refactor: consolidate cross-module code duplication

src/agents/custom-agent-summaries.ts

@@ -1,3 +1,4 @@
+import { isRecord } from "../shared/record-type-guard"
 import { truncateDescription } from "../shared/truncate-description"
 import type { AgentPromptMetadata } from "./types"
 
@@ -14,9 +15,6 @@ function sanitizeMarkdownTableCell(value: string): string {
     .trim()
 }
 
-function isRecord(value: unknown): value is Record<string, unknown> {
-  return typeof value === "object" && value !== null
-}
 
 export function parseRegisteredAgentSummaries(input: unknown): RegisteredAgentSummary[] {
   if (!Array.isArray(input)) return []

src/features/background-agent/error-helpers.ts

@@ -1,19 +1,6 @@
+import { isRecord } from "../../shared/record-type-guard"
 import type { EventProperties } from "./manager"
 
-export function formatDuration(start: Date, end?: Date): string {
-  const duration = (end ?? new Date()).getTime() - start.getTime()
-  const seconds = Math.floor(duration / 1000)
-  const minutes = Math.floor(seconds / 60)
-  const hours = Math.floor(minutes / 60)
-
-  if (hours > 0) {
-    return `${hours}h ${minutes % 60}m ${seconds % 60}s`
-  }
-  if (minutes > 0) {
-    return `${minutes}m ${seconds % 60}s`
-  }
-  return `${seconds}s`
-}
 
 export function getErrorText(error: unknown): string {
   if (!error) return ""
@@ -37,9 +24,6 @@ export function isAbortedSessionError(error: unknown): boolean {
   return message.toLowerCase().includes("aborted")
 }
 
-export function isRecord(value: unknown): value is Record<string, unknown> {
-  return typeof value === "object" && value !== null
-}
 
 export function getSessionErrorMessage(
   properties: EventProperties,

src/features/background-agent/manager.ts

@@ -3,11 +3,10 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import type { BackgroundTaskConfig, TmuxConfig } from "../../config/schema"
 import { getAgentToolRestrictions, log, normalizeSDKResponse, promptWithModelSuggestionRetry } from "../../shared"
-import { setSessionTemperature } from "../../shared/session-temperature-store"
-import { setSessionTools } from "../../shared/session-tools-store"
+import { formatDuration } from "../../shared/format-duration"
+import { setSessionTemperature, setSessionTools } from "../../shared/session-state"
 import { isInsideTmux } from "../../shared/tmux"
 import { subagentSessions } from "../session-state"
-
 import { getTaskToastManager } from "../task-toast-manager"
 import { ConcurrencyManager } from "./concurrency"
 import {
@@ -21,10 +20,9 @@ import {
   TASK_TTL_MS,
 } from "./constants"
 import {
-  formatDuration,
   getSessionErrorMessage,
   isAbortedSessionError,
-} from "./error-helpers"
+  } from "./error-helpers"
 import {
   type CircuitBreakerSettings,
   detectRepetitiveToolUse,

src/features/task-toast-manager/types.ts

@@ -1,11 +1,11 @@
-import type { ModelSource } from "../../shared/model-resolver"
+import type { ModelResolutionProvenance } from "../../shared/model-resolution-pipeline"
 
 export type TaskStatus = "running" | "queued" | "completed" | "error"
 
 export interface ModelFallbackInfo {
   model: string
   type: "user-defined" | "inherited" | "category-default" | "system-default"
-  source?: ModelSource
+  source?: ModelResolutionProvenance
 }
 
 export interface TrackedTask {

src/features/tmux-subagent/session-created-event.ts

@@ -1,8 +1,7 @@
+import { isRecord } from "../../shared/record-type-guard"
+
 type UnknownRecord = Record<string, unknown>
 
-function isRecord(value: unknown): value is UnknownRecord {
-  return typeof value === "object" && value !== null
-}
 
 function getNestedRecord(value: unknown, key: string): UnknownRecord | undefined {
   if (!isRecord(value)) return undefined

src/hooks/anthropic-context-window-limit-recovery/aggressive-truncation-strategy.ts

@@ -1,6 +1,6 @@
+import { formatBytes } from "../../shared/format-bytes"
 import { log } from "../../shared/logger"
 import type { Client } from "./client"
-import { formatBytes } from "./message-builder"
 import { clearSessionState } from "./state"
 import { truncateUntilTargetTokens } from "./storage"
 import type { AutoCompactState } from "./types"

src/hooks/anthropic-context-window-limit-recovery/message-builder.ts

@@ -140,11 +140,6 @@ export async function sanitizeEmptyMessagesBeforeSummarize(
   return fixedCount
 }
 
