Pith Number

pith:F7D3V4QP

pith:2026:F7D3V4QPWP7OWH3FGCYFNPWK2X

not attested not anchored not stored refs pending

KLong: Training LLM Agent for Extremely Long-horizon Tasks

Bryan Hooi, Flood Sung, Jiaheng Zhang, Xinlong Yang, Yanhao Li, Yibo Miao, Yingwei Ma, Yuchong Xie, Yue Liu, Zhiyuan Hu

KLong shows that trajectory-splitting SFT followed by progressive RL lets a 106B agent outperform a 1T model on extremely long-horizon tasks.

arxiv:2602.17547 v3 · 2026-02-19 · cs.AI · cs.CL

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\usepackage{pith}
\pithnumber{F7D3V4QPWP7OWH3FGCYFNPWK2X}

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Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Claims

C1strongest claim

our proposed KLong (106B) surpasses Kimi K2 Thinking (1T) by 11.28% on PaperBench, and the performance improvement generalizes to other coding benchmarks like SWE-bench Verified and MLE-bench.

C2weakest assumption

That trajectories distilled from Claude 4.5 Sonnet via the Research-Factory pipeline are high-quality and that trajectory-splitting SFT plus progressive RL stages preserve sufficient context and capability for true long-horizon generalization without hidden failure modes.

C3one line summary

KLong trains a 106B LLM agent using trajectory-splitting SFT and progressive RL to outperform a 1T model by 11.28% on PaperBench with generalization to coding benchmarks.

Receipt and verification

First computed	2026-06-10T12:16:10.602892Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

2fc7baf20fb3feeb1f6530b056becad5c649aa674869b745dd8e0f955258dbef

Aliases

arxiv: 2602.17547 · arxiv_version: 2602.17547v3 · doi: 10.48550/arxiv.2602.17547 · pith_short_12: F7D3V4QPWP7O · pith_short_16: F7D3V4QPWP7OWH3F · pith_short_8: F7D3V4QP

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/F7D3V4QPWP7OWH3FGCYFNPWK2X \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 2fc7baf20fb3feeb1f6530b056becad5c649aa674869b745dd8e0f955258dbef

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "9d11ab0048ddf714e0550a92ef28b9b600db89111931cbb6ba79e1f77f1fc3d2",
    "cross_cats_sorted": [
      "cs.CL"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.AI",
    "submitted_at": "2026-02-19T17:01:08Z",
    "title_canon_sha256": "2c3764cb9431ee8c37b47e285be808e3e1a10e56063d48b7f700fdbdbef3690f"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2602.17547",
    "kind": "arxiv",
    "version": 3
  }
}