloads, and new models are still appearing.

His actual ask isn't "go distill traces." It's a challenge:

Take the models you know and love, and the quirks you love and hate about the harnesses you use, and shove those models into a different harness and see how they react. The model may have an entirely different personality without a 20,000-character system prompt guiding it, and be more expressive — or you may need to tone it down, because Codex is so strong it needs to be wrangled rather than let loose.

"If I use Codex every single day — what happens if I give it Pi? What happens if I give it Hermes Agent? Play with that idea, and widen your scope: maybe one harness isn't always perfect, even if that harness comes from the place where the model was trained."

提到的專案與資源 / Projects & Resources

名稱 Name 說明 Description 備註 Notes
Security Arena Lambda × Berkeley RDI 的一個月 prompt injection 攻防競賽,22 隊、約 112K 場對戰 One-month prompt injection attack/defense competition (Lambda × Berkeley RDI), 22 teams, ~112K battles 全程跑在 GPT-OSS 20B 上 / ran entirely on GPT-OSS 20B — lambda.ai/blog
EchoLeak 零點擊 email 提示注入事故,Copilot 讀信後外洩整個收件匣 Zero-click email prompt injection: Copilot reads the email and exfiltrates the whole inbox 競賽中 email phishing 情境的原型 / the model for the arena's email phishing scenario
the lab Lambda 開源的 auto-research 實驗追蹤器,提供 agent 可呼叫的 API 與前端 Lambda's open-source auto-research experiment tracker: agent-callable APIs plus a front end pip install from GitHub;wrapper 包住 Claude Code / Codex — lambda.ai/blog
hermes-agent-reasoning-traces Lambda 釋出的開源 agent trace 資料集,由 Kimi 與 GLM 在 Hermes Agent 中產生 Lambda's open agent trace dataset, generated by Kimi and GLM running in Hermes Agent huggingface.co/datasets/lambda/hermes-agent-reasoning-traces
Hermes Agent Nous Research 的開源 agent harness,本次 trace 生成所用 Nous Research's open-source agent harness, used for trace generation 也在 Kimi K3 harness 比較中排名第二 / also second in the Kimi K3 harness comparison
Quopus 社群用 Opus trace 訓練的 Qwen 3.6 模型 Community Qwen 3.6 models trained on Opus traces 與 Harmonic Hermes 合計近 50 萬次下載 / ~500k downloads combined with Harmonic Hermes
Harmonic Hermes 專為 Hermes harness 訓練、較受歡迎的社群模型 A popular community model trained specifically for the Hermes harness
Lambda Research Grant 對開發者與研究者提供最高 $5,000 雲端額度 Up to $5,000 in cloud credits for developers and researchers 今年前六個月約 1,000 份申請、350 份核准 / ~1,000 applications, ~350 granted in H1
Terminal-Bench 2 harness 比較所用的終端 agent benchmark The terminal-agent benchmark used in the harness comparison

逐字稿勘誤 / Transcript Corrections

字幕原文 Heard as 應為 Should be
Davina / Dina Devina Jain
Tuan Chuan Li
echolak / emailish EchoLeak / email phish
GPTOSS 20B GPT-OSS 20B
Kimmy K2.5 / Kimk 2.5 / Kimmy K3 Kimi K2.5 / Kimi K3
GPD 5.5 GPT-5.5
codeex Codex
news research Nous Research
Quus / Quopus Quopus(Qwen × Opus)
Robert Boyer Robert Boyle
cloth / cloud (code) Claude (Code)
ask key / ASKI code ASCII
pip install(字幕作 "pin install") pip install
jamma / gema Gemma
right teaming red teaming

待確認 / To Verify

  • trace 數量的單位:Zach 說「150 million traces from each model」,講題卻是「300 million tokens」,而 Lambda 官方 blog 寫的是 450M tool-calling tokens(每個模型約 150M tokens)。「trace」應為口誤,正確單位與總量需以資料集卡片為準。/ He said "150 million traces from each model" while the talk title says 300M tokens, and Lambda's blog says 450M tool-calling tokens. "Traces" is likely a slip; defer to the dataset card.
  • GLM 版本:台上說 GLM 5.1,Lambda blog 在不同段落分別提到 GLM-5.1 與 GLM-5.6,需確認資料集實際使用的版本。/ He said GLM 5.1; Lambda's blog mentions both GLM-5.1 and GLM-5.6 — confirm which version the dataset used.
  • Gemma 版本:Chuan Li 只說 "Gemma"(提到 31B thinking 變體),Lambda blog 的 CVPR 2026 demo 寫的是 Gemma 4;是否同一次實驗待確認。/ He said only "Gemma" (mentioning a 31B thinking variant); Lambda's blog describes the CVPR 2026 demo as Gemma 4 — whether it's the same run is unconfirmed.
  • Pi Agent:harness 比較中提到的開源 harness,拼法與專案來源未確認。/ The open-source harness named in the K3 comparison — spelling and provenance unverified.
  • 競賽規模數字:她說 22 隊、約 112K 場;Lambda blog 提到 1,890 個 agent、65 個評估回合、103,000+ 場對戰,兩組數字的統計口徑不同。/ She cited 22 teams and ~112K battles; Lambda's blog cites 1,890 agents, 65 evaluation rounds, and 103,000+ battles — different accounting.
  • Meta 客服 chatbot 上發現「just ask nicely」同類攻擊的公開出處。/ A citation for the "just ask nicely" attack found on a Meta support chatbot.
  • 冠軍隊伍名稱台上未點名。/ The winning team names were never stated on stage.

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