Docs accuracy checks

When writing documentation in code (comments, docstrings, example snippets), ensure every instruction and external link precisely matches the actual package extras and the implemented service/provider.

Apply this checklist:

• Installation examples: use the correct pip syntax for editable installs and extras, and confirm the package name.
  • Prefer patterns like:
    • pip install -e ".[openai]"
    • pip install "db-gpt[openai]"
• External API links in comments/docstrings: only keep references that match the real backend/provider. If the code is for Google Gemini, don’t keep ZhiPu-specific API docs—update the link/title or remove it.

Example (corrected install snippet):

# Install extra support
pip install -e ".[openai]"
# or
pip install "db-gpt[openai]"

If you’re unsure which doc/link is correct, verify against the project’s packaging metadata (extras) and the exact provider SDK you’re calling.