Copilot Agents fails to start sessions with `GitHubLoginFailed` and `Timed out waiting for session commit`

Type: Bug

Window: Agents

# Copilot Agents fails to start sessions with `GitHubLoginFailed` and `Timed out waiting for session commit`

## Summary

The new **Copilot Agents** experience consistently fails to start any new session. Every prompt results in the Agent failing before processing begins.

Regular GitHub authentication appears valid, Copilot Student is active, network diagnostics pass, and the project is a valid Git repository.

---

## Environment

**VS Code**

* Version: **1.127.0**
* Commit: `4fe60c8b1cdac1c4c174f2fb180d0d758272d713`

**GitHub Copilot Chat**

* Version: **0.55.0 (prod)**

**Operating System**

* Windows 11
* Build `10.0.26200`
* x64

**GitHub Account**

* `EvanGribar`

**Copilot Plan**

* GitHub Copilot Student (active)

---

## Expected behavior

Opening the new Copilot Agents window and submitting a prompt should create a session and begin responding.

---

## Actual behavior

Every prompt fails immediately.

The Agent never starts processing.

The logs show authentication/session initialization failures.

---

## Relevant log output

```
GitHubLoginFailed
```

```
Failed to send first chat for session...
Error: Timed out waiting for session commit
```

```
Failed to send request:
Error: Timed out waiting for session commit
```

Additional internal errors:

```
CodeExpectedError: GitHubLoginFailed
```

```
An unknown error occurred. Please consult the log for more details.
```

There are also repeated UI lifecycle errors such as:

```
Trying to add a disposable to a DisposableStore that has already been disposed of.
```

---

## Network diagnostics

All Copilot connectivity tests succeed.

GitHub endpoints return HTTP 200:

* api.github.com
* api.individual.githubcopilot.com
* proxy.individual.githubcopilot.com
* telemetry endpoints

No proxy configured.

Electron fetch succeeds.

Node HTTPS succeeds.

Network diagnostics indicate no firewall or connectivity issue.

---

## Repository information

Originally the project was not initialized as Git.

I initialized it using:

```bash
git init
```

Repository is now recognized correctly by VS Code.

The problem persists after Git initialization.

---

## Troubleshooting performed

* Restarted VS Code
* Reloaded window
* Restarted extension host
* Signed out/in of GitHub
* Verified Copilot Student subscription is active
* Verified GitHub authentication
* Verified network connectivity
* Initialized Git repository
* Verified Git is functioning
* Confirmed no firewall/proxy issues
* Confirmed Copilot account has available usage

None resolved the issue.

---

## Additional observations

The logs show the Agent attempting to create a session but failing before the first request is committed.

This appears related to session initialization rather than network connectivity.

The failure occurs before any model response is generated.

---

## Possible regression

This appears to be related specifically to the **new Copilot Agents experience** rather than standard Copilot authentication.

The failure occurs during session creation:

```
Timed out waiting for session commit
```

followed by

```
GitHubLoginFailed
```

This may indicate an authentication/session state regression in the current Copilot Agents implementation.

---

## Reproduction steps

1. Open VS Code.
2. Open a Git repository.
3. Open the new Copilot Agents window.
4. Start a new Agent session.
5. Enter any prompt.
6. Observe that the Agent fails immediately.
7. Logs report `GitHubLoginFailed` and `Timed out waiting for session commit`.

---

## Impact

The new Copilot Agents feature is currently unusable.

Standard GitHub connectivity appears healthy, and the account is properly licensed, but no Agent session can be created.

VS Code version: Code 1.127.0 (4fe60c8b1cdac1c4c174f2fb180d0d758272d713, 2026-06-30T10:52:33+02:00)
OS version: Windows_NT x64 10.0.26200
Modes:

System Info

|Item|Value|
|---|---|
|CPUs|AMD Ryzen 5 5600X 6-Core Processor (12 x 3700)|
|GPU Status|2d_canvas: enabled
GPU0: VENDOR= 0x10de, DEVICE=0x2882 [NVIDIA GeForce RTX 4060], DRIVER_VENDOR=NVIDIA, DRIVER_VERSION=32.0.16.1047 *ACTIVE*
GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8521
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)|15.91GB (2.37GB free)|
|Process Argv|--crash-reporter-id f5655032-c162-4875-aaad-f2dd2025b238|
|Screen Reader|no|
|VM|0%|
Extensions: none
A/B Experiments

```
vsliv368:30146709
vswsl492cf:30256860
binariesv615:30325510
nativeloc1:31344060
dwcopilot:31170013
dwoutputs:31242946
copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
82j33506:31327384
6abeh943:31336334
envsactivate1:31538736
cloudbuttont:31379625
3efgi100_wstrepl:31403338
ddidt:31399633
ec5jj548:31422691
cp_cls_t_966_ss:31526232
4je02754:31466945
8hhj4413:31478653
38bie571_auto:31429954
cp_cls_t_1081:31454832
conptydll_true:31498968
ia-use-proxy-models-svc:31452481
e9c30283:31461165
test_treatment2:31471001
46204921:31447328
capi_bxe_098a3278:31544980
idci7584:31464702
e3e4d672:31494082
ei9d7968:31496641
nes-extended-on:31455476
chat:31457767
8hig5102:31480529
89g7j272:31518289
7e187181:31503455
i2gc6536:31499202
52612955:31516516
ghj88844:31499326
h08i8180_copy:31475368
ddid_c:31478207
hmra_i5g22:31518061
7df3h592:31512476
cp_cls_t_1082:31535311
logging_enabled_new:31498466
j0d79568:31499440
jb_cp_cls_t_632:31543129
56dj4588:31512888
32d76977:31512328
ha629193:31508444
cdk-lw-on:31524445
f9bf7985:31543584
a1ije391_t:31540920
41836166:31537719
jbcp_cls_pctr_t:31531130
61138546:31518536
cp_intellij_t_nes:31548657
gf14b233:31526830
nes-curr-leftover-1500:31538366
h561g132:31533256
sessions_5:31532894
ihg5j128:31534457
jh7i3328:31546038
7g2b5551:31542111
nes-ex-cf-euporie-03:31542868
nes-nc-nf-2k:31546582

```

Start in VS Code 1.127.0 with a Git repository, open the Copilot Agents window, and reproduce the failure using the listed steps. Inspect the logs around GitHubLoginFailed, session commit timeout, and DisposableStore errors; done means a new Agent session starts and processes its first prompt without these failures.

Written by the indexing model from the issue text.