chore(rivetkit): log inspector errors + standardize pino errorKey error

[abcxff]

Adds error logs to inpector requests + standardizes error errorKey for pino (was being used but not configured in base logger)

[railway-app]

🚅 Deployed to the rivet-pr-4986 environment in rivet-frontend

Service	Status	Web	Updated (UTC)
frontend-inspector	❌ Build Failed (View Logs)	Web	May 13, 2026 at 6:38 pm
kitchen-sink	❌ Build Failed (View Logs)	Web	May 13, 2026 at 6:38 pm
frontend-cloud	🕒 Building (View Logs)	Web	May 13, 2026 at 6:37 pm
website	😴 Sleeping (View Logs)	Web	May 7, 2026 at 5:48 am
ladle	❌ Build Failed (View Logs)	Web	May 6, 2026 at 7:42 pm
mcp-hub	✅ Success (View Logs)	Web	May 6, 2026 at 7:41 pm

[abcxff]

• [slop]fix(workflow-engine): only commit step state after success #5010 : 2 dependent PRs (#5048 , #5052 )
• fix(rivetkit): decode bridge errors with actor: null #5056
• fix(rivetkit): bind methods through createWriteThroughProxy #4987
• feat(rivetkit): add ConnectionMap readonly Map wrapper for actor connections #5047
• fix(rivetkit-core): chunk apply_batch puts/deletes at 128 #5046
• fix(pegboard): validate drain_grace_period < request_lifespan #4998
• chore(rivetkit): log inspector errors + standardize pino errorKey error #4986 👈 (View in Graphite)
• fix(rivetkit): remove async drizzle db proxy #4984 : 2 other dependent PRs (#4985 , #4991 )
• main

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[claude]

Code Review: chore(rivetkit): log inspector errors + standardize pino errorKey error

Overview

This PR does two related things:

1. Adds errorKey: "error" to pino logger configs so the error field is properly serialized as a structured error object.
2. Renames catch variable err → error and log field key err: → error: throughout several files for consistency with the now-configured errorKey.

The motivation is sound — without errorKey: "error" configured, passing an Error object to the error field would not get pino's special serialization treatment (stack trace, type, etc.), making structured error logging inconsistent.

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Issues

Bug: Variable shadowing in inline-websocket-adapter.ts

The inner catch (error) shadows the outer error parameter in #handleError. The semantics are actually correct (inner logs the handler error, outer fires to both sides), but this will likely trigger a lint warning. Should rename the inner catch variable to handlerError or similar.

Incomplete rename in registry/index.ts

One catch block was only half-updated — the variable remains err but the log field was changed to error: err. All other sites in this PR rename the variable too. Looks like an oversight.

Log message capitalization in native.ts

Two of the three new log messages use sentence-case, violating the CLAUDE.md rule that log messages should be lowercase:

• "Error handling inspector action request" should be "error handling inspector action request"
• "Error handling inspector request" should be "error handling inspector request"

The third new message ("error replaying workflow history") is correctly lowercase.

Inconsistent approach in actor-driver.ts

Only the log field key is renamed (err: → error:) but the catch variable names remain err. This creates within-file inconsistency where the catch variable and the field name differ. The rest of the PR renames both together.

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Minor Notes

• Redundant fields in inline-websocket-adapter.ts: With errorKey: "error" now configured, pino will auto-serialize .message and .stack from the Error object. The explicit errorMessage and stack fields alongside error are now redundant (not wrong, just noisy).

• Pino call style: registry/index.ts mixes logger().warn({ error }, "message") and logger().warn({ msg: "...", error }). The codebase convention appears to prefer the { msg: "...", error } style.

• Deprecated runner files: Changes to engine/sdks/typescript/runner/src/mod.ts and rivetkit-typescript/packages/engine-runner/src/mod.ts are cosmetic renames only, but CLAUDE.md marks these as deprecated paths. Worth confirming this is intentional.

• actor-driver.ts stringifyError calls: Most other sites now pass the raw Error object, but actor-driver.ts still stringifies before logging. If stringifyError returns a plain string, pino will not apply error serialization to it. Likely intentional for cleanup paths, but worth double-checking.

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Summary

The core change (adding errorKey: "error" + field name standardization) is correct and worthwhile. Main items to address before merging:

1. Rename inner catch variable in #handleError to avoid shadowing (handlerError)
2. Complete the variable rename in the registry/index.ts mode-B shutdown catch block
3. Lowercase the two new log messages in native.ts

[abcxff]

Merge activity

• May 13, 6:35 PM UTC: A user started a stack merge that includes this pull request via Graphite.
• May 13, 6:38 PM UTC: Graphite rebased this pull request as part of a merge.
• May 13, 6:39 PM UTC: @abcxff merged this pull request with Graphite.