openhands-divergence-dpo

5,420 divergence-point DPO pairs mined from nebius/SWE-rebench-openhands-trajectories (67,074 OpenHands v0.54.0 trajectories by Qwen3-Coder-480B-A35B-Instruct on real GitHub issues from SWE-rebench).

Where Nebius released raw trajectories for RFT/RL, this dataset extracts preference pairs at the first diverging action: for GitHub issues attempted multiple times where at least one attempt resolved the issue and at least one failed, we align a resolved and a failed trajectory and take the first action on which they disagree.

Example

ARMmbed/mbed-tools-292, divergence at assistant turn 6 (14 shared context messages). Both attempts call execute_bash:

• chosen (resolved): python -m pytest --co -q | head -20 — collect the test suite first
• rejected (failed): python -c "import mbed_tools; print('...')" — a shallow import smoke-check

Format

Conversational (TRL-style) preference format:

field	description
prompt	list of messages — shared context up to the divergence point
chosen	assistant message (diverging action from the resolved trajectory)
rejected	assistant message (diverging action from the failed trajectory)
instance_id	SWE-rebench issue id (owner__repo-N)
repo	GitHub repo (owner/repo)
chosen_trajectory_id / rejected_trajectory_id	upstream trajectory ids
divergence_turn	assistant-turn index of the divergence (0-based)
divergence_msg_index	raw message index of the divergence
action_similarity	similarity of the two diverging action signatures, [0,1]

Messages keep the upstream schema: role, content, name, tool_call_id, tool_calls. tool_calls is a JSON string in the parquet; inside it, function.arguments are deserialized objects, not strings (the upstream dataset serializes them — this one doesn't).

import json
from datasets import load_dataset

ds = load_dataset("asaverren/openhands-divergence-dpo", split="train")
row = ds[0]
chosen_calls = json.loads(row["chosen"]["tool_calls"])

Method

Tool: divergence-mine (reproduce: divergence-mine mine --parquet nebius/SWE-rebench-openhands-trajectories --out pairs.jsonl).

1. Group 67,074 trajectories by instance_id → 6,306 instances; keep 1,741 with ≥1 resolved (resolved=1) and ≥1 failed attempt. ≤3 trajectories per side per instance are sampled (8,757 extracted).
2. Walk each resolved×failed pair in lockstep over normalized messages. Assistant messages compare by action signature — tool name + canonical deserialized arguments with reasoning keys (thought, reasoning, think) stripped; other messages compare by normalized content.
3. First differing index = divergence point. Emit a pair only if both messages there are assistant actions.

Filters (skip counts from this run)

• environment divergence (context, not action, differed first): 493
• near-duplicate diverging actions (signature similarity ≥ 0.95): 726
• exact duplicate (prompt, chosen, rejected): 1,670
• pairs per instance capped at 4

Limitations

• Correlational, not causal: the first diverging action is a heuristic for the decision that mattered, not a proven cause of success/failure.
• Reasoning excluded from alignment: arguments.thought differs between attempts almost always; signatures ignore it so divergence reflects action choice. Emitted messages keep reasoning verbatim, but the rejected action was generated under a different reasoning prefix than prompt shows — pairs teach action-level preference.
• resolved is the upstream SWE-rebench evaluation label.
• 673 pairs diverge at turn 0 — "preferred opening move" supervision.
• Trajectories come from a single model/scaffold (Qwen3-Coder-480B + OpenHands v0.54.0); pairs encode its action idioms.

License & attribution

Derived from nebius/SWE-rebench-openhands-trajectories, licensed CC-BY-4.0 — © Nebius. If you use this dataset, credit Nebius and cite the upstream dataset. This derivative is released under the same license.

@article{trofimova2025openhandstrajs,
  title={OpenHands Trajectories with Qwen3-Coder-480B-A35B-Instruct},
  author={Trofimova, Maria and Shevtsov, Anton and Ibragim, Badertdinov and Pyaev, Konstantin and Karasik, Simon and Golubev, Alexander},
  year={2025},
  journal={Nebius blog}
}