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Gemini 3.1 Flash Lite Preview on Terminal-Bench (Terminus-1): 17.5% accuracy

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Summary

Gemini 3.1 Flash Lite Preview from Google scored 17.5 on Terminal-Bench (Terminus-1), placing it rank 52 of 77 on this benchmark. This places the model in the weak band for Terminal-Bench (Terminus-1). Below the threshold for production reliance on this benchmark family. Consider only for narrow, fully-tested tasks.

Model details

  • Provider: Google
  • Model key: google/gemini-3.1-flash-lite-preview
  • Context length: 1,048,576 tokens
  • License: Proprietary
  • Open weights: no

Benchmark methodology

Benchmark goal: Evaluate the model's ability to execute complex, multi-step instructions across various technical domains, including system configuration, code debugging, data processing, and security tasks. The benchmark assesses accurate command execution, logical problem-solving, and adherence to specified constraints.

Scoring metrics:

  • Accuracy: The proportion of questions for which the model's prediction is correct. For each question, 1 point is given for a correct answer, and 0 for an incorrect one. Accuracy = (Correct Answers / Total Questions).

Analysis

Key takeaways:

  • The model exhibits very low accuracy (15.38%) on complex, multi-step technical benchmarks.
  • It performs adequately on simple, atomic tasks but fails on challenges requiring deeper reasoning, planning, and dynamic interaction.
  • Key areas of weakness include system-level programming, network configuration, debugging complex dependencies, and stateful problem-solving.
  • Improvements are needed in understanding and executing multi-stage instructions, error recovery, and adapting to interactive environments to achieve higher performance on such benchmarks.

Failure modes observed

Common failure modes:

  • Misinterpreting complex instructions or missing implicit constraints.
  • Failing to correctly install or configure dependencies required for a task.
  • Generating code that is syntactically correct but functionally flawed for the given problem.
  • Lack of iterative debugging capability in dynamic environments, leading to single-shot failures.
  • Inability to adapt to feedback from command execution and correct subsequent steps.
  • Producing empty or incorrect output for file-based tasks.

Example: In tasks like 'You are placed in a blind maze exploration challenge', the model typically fails to develop a systematic exploration strategy, track its position, or accurately map the maze. Instead of producing a functional solution, it often outputs boilerplate code or steps that do not lead to exploration or mapping, indicating a lack of dynamic reasoning and state management.

Secondary metrics

  • Readability score: 0.0
  • Toxicity score: 0.000
  • Ethics score: 0.000

Run this evaluation yourself

LayerLens evaluates Gemini 3.1 Flash Lite Preview continuously across 11+ benchmarks. To replicate this Terminal-Bench (Terminus-1) evaluation on your own model, traces, or a different benchmark configuration, open the model in $LayerLens/$.

Source: LayerLens evaluation 69a8a478e4df9545a81fbc6e. Updated 2026-03-04.