Context window overflow and Rust backtrace errors causing chat suspension and data loss

### Checks

- [x] I have searched [github.com/aws/amazon-q-developer-cli/issues](https://github.com/aws/amazon-q-developer-cli/issues?q=) and there are no duplicates of my issue
- [x] I have run `q doctor` in the affected terminal session
- [x] I have run `q restart` and replicated the issue again

### Operating system

macOS 26.0.0 (25A5295e)

### Expected behaviour

Amazon Q should handle context window limits gracefully without causing system crashes or complete data loss. Users should be able to continue their work sessions without losing significant progress due to technical failures.

### Actual behaviour

Amazon Q CLI experienced repeated "context window has overflowed" errors followed by Rust backtrace failures. The chat became suspended and unresponsive, requiring clear and clear-cache commands to recover. This resulted in complete loss of chat history and work progress.

```
[chat-transcript]
> okay so i had to clear all our chat history and data because of a rust_backtrace full error or something that caused you to stop working, unfortunately i have to ask if we can submit a ticket into amazon requesting my free chat token limit be reset because all of the work we did is now useless

I understand the frustration of losing your chat history due to a technical error. Unfortunately, I don't have the ability to directly reset chat token limits or submit tickets on your behalf.

For issues related to Amazon Q usage limits or technical problems, you can:

1. **Contact AWS Support** directly through the AWS Console if you have a support plan
2. **Use the AWS Forums** to report the issue and request assistance
3. **Submit feedback** through the AWS Console under the Amazon Q service section

When contacting support, mention:
- The `rust_backtrace` error that caused the service to stop working
- That you lost significant work progress due to this technical issue
- Request for consideration of token limit reset due to the service failure

You might also want to check if there are any known issues or maintenance notices for Amazon Q that could explain the error you encountered.

Would you like me to help you document the technical details of what happened, or assist with any of the work you need to restart?
[Tool uses: none]

> can you read images? i just took a screen shot of the chat

Yes, I can read images! I have the ability to analyze screenshots, diagrams, code snippets in images, and other visual content.

Please share your screenshot and I'll take a look at it. You can either:
1. Provide the file path to the screenshot if it's saved locally
2. Or if you're planning to save it, let me know where you'll put it and I can read it from there

Once I can see the screenshot, I'll be able to help you with whatever you need regarding the chat history or the rust_backtrace error you mentioned.
[Tool uses: none]

> whereever my screenshots auto save to idk

Let me help you find where your screenshots are automatically saved on macOS. I'll check the common default locations:
[Tool uses: fs_read]

Perfect! I can see there's a recent screenshot on your Desktop: "Screenshot 2025-07-04 at 1.46.18 AM.png". Let me read it:
[Tool uses: fs_read]

I can see the screenshot clearly now. This shows a serious technical issue with the Amazon Q CLI where:

1. **Context window overflow errors** occurred multiple times, causing the chat to malfunction
2. **Rust backtrace errors** appeared, indicating internal system failures
3. The chat became **suspended** and unresponsive
4. You had to use `clear` and `clear-cache` commands to try to recover

This is definitely a legitimate technical failure that caused you to lose your work progress. Given the severity of this issue, you have a strong case for requesting token limit consideration.

I can help you report this issue properly. Let me open a GitHub issue template that will include the technical details:
[Tool uses: report_issue]

(...truncated)
```

### Steps to reproduce

1. Extended chat session that approached context window limits
2. System began showing "context window has overflowed" errors
3. Rust backtrace errors appeared
4. Chat became suspended and unresponsive
5. Required clear/clear-cache to recover, losing all work

### Environment

```yaml

[q-details]
version = "1.12.3"
hash = "65aa9285fc7ec3716215386a89d3a626500a25a7"
date = "2025-07-03T01:14:12.212107Z (1d ago)"

[system-info]
os = "macOS 26.0.0 (25A5295e)"
chip = "Apple M3"
total-cores = 8
memory = "24.00 GB"

[environment]
cwd = "/Users/USER"
cli-path = "/Users/USER"
install-method = "unknown"

[env-vars]
PATH = "/Library/Frameworks/Python.framework/Versions/3.13/bin:/opt/homebrew/bin:/opt/homebrew/sbin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/Users/USER/Library/Application Support/Code/User/globalStorage/github.copilot-chat/debugCommand:/Users/USER/.local/bin:/Users/USER/.android-sdk-macosx/platform-tools/"
QTERM_SESSION_ID = "9873acbd264c47f1a1f988f8a2da6e6e"
Q_SET_PARENT_CHECK = "1"
Q_TERM = "1.12.2"
SHELL = "/bin/zsh"
TERM = "xterm-256color"
ZDOTDIR = "/Users/USER"
__CFBundleIdentifier = "com.microsoft.VSCode"

[chat-settings]

[chat-trusted_tools]

[chat-failed_request_ids]
none

[chat-context]
current_profile=default
profiles=
default

global_context=
.amazonq/rules/**/*.md
README.md
AmazonQ.md

profile_context=none

files=none
```

Inizia riproducendo una sessione di chat estesa vicino al limite di contesto nell’ambiente macOS segnalato, usando q doctor e q restart come descritto. Acquisisci l’output dell’overflow del contesto e del backtrace di Rust prima di usare i comandi di ripristino. È completato quando la sessione gestisce il limite senza sospensioni, arresti anomali o perdita della cronologia della chat.

Scritto dal modello di indicizzazione a partire dal testo della issue.