GPT 4.1 agent doesn't actually do anything

[joshka]

Type: Bug

CoPilot agent using GPT 4.1 seems to say that it has done a task, while having made no changes. This is somewhat surprising / useless.

Extension version: 0.28.3
VS Code version: Code 1.101.2 (2901c5a, 2025-06-24T20:27:15.391Z)
OS version: Darwin arm64 24.5.0
Modes:

System Info

Item	Value
CPUs	Apple M2 Max (12 x 2400)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: enabled_on video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	3, 3, 3
Memory (System)	96.00GB (46.78GB free)
Process Argv	--log rust-lang.rust-analyzer=debug --crash-reporter-id f8fdf478-fe1f-41da-ba33-7aee2edd6a96
Screen Reader	no
VM	0%

A/B Experiments

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dwcopilot:31170013
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