{"record":{"id":"71cb1d8bf64411dd","repo":"slopus/happy","slug":"the-chosen-rewind-point-is-no-longer-present-in-th-71cb1d","errorCode":null,"errorMessage":"The chosen rewind point is no longer present in the source Codex thread — try forking without truncation","messagePattern":"The chosen rewind point is no longer present in the source Codex thread — try forking without truncation","errorType":"exception","errorClass":"Error","httpStatus":null,"severity":"error","filePath":"packages/happy-cli/src/api/apiMachine.ts","lineNumber":312,"sourceCode":"                    points: listCodexRewindPoints(thread),\n                };\n            });\n        });\n\n        this.rpcHandlerManager.registerHandler('codex-duplicate-thread', async (params: any) => {\n            const directory = requireNonEmptyString(params?.directory, 'directory');\n            const codexThreadId = requireNonEmptyString(params?.codexThreadId, 'codexThreadId');\n            const cutAfterItemId = requireNonEmptyString(params?.cutAfterItemId, 'cutAfterItemId');\n\n            try {\n                return await withCodexAppServerClient((client) => forkCodexThread(client, {\n                    threadId: codexThreadId,\n                    cwd: directory,\n                    cutAfterItemId,\n                }));\n            } catch (error) {\n                if (error instanceof CodexForkRewindPointNotFoundError) {\n                    throw new Error(\n                        'The chosen rewind point is no longer present in the source Codex thread — try forking without truncation',\n                    );\n                }\n                throw error;\n            }\n        });\n\n        // Register stop daemon handler\n        this.rpcHandlerManager.registerHandler('stop-daemon', () => {\n            logger.debug('[API MACHINE] Received stop-daemon RPC request');\n\n            // Trigger shutdown callback after a delay\n            setTimeout(() => {\n                logger.debug('[API MACHINE] Initiating daemon shutdown from RPC');\n                requestShutdown();\n            }, 100);\n\n            return { message: 'Daemon stop request acknowledged, starting shutdown sequence...' };","sourceCodeStart":294,"sourceCodeEnd":330,"githubUrl":"https://github.com/slopus/happy/blob/b824cd0a4681d41af631a8e422a813873e4455b0/packages/happy-cli/src/api/apiMachine.ts#L294-L330","documentation":"This error is thrown by the Codex fork RPC handler in setRPCHandlers when the underlying Codex SDK raises CodexForkRewindPointNotFoundError. It means the item the user selected as a rewind point (identified by cutAfterItemId) no longer exists in the source Codex thread, so the fork-with-truncation cannot be performed. The library re-maps the SDK error to a user-actionable message suggesting forking without truncation.","triggerScenarios":"Calling the fork/resume RPC for a Codex thread with a cutAfterItemId whose item has been removed, compacted away, or belongs to a different/older thread state; the source thread was truncated or garbage-collected between listing and forking.","commonSituations":"User picks a rewind point from a stale session list; the Codex thread was compacted/trimmed since the UI snapshot was taken; concurrent edits to the same thread from another machine; pointing at a thread ID that was recreated.","solutions":["Retry the fork without passing cutAfterItemId so the whole thread is forked instead of truncated","Re-fetch the current thread items and let the user pick a rewind point that still exists","Restart or re-open the session to get a fresh thread state, then fork again"],"exampleFix":"// before\nawait machine.forkSession({ threadId, cutAfterItemId: staleItemId });\n// after\ntry {\n  await machine.forkSession({ threadId, cutAfterItemId: staleItemId });\n} catch {\n  await machine.forkSession({ threadId }); // fork without truncation\n}","handlingStrategy":"fallback","validationCode":"// Verify the rewind point still exists before forking\nconst items = await getThreadItems(threadId);\nif (!items.some(i => i.id === cutAfterItemId)) {\n  cutAfterItemId = undefined; // fork without truncation\n}","typeGuard":"function hasRewindPoint(items: { id: string }[], id?: string): boolean {\n  return typeof id !== 'string' || items.some(i => i.id === id);\n}","tryCatchPattern":"try {\n  await forkSession({ threadId, cutAfterItemId });\n} catch (e) {\n  if (e.message.includes('rewind point is no longer present')) {\n    await forkSession({ threadId }); // fallback: no truncation\n  } else throw e;\n}","preventionTips":["Re-fetch thread items immediately before offering rewind points","Refresh the session list before fork operations","Default to full-thread fork when the selected item may be stale"],"tags":["codex","session-fork","stale-state","rpc"],"backgroundTag":"rewind-point-not-found","analyzedSha":"b824cd0a4681d41af631a8e422a813873e4455b0","analyzedAt":"2026-08-31T23:12:36.205Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-08T05:18:18.240Z"}