💭 Checking the PR against the previous flagged issues at commit 3905ec8 — the three fixes appear to be in place. The operation field now properly uses schema literals with a derived message, the ws.ts file correctly passes the operation from the cause, and the make function is properly exported. Now scanning the current head for new issues. There's some duplication between AgentSessionScanFailedError in AgentSessionScanner.ts and AgentSessionScanError in the contracts, with ws.ts mapping between them. This is at the RPC boundary translating an internal error to a contract error, which is acceptable, though there's a structural difference in how the cause is defined — required as a defect in the scanner versus optional in the contract. The mapError construction is inline rather than a redundant wrapper, so it's not violating the guidelines. The previous feedback about passing the operation through was addressed, so this doesn't seem like a new violation. Looking at imports in AgentSessionScanner.ts, there's a named import of ProjectionSnapshotQuery from the local service module, but the convention calls for importing the service module as a namespace and accessing its public shape that way — the test file actually follows this pattern correctly. This is a violation of the established convention. Other imports like resolveCodexHomeLayout and expandHomePath are fine as pure helpers. I should check how other server files import ProjectionSnapshotQuery to see if this is legacy code or a widespread pattern. The service definition order looks acceptable: imports, error class, Context.Service tag, type definitions, interfaces, helpers, then make and layer. Test layers for ServerSettings and ServerConfig are fine. The test file properly uses Layer.succeed with the service tag and Effect.die for unused paths. Since this is new behavior, tests are required and justified. The web-side code in agentSessions.ts is fine, and AgentSessionScanner.ts correctly uses the ["Service"] accessor pattern. Now I need to check the AgentSessionScanError contracts. Looking at the cause field in the error schema — it's marked optional with Schema.optional(Schema.Defect()), but the construction in ws.ts always passes a cause, which suggests it should be required according to the convention. That's a minor finding, though optional fields at schema boundaries might be intentional for client decoding. Let me check how other contract errors in the repo handle this pattern to understand the conventions better, then verify against the actual files at head. I'm noticing an import convention inconsistency in AgentSessionScanner.ts — it's using a named import for the service tag while its sibling ProjectSetupScriptRunner.ts and the test file both use namespace imports, which violates the pattern of importing local service modules as namespaces at service boundaries. I should also look at how the contract errors handle Schema.optional(Schema.Defect()) compared to other contract error patterns. There's a duplication issue here: AgentSessionScanFailedError in the server and AgentSessionScanError in the contracts have identical shapes, but only the contract error is the declared RPC error channel. The question is whether the scanner could just fail directly with the contract's AgentSessionScanError instead of wrapping the server error, since many services in this repo probably use contract errors directly. Let me check how filesystemBrowse handles this pattern. The filesystem browse pattern shows a consistent approach where server-internal errors get mapped to contract errors in ws.ts, which is fine. I'm noticing the duplicate error types—AgentSessionScanFailedError and AgentSessionScanError with identical fields—and while it's borderline, the mapping preserves both the operation and cause, which aligns with the guidelines. The real question is whether cause should be optional in the contract. Every construction site in ws.ts includes a cause, but during rolling upgrades when clients decode contract errors, optional might be intentional—similar to how FilesystemBrowseError handles it. I should check the full filesystem.ts implementation to see the pattern. The schema pattern with Schema.optional(Schema.Defect()) aligns with the existing conventions, so that's good. Moving through the other new files now—the web state file imports a helper function that's straightforward, and the WelcomeWizard component uses standard hooks without any Effect service complications. Checking the ws.ts changes... the AgentSessionScanner is properly yielded and its layer is provided correctly. The test file references look fine from a convention standpoint. For the error contracts, AgentSessionScanError follows the pattern with its operation discriminator, and the scanner's separate error type is acceptable. One thing to verify: in AgentSessionScanner.ts, there's a Path service being provided inside the service constructor—it's redundant since the service is already in the environment, but that's not technically a convention violation. Checking the error handling structure — AgentSessionScanFailedError is properly required, and the Context.Service interface follows the right ordering with error, tag, types, make, and layer. The main question is whether the scanner should reuse the contract error directly instead of wrapping it in a duplicate class, since the two are structurally identical, but this doesn't clearly violate the stated rules about error translation boundaries. I need to flag the import namespace violation in AgentSessionScanner.ts at line 29, but since fixing it requires coordinating changes across both the import statement and its usage at line 128, a single inline suggestion won't be self-contained. Given that this is a clear convention violation, I'll mark the check as failed.

1. modify_pr — One convention issue found in the new server service module. The three items flagged on the previous revision (redundant failure singleton on AgentSessionScanError, message-derived wrapper in ws.ts, unexported make) are all resolved.