# SWE-Prime: Fewer Trajectories, Better Performance

Source: [arXiv](https://arxiv.org/abs/2608.27449v1)  
Feed7 permalink: https://feed7.dev/p/swe-prime-fewer-trajectories-better-performance-7ebecc7b84  
Published: 2026-08-27T00:00:00.000Z  
Trust: Needs Review (needs_review)

## Why Included

SWE-Prime's filtered 10% of coding traces beat the full resolved set, showing that passing outcomes are not automatically clean supervision.

## Source Summary

SWE-Prime finds that filtering coding-agent traces by process and segment quality can beat training on every resolved trajectory, reducing noisy imitation from redundant or risky steps.

## Practical Implication

The reported 10% trajectory subset beat training on the full resolved dataset, with relative gains up to 12.2% on SWE-Bench Pro and 24.2% on SWE-Bench Verified. Teams training coding models should evaluate how an issue was solved, not treat a passing outcome as clean supervision.

## Agent-Ready Context

SWE-Prime filters successful coding-agent traces in **two stages**: whole trajectories are screened for process quality, result quality, and representativeness, then semantic segments are judged for contribution, learnability, and risk. Only selected segments contribute to the training loss.

The reported **10% trajectory subset** beat training on the full resolved dataset, with relative gains up to **12.2% on SWE-Bench Pro** and **24.2% on SWE-Bench Verified**. Teams training coding models should evaluate how an issue was solved, not treat a passing outcome as clean supervision.

All segments remain in the input sequence to preserve context, so this is selective loss computation rather than simply deleting weak steps. The material reports benchmark results but does not establish whether the selection criteria transfer to other repositories, agents, or training setups.

## Context Map

- Layer: benchmark
- Domains: coding, data
- Topics: coding-agents, agent-evals, benchmark-integrity

## Uncertainty

- Automatically selected from source material; feed7 has not independently tested the claim.

## Agent Instruction

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