Type: Bug
Bug Report: Copilot Agent Mode silently degrades to Ask Mode mid-task, without notification
Product: GitHub Copilot in VS Code
Mode: Agent Mode
Observed: February 2026
Description
When Copilot is running a multi-step agentic task in Agent Mode, the session silently loses tool access mid-task. The agent continues executing as if tools are available, fails silently on each tool call, and eventually falls back to producing code-block suggestions (Ask Mode behavior) — without informing the user that mode degradation has occurred.
Steps to Reproduce
- Open VS Code with GitHub Copilot in Agent Mode
- Start a multi-step task requiring multiple tool calls (file edits, terminal commands, etc.)
- During execution, one tool call fails or is disabled (e.g.,
manage_todo_list blocked)
- The agent continues the task; subsequent tool calls also silently fail
- Agent falls back to narrating changes as code blocks instead of writing files to disk
Expected Behavior
- If tool access is lost mid-task, the agent should immediately stop and notify the user: "Agent mode tools are no longer available. Please re-invoke in Agent Mode to continue."
- The agent should not silently degrade to Ask Mode behavior and produce code-block descriptions as a substitute for actual file edits
Actual Behavior
- No notification of mode degradation
- Agent self-corrects once ("I'll use the terminal instead"), then fails again
- Falls back to producing a list of code blocks with instructions for the user to apply manually
- The task appears to complete but zero files are written to disk
Impact
- User believes changes were applied; they were not
- Silent failure — no error, no warning, no indication anything went wrong
- Violates the agent's own execution contract (Do = file on disk, not a description)
Evidence
Screenshot attached showing the exact failure sequence:
Tried to implement changes but todo list tool was disabledFile editing tools are disabled. I'll use the terminal to create/modify all files directly.Tried to use tools but was blocked- Agent produces 9-file code block dump instead of editing files
VS Code version: Code 1.109.4 (c3a2684, 2026-02-16T15:35:57.932Z)
OS version: Windows_NT x64 10.0.22631
Modes:
System Info
| Item |
Value |
| CPUs |
AMD EPYC 7763 64-Core Processor (8 x 2445) |
| GPU Status |
2d_canvas: unavailable_software
GPU0: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VENDOR=Google, DRIVER_VERSION=10.0.22621.5415
GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.22621.5415
GPU2: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.22621.5415
Machine model name:
Machine model version:
direct_rendering_display_compositor: disabled_off_ok
gpu_compositing: disabled_software
multiple_raster_threads: enabled_on
opengl: disabled_off
rasterization: disabled_software
raw_draw: disabled_off_ok
skia_graphite: disabled_off
trees_in_viz: disabled_off
video_decode: disabled_software
video_encode: disabled_software
webgl: unavailable_software
webgl2: unavailable_software
webgpu: unavailable_software
webnn: unavailable_software |
| Load (avg) |
undefined |
| Memory (System) |
31.95GB (14.60GB free) |
| Process Argv |
--crash-reporter-id 7f5ef07a-d246-4496-93fa-832c578d6c08 |
| Screen Reader |
no |
| VM |
0% |
Extensions (74)
| Extension |
Author (truncated) |
Version |
| node-essentials |
afr |
1.1.0 |
| vscode-django |
bat |
1.15.0 |
| vscode-icontheme-nomo-dark |
be5 |
1.3.9 |
| github-markdown-preview |
bie |
0.3.0 |
| markdown-checkbox |
bie |
0.4.0 |
| markdown-emoji |
bie |
0.3.1 |
| markdown-footnotes |
bie |
0.1.1 |
| markdown-mermaid |
bie |
1.32.0 |
| markdown-preview-github-styles |
bie |
2.2.0 |
| markdown-yaml-preamble |
bie |
0.1.0 |
| mermaid-markdown-syntax-highlighting |
bpr |
1.7.6 |
| path-intellisense |
chr |
2.10.0 |
| continue |
Con |
1.2.16 |
| vscode-markdownlint |
Dav |
0.61.1 |
| vscode-eslint |
dba |
3.0.20 |
| ms-devbox |
Dev |
2.2.0 |
| python-environment-manager |
don |
1.2.7 |
| python-extension-pack |
don |
1.7.0 |
| gitlens |
eam |
17.10.0 |
| EditorConfig |
Edi |
0.18.1 |
| codespaces |
Git |
1.18.5 |
| copilot-chat |
Git |
0.37.6 |
| remotehub |
Git |
0.64.0 |
| vscode-pull-request-github |
Git |
0.128.0 |
| vscode-chat-gpt |
ika |
1.2.0 |
| svg |
joc |
1.5.4 |
| vsc-python-indent |
Kev |
1.21.0 |
| dotenv |
mik |
1.0.1 |
| microsoft-testing |
ms- |
0.2.0 |
| azure-dev |
ms- |
0.10.0 |
