feat: implement actor sandbox example

[NathanFlurry]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[railway-app]

🚅 Deployed to the rivet-pr-4140 environment in rivet-frontend

Service	Status	Web	Updated (UTC)
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[NathanFlurry]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• feat: implement actor sandbox example #4140 👈 (View in Graphite)
• chore: migrate sqlite vfs to native rust #4143
• chore: move sqlite-vfs to separate package #4142
• feat: sqlite #3666
• feat: use cases #4100 : 1 other dependent PR (#4124 )
• feat(dashboard): traces timeline ui #4056 : 1 other dependent PR (#4081 )
• fix(traces): separate entrypoints #4119 : 1 other dependent PR (#4126 )
• refactor(rivetkit): migrate granularly to zod v4 #4121
• fix(rivekit): stub traces in browser #4120
• main

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[claude]

Pull Request Review: Actor Sandbox Example

Summary

This PR consolidates multiple sandbox examples (queue-sandbox, workflow-sandbox, and their Vercel variants) into a single unified sandbox example. This is a major refactoring that demonstrates comprehensive RivetKit actor features in one place.

Overall Assessment: ✅ Approved with Minor Suggestions

The code quality is excellent, the consolidation is well-executed, and the comprehensive testing (as evidenced by todo.md) shows thoroughness. Below are some observations and suggestions.

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🟢 Strengths

1. Excellent Code Organization

• Clean separation of concerns with actors grouped by feature area (actions/, state/, lifecycle/, etc.)
• Consistent file naming and structure across all actor implementations
• Well-organized registry that clearly maps to UI navigation structure

2. Comprehensive Coverage

• Covers all major RivetKit features: actions, state, connections, HTTP/WebSocket, lifecycle, queues, workflows, and AI
• 72 actors demonstrating different patterns and use cases
• Excellent variety of examples from basic (counter) to advanced (workflows, AI agents)

3. Good Code Quality

• Proper TypeScript typing throughout
• Clean, readable implementations
• Good use of RivetKit patterns and conventions
• No obvious security concerns (no eval, innerHTML, or dangerous patterns detected)

4. Thorough Testing

• The todo.md shows comprehensive manual testing of all 79 screens
• All bugs discovered during testing were fixed before PR submission
• Good discipline in tracking and resolving issues

5. Documentation

• README.md follows the template structure correctly
• Clear explanation of features and implementation
• Proper GitHub source code links

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🟡 Suggestions for Improvement

1. Missing Vercel Example Generation

Based on CLAUDE.md guidelines, when adding new examples you should run ./scripts/vercel-examples/generate-vercel-examples.ts to create the Vercel equivalent, or add "skipVercel": true to package.json if intentionally skipped.

2. Missing Test Files

The example has no automated test files (*.test.ts, *.spec.ts). While manual testing was thorough, consider adding:

• Unit tests for key actor behaviors
• Integration tests for critical workflows
• This would help prevent regressions as the codebase evolves

3. Large Frontend Files

• frontend/App.tsx: 810 lines
• frontend/page-data.ts: 1054 lines

Suggestion: Consider breaking these into smaller, more maintainable modules.

4. Error Handling in AI Agent

In src/actors/ai/ai-agent.ts, the generateText call could fail (network issues, API errors, quota exceeded). Consider adding try-catch with proper error logging.

5. Type Safety in Raw HTTP Actor

In src/actors/http/raw-http.ts:68, the rawHttpVoidReturnActor uses as any to suppress type checking. If this is intentionally testing error handling, add a comment explaining what error is expected.

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🔴 Issues to Address

1. Empty Placeholder Files

Several files show as 0 additions/0 deletions in the PR diff:

• examples/sandbox/src/actors/workflow/_helpers.ts
• examples/sandbox/frontend/main.tsx
• examples/sandbox/src/server.ts

Question: If these files were moved from other examples and already exist, that's fine. But please verify they have the expected content and all imports resolve correctly.

2. Missing fdb-tuple-shim.mjs Context

The file src/fdb-tuple-shim.mjs was added but without explanation. Is this shim necessary? If so, add a comment explaining its purpose. If not used, remove it.

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Performance Considerations

State Management ✅

Most actors properly use state for persistence with minimal footprint and proper use of KV for large payloads.

Queue Usage ✅

Queue implementations look efficient with proper use of limits, good timeout handling, and no obvious resource leaks.

Workflow Patterns ✅

Workflow implementations follow best practices with proper use of steps for deterministic replay and clean loop breaking logic.

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Security Considerations

✅ No security issues detected:

• No use of eval, Function(), innerHTML, or dangerouslySetInnerHTML
• No environment variables exposed
• Proper input validation in most places
• State is properly scoped to actors

Minor note: The AI agent actor relies on OpenAI API key being set. Documentation properly notes this.

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Testing Coverage

Based on todo.md, all 79 screens were manually tested and 6 bugs were found and fixed. Recommendation: Convert this manual testing checklist into automated tests to prevent regressions.

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Documentation

README.md follows EXAMPLE_TEMPLATE.md structure correctly with all required sections and proper GitHub source code links.

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Code Style Compliance

Checked against CLAUDE.md guidelines:

✅ Correct:

• TypeScript usage throughout
• Proper imports (no glob imports)
• Lowercase log messages
• Structured logging with c.log.info({...}) pattern in workflows

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Recommendations

High Priority

1. Verify empty placeholder files have content or remove unused imports
2. Run Vercel example generation script or add skipVercel flag
3. Add error handling to AI agent

Medium Priority

4. Consider breaking up large frontend files
5. Add automated tests for core actor behaviors
6. Document or remove fdb-tuple-shim.mjs

Low Priority

7. Add high-level comments to actors missing them
8. Consider extracting common patterns into shared utilities

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Conclusion

This is an excellent consolidation PR that improves the examples structure significantly. The code quality is high, the testing was thorough, and the implementation demonstrates RivetKit features comprehensively.

Once the empty files are verified and Vercel generation is addressed, this PR is ready to merge.

Great work on the comprehensive testing and bug fixing during implementation! 🎉

[graphite-app]

Merge activity

• Feb 6, 8:22 AM UTC: NathanFlurry added this pull request to the Graphite merge queue.
• Feb 6, 8:23 AM UTC: CI is running for this pull request on a draft pull request (#4146) due to your merge queue CI optimization settings.
• Feb 6, 8:24 AM UTC: Merged by the Graphite merge queue via draft PR: #4146.