## Description
Adds a postgresql custom list_roles tool, that lists all the
user-created roles in the instance. It provides details about each
role's attributes and memberships.
> Should include a concise description of the changes (bug or feature),
it's
> impact, along with a summary of the solution
![Uploading Screenshot 2025-11-26 at 1.16.42 AM.png…]()
<img width="1065" height="145" alt="Screenshot 2025-11-26 at 12 59
56 AM"
src="https://github.com/user-attachments/assets/d90131b1-d369-4108-b4db-ee5dc9aafe38"
/>
## PR Checklist
> Thank you for opening a Pull Request! Before submitting your PR, there
are a
> few things you can do to make sure it goes smoothly:
- [x] Make sure you reviewed
[CONTRIBUTING.md](https://github.com/googleapis/genai-toolbox/blob/main/CONTRIBUTING.md)
- [x] Make sure to open an issue as a
[bug/issue](https://github.com/googleapis/genai-toolbox/issues/new/choose)
before writing your code! That way we can discuss the change, evaluate
designs, and agree on the general idea
- [x] Ensure the tests and linter pass
- [x] Code coverage does not decrease (if any source code was changed)
- [x] Appropriate docs were updated (if necessary)
- [ ] Make sure to add `!` if this involve a breaking change
🛠️ Fixes #<1738>
Co-authored-by: Wenxin Du <117315983+duwenxin99@users.noreply.github.com>
