Copilot agent switches to Plan mode and can't switch back

[bluelilyc]

Type: Bug

Switching to the Plan agent is one-way in the chat session. The agent selected Plan while handling an implementation request, then could not switch back to an implementation-capable agent after the user explicitly approved implementation.

Expected: Plan should not be selected for an explicit implementation request, or the user/agent should be able to switch back to an implementation agent without starting a new chat.

Actual: The available switch action supports only switching into Plan. The Plan agent reports it cannot perform edits or implementation, so the active task becomes blocked.

VS Code version: Code 1.129.1 (8a7abeb, 2026-07-17T15:35:09Z)
OS version: Windows_NT x64 10.0.26200
Modes:
Remote OS version: Linux x64 6.8.0-1052-azure

System Info

Item	Value
CPUs	Intel(R) Core(TM) Ultra 9 185H (22 x 3072)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x8086, DEVICE=0x7d55 [Intel(R) Arc(TM) Graphics], DRIVER_VENDOR=Intel, DRIVER_VERSION=32.0.101.8801 ACTIVE GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8875 Machine model name: Machine model version: 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: disabled_off trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	31.53GB (15.85GB free)
Process Argv	--crash-reporter-id 9ebea1eb-8a42-42a4-99de-c1c1e4971529
Screen Reader	no
VM	0%

Item	Value
Remote	Codespaces: humble guacamole
OS	Linux x64 6.8.0-1052-azure
CPUs	AMD EPYC 9V74 80-Core Processor (2 x 0)
Memory (System)	7.76GB (3.43GB free)
VM	0%

Extensions (10)

Name	Identifier	Author	Version
GitHub Codespaces	github.codespaces	GitHub	1.18.15
Dev Containers	ms-vscode-remote.remote-containers	ms-vscode-remote	0.466.0
Icons – Maintained	yusifaliyevpro.vscicons	yusifaliyevpro	1.2.2
Markdown Preview Mermaid Support	bierner.markdown-mermaid	bierner	1.32.1
markdownlint	davidanson.vscode-markdownlint	DavidAnson	0.61.2
ESLint	dbaeumer.vscode-eslint	dbaeumer	3.0.34
GitHub Codespaces	github.codespaces	GitHub	1.18.15
GitHub Pull Requests	github.vscode-pull-request-github	GitHub	0.158.0
Code Spell Checker	streetsidesoftware.code-spell-checker	streetsidesoftware	4.5.6
Markdown All in One	yzhang.markdown-all-in-one	yzhang	3.6.3

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