feat(kitchen-sink): add mock agentic loop

[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]

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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• 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
• 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
• fix(rivetkit): align logs with engine logfmt #4933
• fix(ci): standardize publish rust toolchain #4931
• SPLIT UP: agentic loop test #4932
• chore(rivetkit): doc skip ready wait #4927
• fix(guard): parse gateway bypass query booleans #4926
• feat(depot-client): add vfs staging cache ttl #4930
• feat(depot-client): wire sqlite optimization flags #4923
• feat(rivetkit): support gateway bypass client overrides #4928
• test(depot-client): stabilize fault harness #4924
• chore(depot-client): split sqlite vfs transports #4922
• feat(rivetkit): support gateway bypass probes #4915
• feat(kitchen-sink): add mock agentic lifecycle loop #4914
• feat(kitchen-sink): add mock agentic loop #4891 👈 (View in Graphite)
• feat(rivetkit): support gateway bypass client requests #4917
• fix(pegboard): restore hibernating request ids #4898 : 2 other dependent PRs (#4899 , #4916 )
• chore(guard): configure local timeout knobs #4913
• docs(rivetkit): raise serverless start payload limit #4911
• test(kitchen-sink): add sqlite memory soak harness #4910
• feat(rivetkit): expose runtime diagnostics #4909
• chore(depot-client): migrate to worker thread #4907 : 2 other dependent PRs (#4912 , #4918 )
• test(driver): select matrix cells with vitest filters #4906
• fix(pegboard): restore hibernating requests on serverful start #4904 : 1 other dependent PR (#4905 )
• fix(rivetkit): drain shutdown work before sleep #4902 : 1 other dependent PR (#4903 )
• feat(sqlite): wire remote sqlite execute handlers #4897
• test(serverless): avoid pinning header validation order #4896
• chore(driver-test-runner): add native/wasm runtime matrix to skill #4884 : 3 other dependent PRs (#4892 , #4894 , #4901 )
• chroe: rename rivetkit-sqlite to depot-client #4883
• fix(rivetkit-wasm): fix mem leaks #4880
• chore(rivetkit): wasm support #4860
• feat(sqlite): add cold read benchmarks and simplify optimizations #4857
• feat(sqlite): benchmark cold reads #4848 : 1 other dependent PR (#4864 )
• docs(actors): document manual lifecycle controls #4847
• test(sqlite): expand db stress coverage #4846 : 1 other dependent PR (#4849 )
• test(raw-websocket): add serverless smoke coverage #4845
• feat(serverless): configure drain grace period #4844
• fix(publish): enable frontend build for engine target and use turbo build instead of turbo build:engine #4843
• feat(rivetkit): expose conn handle in onWebSocket context #4842
• fix(rivetkit): normalize waitUntil/keepAwake promises to null to avoid serde undefined error #4841
• fix(rivetkit): remove requirement for token #4839 : 1 other dependent PR (#4840 )
• fix(pegboard-envoy): allow sqlite requests across lifecycle states #4838
• fix(pegboard): route scoped actor key reads by runner dc #4837
• fix(sqlite-storage): let sqlite open take over stale owners #4834
• fix(engine-tests): parallelize multi-DC startup + enable 6 multi-DC tests #4833
• fix(api): honor cursor in actor_ids list path #4832
• fix(api): silently filter invalid IDs from actor_ids query instead of 400 #4831
• fix(api-peer): make actors_delete idempotent for already-destroyed actors #4830
• fix(pegboard): use Iterator streaming mode in list_names so limit param is honored #4829
• chore(engine-tests): convert envoy tests to Sleep crash policy + triage ignored #4828
• feat(engine-tests): wire envoy actor names through prepopulate_actor_names #4827
• chore(depot): fault injection tests #4868
• feat(sqlite): pitr & forking #4859 : 1 other dependent PR (#4863 )
• chore(sqlite): stateless storage refactor #4856
• main

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[claude]

PR #4891 Review: feat(kitchen-sink): add mock agentic loop

Overview

Adds a mock agentic loop example consisting of:

• Actor (src/actors/testing/mock-agentic-loop.ts): simulates LLM inference by inserting one row per second into SQLite and streaming progress over WebSocket
• Driver script (scripts/mock-agentic-loop.ts): connects via raw WebSocket, drives inference requests, verifies progress ordering, and periodically POSTs sleep keepalives
• Registry registration and a change to serverlessPoolConfig defaults

The overall design is solid for a stress/smoke test harness. A few items worth addressing.

---

Issues

Cross-connection concurrency gap (actor side)

The activeInference guard is declared inside the onWebSocket closure, making it per-connection rather than per-actor. If two WebSocket connections to the same actor both send infer with the same requestId, the opening DELETE FROM mock_agentic_entries WHERE request_id = ? from one coroutine can race with the INSERT loop of the other, producing corrupt verification results.

In the current script, requestId is always a fresh UUID so this will not trigger in normal use. A simple fix is to promote the guard to actor-level state (outside onWebSocket), or document the limitation.

serverlessPoolConfig default change is kitchen-sink-wide

The bumped defaults (requestLifespan 30 s to 900 s, drainGracePeriod 5 s to 900 s) apply to every actor routed through serverlessPoolConfig, not just the mock agentic loop. Bumping drainGracePeriod from 5 s to 15 min is a large behavioural change for all existing kitchen-sink actors. If the long lifespan is only needed for this actor, consider per-actor pool overrides or add a comment explaining the intent.

SLEEP_INTERVAL_MS is not env-configurable

Every other timing parameter has a numberFromEnv override, but SLEEP_INTERVAL_MS = 120_000 is hardcoded. This inconsistency will be confusing for anyone trying to tune the test parameters.

---

Minor / Style

Magic number 1 in send (actor file, readyState !== 1): use WebSocket.OPEN or a named constant instead of the bare literal.

started message defined but never consumed: The ServerMessage union includes { type: "started" ... } and the actor sends it, but the client script immediately starts waiting for progress/done and silently drops the started frame. A short comment noting this is intentional would help future readers.

history response grows unbounded: The actor sends the full entries array with no limit. After a long soak run the table can grow large. Consider a row cap, or drop entries from the response if totalRows alone suffices for the diagnostic.

---

What is well done

• canHibernateWebSocket: false is the right call given the active in-memory inference state, and c.keepAwake(inference) correctly prevents the actor from sleeping mid-inference.
• Errors are sent back over the WebSocket rather than silently swallowed, which is valuable for remote debugging.
• The RawSession waiter queue is clean and handles reconnect correctly.
• Input validation (positiveInteger, stringValue, numberFromEnv) at both actor and script boundaries is thorough.
• Verification via the action endpoint (a separate code path from WebSocket) cross-checks that SQLite persistence is correct, which is the core value of this test.

[NathanFlurry]

Landed in main via stack-merge fast-forward push. Commits are in main; closing to match.