feat(kitchen-sink): add mock agent event log copy

[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

[NathanFlurry]

• fix(pegboard): align drain grace defaults with stop threshold #4958 : 2 dependent PRs (#4960 , #4966 )
• fix(rivetkit): preserve bridge error messages #4959
• fix(rivetkit): fire abort signal on shutdown finalize #4957
• fix(rivetkit): use startup kv preload #4956
• fix(client): flatten skipReadyWait option #4955
• ci(publish): add manual preview publish flow #4954
• fix(depot): add ltx decode diagnostics #4953
• fix(universaldb): preserve plain set values #4952
• fix(universaldb): align versionstamp operand encoding #4951
• fix(rivetkit): export database provider types #4950
• wip: kitchen sink agentic loop finish #4949
• chore(rivetkit): note duplicate admission logic #4948
• test(rivetkit): cover bypass fetch header forwarding #4947
• feat(kitchen-sink): add actor probe controls #4946
• fix(gateway): split actor response wait errors #4945
• fix(guard): handle bypass preflight before query parse #4944
• feat(kitchen-sink): add mock agent event log copy #4943 👈 (View in Graphite)
• fix(kitchen-sink): default mock agent to local endpoint #4942
• test(rivetkit): enable driver lifecycle regressions #4941
• test(rivetkit): verify cached websocket db refs exceed grace #4940
• fix(rivetkit-core): keep sleeping actors reachable during grace #4939
• test(rivetkit): cover async websocket close db access #4938
• fix(rivetkit): keep actors awake until keepAwake work finishes #4937
• fix(rivetkit): persist native onSleep state on errors #4936
• fix(rivetkit-core): allow dispatch during sleep grace #4935
• fix(rivetkit): make duplicate sleep requests idempotent #4934
• main

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[claude]

PR Review: feat(kitchen-sink): add mock agent event log copy

Overview

This PR adds a Copy button to the Event Log panel in the kitchen-sink example's MockAgenticLoopPanel. Clicking it copies log entries to the clipboard in a tab-separated format (time\tlevel\tmessage) and shows a brief "Copied" confirmation for 1.5 seconds before resetting. The change is small, self-contained, and follows existing patterns.

---

What Works Well

• Timer cleanup: copyResetTimerRef is properly cleared in the existing unmount useEffect, preventing state updates on an unmounted component.
• Debounced reset: The timer is cancelled and restarted on each click, correctly handling rapid clicking.
• Accessible markup: The button has both aria-label and title attributes and is disabled when the log is empty.
• Correct useCallback dependency: Depends on logs, so the closure always captures the latest entries.

---

Issues

Unhandled clipboard API rejection

navigator.clipboard.writeText rejects when the page is served over HTTP (common in local dev), the user denies the clipboard permission, or the document is not focused. Currently the rejection is silently swallowed — the button appears to do nothing with no feedback to the user.

Wrap the clipboard call in a try/catch:

try {
    await navigator.clipboard.writeText(text);
    setEventLogCopied(true);
    if (copyResetTimerRef.current) clearTimeout(copyResetTimerRef.current);
    copyResetTimerRef.current = setTimeout(() => {
        setEventLogCopied(false);
        copyResetTimerRef.current = null;
    }, 1500);
} catch (err) {
    console.error("Failed to copy event log:", err);
}

---

Minor Notes

• CSS placement: New styles are added inline in index.html, consistent with the rest of the file.
• Lucide icon size: <Clipboard size={15} /> vs size={16} used elsewhere (e.g. <Trash2 size={16} />). A 1px difference is harmless but could be aligned for consistency.

---

Summary

Straightforward and well-implemented. The only actionable change is adding a try/catch around the clipboard write to handle rejections gracefully. Everything else looks good.

[github-actions]

Preview packages published to npm

Install with:

npm install rivetkit@pr-4943

All packages published as 0.0.0-pr.4943.a6ee1bd with tag pr-4943.

Engine binary is shipped via @rivetkit/engine-cli on linux-x64-musl, linux-arm64-musl, darwin-x64, and darwin-arm64. Windows users should use the release installer or set RIVET_ENGINE_BINARY.

Docker images:

docker pull rivetdev/engine:slim-a6ee1bd
docker pull rivetdev/engine:full-a6ee1bd

Individual packages

npm install rivetkit@pr-4943
npm install @rivetkit/react@pr-4943
npm install @rivetkit/rivetkit-napi@pr-4943
npm install @rivetkit/workflow-engine@pr-4943