Update README with comprehensive SDK overview and current features

[devin-ai-integration]

Update README with comprehensive SDK overview and current features

Summary

Updated the main README.md to provide a more comprehensive overview of the Codegen SDK, highlighting both AI agent capabilities and programmatic codebase manipulation features. The changes transform the README from a simple agent API introduction to a complete project overview covering three primary use cases: AI Code Agents, Codebase SDK, and SWE-Bench Evaluation.

Key changes include:

• Added detailed overview section with three primary use cases
• Updated installation instructions to emphasize uv package manager
• Added code examples for both Agent API and Codebase SDK
• Included Python 3.12-3.13 version requirements
• Added comprehensive Features section
• Expanded Resources with detailed documentation links and integrations

Review & Testing Checklist for Human

• Test all documentation links - Verify all docs.codegen.com URLs work and point to correct content (high risk of broken links)
• Verify code examples - Test the Codebase SDK examples to ensure they work with the actual API (Codebase.from_repo(), codebase.functions, etc.)
• Confirm installation instructions - Verify that uv is indeed the preferred installation method and that the commands work correctly
• Check Python version requirements - Confirm that Python 3.12-3.13 is accurate and complete based on current pyproject.toml
• Review messaging alignment - Ensure the three primary use cases accurately represent current project priorities and capabilities

Recommended test plan: Clone a fresh copy of the repository and follow the installation and getting started instructions step-by-step to ensure they work for new users.

---

Diagram

%%{ init : { "theme" : "default" }}%%
graph TD
    README["README.md"]:::major-edit
    pyproject["pyproject.toml"]:::context
    contrib["CONTRIBUTING.md"]:::context
    agents_readme["src/codegen/agents/README.md"]:::context
    docs_site["docs.codegen.com"]:::context
    
    README --> pyproject
    README --> contrib
    README --> agents_readme
    README --> docs_site
    
    pyproject -.->|"Python version requirements"| README
    contrib -.->|"uv installation method"| README
    agents_readme -.->|"Agent API examples"| README
    docs_site -.->|"Documentation links"| README
    
    subgraph Legend
        L1[Major Edit]:::major-edit
        L2[Minor Edit]:::minor-edit
        L3[Context/No Edit]:::context
    end
    
    classDef major-edit fill:#90EE90
    classDef minor-edit fill:#87CEEB
    classDef context fill:#FFFFFF

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Notes

• This PR was requested by rpatel@codegen.com in Devin session: https://app.devin.ai/sessions/87a8dc062405421c9741b9d724fa2a9d
• The update aims to make the README more comprehensive and representative of the full SDK capabilities
• Special attention should be paid to the documentation links since they were added without verification
• The code examples are illustrative and should be tested to ensure they work with the current API

[devin-ai-integration]

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