| vscode-azure-github-copilot |
ms- |
1.0.153 |
| vscode-azure-mcp-server |
ms- |
1.0.1 |
| vscode-azureappservice |
ms- |
0.26.4 |
| vscode-azurecontainerapps |
ms- |
0.10.0 |
| vscode-azurefunctions |
ms- |
1.20.3 |
| vscode-azureresourcegroups |
ms- |
0.12.1 |
| vscode-azurestaticwebapps |
ms- |
0.13.2 |
| vscode-azurestorage |
ms- |
0.17.1 |
| vscode-azurevirtualmachines |
ms- |
0.6.10 |
| vscode-cosmosdb |
ms- |
0.30.2 |
| vscode-dotnet-runtime |
ms- |
3.0.0 |
| vscode-edge-devtools |
ms- |
2.1.10 |
| debugpy |
ms- |
2025.18.0 |
| python |
ms- |
2026.2.0 |
| vscode-pylance |
ms- |
2026.1.1 |
| vscode-python-envs |
ms- |
1.16.0 |
| remote-containers |
ms- |
0.442.0 |
| azure-repos |
ms- |
0.40.0 |
| azurecli |
ms- |
0.6.0 |
| remote-explorer |
ms- |
0.5.0 |
| remote-repositories |
ms- |
0.42.0 |
| remote-server |
ms- |
1.5.3 |
| vscode-node-azure-pack |
ms- |
1.8.0 |
| vsliveshare |
ms- |
1.0.5959 |
| windows-ai-studio |
ms- |
0.30.1 |
| autodocstring |
njp |
0.6.1 |
| chatgpt |
ope |
0.5.76 |
| oracle-java |
Ora |
25.0.1 |
| vscode-jest |
Ort |
6.4.4 |
| java |
red |
1.52.0 |
| vscode-yaml |
red |
1.20.0 |
| vscode-ai-foundry |
Tea |
0.16.0 |
| pdf |
tom |
1.2.2 |
| vscode-gradle |
vsc |
3.17.2 |
| vscode-java-debug |
vsc |
0.58.5 |
| vscode-java-dependency |
vsc |
0.27.0 |
| vscode-java-pack |
vsc |
0.30.5 |
| vscode-java-test |
vsc |
0.44.0 |
| vscode-maven |
vsc |
0.45.1 |
| quokka-vscode |
Wal |
1.0.755 |
| jinja |
who |
0.0.8 |
| vscode-import-cost |
wix |
3.3.0 |
| markdown-pdf |
yza |
1.5.0 |
| markdown-all-in-one |
yzh |
3.6.3 |
(1 theme extensions excluded)
A/B Experiments
vsliv368cf:30146710
pythonvspyt551:31249599
binariesv615:30325510
nativeloc1:31344060
dwcopilot:31170013
dwoutputs:31242946
copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
63221493:31336333
envsdeactivate2:31464701
cloudbuttont:31379625
3efgi100_wstrepl:31403338
use-responses-api:31390855
ddidtcf:31399634
je187915:31401257
ec5jj548:31422691
cp_cls_t_966_ss:31454198
c0683394:31463858
ge8j1254_inline_auto_hint_haiku:31431912
nes-autoexp-10:31446583
a5gib710:31434435
00h15499_gpt_53_codex:31464542
7a04d226_do_not_restore_last_panel_session:31438103
gpt_5_3_codex_f4456sfsd:31465102
preserve_tokens:31444547
cp_cls_c_1081:31454833
copilot-nes-oct-trt:31432596
ia-use-proxy-models-svc:31452481
a43f0574a:31442826
e9c30283:31461165
c0ci8992_validated:31449878
nes-conv-2-3:31462665
subagent_3ccgc321:31461114
idci7584:31464702
edit_mode_hidden:31461530
showstats:31457174
e3e4d672:31461204
864ei723_large_tool_results_to_disk:31460878
reg-2ge67640:31455970
nes-extended-on:31455476
chat:31457767
ah:31460422
Type: Bug
Bug Report: Copilot Agent Mode silently degrades to Ask Mode mid-task, without notification
Product: GitHub Copilot in VS Code
Mode: Agent Mode
Observed: February 2026
Description
When Copilot is running a multi-step agentic task in Agent Mode, the session silently loses tool access mid-task. The agent continues executing as if tools are available, fails silently on each tool call, and eventually falls back to producing code-block suggestions (Ask Mode behavior) — without informing the user that mode degradation has occurred.
Steps to Reproduce
manage_todo_listblocked)Expected Behavior
Actual Behavior
Impact
Evidence
Screenshot attached showing the exact failure sequence:
Tried to implement changes but todo list tool was disabledFile editing tools are disabled. I'll use the terminal to create/modify all files directly.Tried to use tools but was blockedVS Code version: Code 1.109.4 (c3a2684, 2026-02-16T15:35:57.932Z)
OS version: Windows_NT x64 10.0.22631
Modes:
System Info
GPU0: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VENDOR=Google, DRIVER_VERSION=10.0.22621.5415
GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.22621.5415
GPU2: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.22621.5415
Machine model name:
Machine model version:
direct_rendering_display_compositor: disabled_off_ok
gpu_compositing: disabled_software
multiple_raster_threads: enabled_on
opengl: disabled_off
rasterization: disabled_software
raw_draw: disabled_off_ok
skia_graphite: disabled_off
trees_in_viz: disabled_off
video_decode: disabled_software
video_encode: disabled_software
webgl: unavailable_software
webgl2: unavailable_software
webgpu: unavailable_software
webnn: unavailable_software
Extensions (74)
(1 theme extensions excluded)
A/B Experiments