-export function formatBytes(bytes: number): string {
-  if (bytes < 1024) return `${bytes}B`
-  if (bytes < 1024 * 1024) return `${(bytes / 1024).toFixed(1)}KB`
-  return `${(bytes / (1024 * 1024)).toFixed(1)}MB`
-}
 
 export async function getLastAssistant(
   sessionID: string,

src/hooks/anthropic-context-window-limit-recovery/tool-part-types.ts

@@ -1,3 +1,4 @@
+import type { TaskStatus } from "../../shared/status-types"
 export interface StoredToolPart {
 	id: string
 	sessionID: string
@@ -6,7 +7,7 @@ export interface StoredToolPart {
 	callID: string
 	tool: string
 	state: {
-		status: "pending" | "running" | "completed" | "error"
+		status: TaskStatus
 		input: Record<string, unknown>
 		output?: string
 		error?: string

src/hooks/architect/event-handler.ts

@@ -2,9 +2,9 @@ import type { PluginInput } from "@opencode-ai/plugin"
 import { clearMissionState, getPlanProgress, readMissionState } from "../../features/mission-state"
 import { subagentSessions } from "../../features/session-state"
 import { getAgentConfigKey } from "../../shared/agent-display-names"
+import { isAbortError } from "../../shared/is-abort-error"
 import { log } from "../../shared/logger"
 import { HOOK_NAME } from "./hook-name"
-import { isAbortError } from "./is-abort-error"
 import { injectMissionContinuation } from "./mission-continuation-injector"
 import { getLastAgentFromSession } from "./session-last-agent"
 import type { ArchitectHookOptions, SessionState } from "./types"

src/hooks/auto-slash-command/detector.ts

@@ -1,4 +1,4 @@
-import { CODE_BLOCK_PATTERN } from "../../shared"
+import { CODE_BLOCK_PATTERN } from "../../shared/code-patterns"
 import {
   EXCLUDED_COMMANDS,
   SLASH_COMMAND_PATTERN,

src/hooks/auto-slash-command/executor.ts

@@ -10,9 +10,9 @@ import {
   parseFrontmatter,
   resolveCommandsInText,
   resolveFileReferencesInText,
-  sanitizeModelField,
 } from "../../shared"
 import { isMarkdownFile } from "../../shared/file-utils"
+import { sanitizeModelField } from "../../shared/model-sanitizer"
 import type { ParsedSlashCommand } from "./types"
 
 interface CommandScope {

src/hooks/hashline-edit-diff-enhancer/hook.ts

@@ -1,4 +1,5 @@
-import { isWriteTool, log } from "../../shared"
+import { log } from "../../shared"
+import { isWriteTool } from "../../shared/tool-guards"
 import { countLineDiffs, generateUnifiedDiff } from "../../tools/hashline-edit/diff-utils"
 
 interface HashlineEditDiffEnhancerConfig {

src/hooks/hashline-read-enhancer/hook.ts

@@ -1,5 +1,5 @@
 import type { PluginInput } from "@opencode-ai/plugin"
-import { isReadTool, isWriteTool } from "../../shared"
+import { isReadTool, isWriteTool } from "../../shared/tool-guards"
 import { computeLineHash } from "../../tools/hashline-edit/hash-computation"
 
 const WRITE_SUCCESS_MARKER = "File written successfully."

src/hooks/keyword-detector/constants.ts

@@ -1,4 +1,4 @@
-export { CODE_BLOCK_PATTERN, INLINE_CODE_PATTERN } from "../../shared"
+export { CODE_BLOCK_PATTERN, INLINE_CODE_PATTERN } from "../../shared/code-patterns"
 export { ANALYZE_MESSAGE, ANALYZE_PATTERN } from "./analyze"
 export { SEARCH_MESSAGE, SEARCH_PATTERN } from "./search"
 // Re-export from submodules

src/hooks/matrix-loop/with-timeout.ts

@@ -1,20 +1 @@
-export async function withTimeout<TData>(
-	promise: Promise<TData>,
-	timeoutMs: number,
-): Promise<TData> {
-	let timeoutId: ReturnType<typeof setTimeout> | undefined
-
-	const timeoutPromise = new Promise<never>((_, reject) => {
-		timeoutId = setTimeout(() => {
-			reject(new Error("API timeout"))
-		}, timeoutMs)
-	})
-
-	try {
-		return await Promise.race([promise, timeoutPromise])
-	} finally {
-		if (timeoutId !== undefined) {
-			clearTimeout(timeoutId)
-		}
-	}
-}
+export { withTimeout } from "../../shared/with-timeout"

src/hooks/preemptive-compaction-degradation-monitor.ts

@@ -45,23 +45,7 @@ export interface AssistantCompactionMessageInfo {
   id?: string
 }
 
-async function withTimeout<TValue>(
-  promise: Promise<TValue>,
-  timeoutMs: number,
-  errorMessage: string,
-): Promise<TValue> {
-  let timeoutID: unknown
-
-  const timeoutPromise = new Promise<never>((_, reject) => {
-    timeoutID = setTimeout(() => {
-      reject(new Error(errorMessage))
-    }, timeoutMs)
-  })
-
-  return await Promise.race([promise, timeoutPromise]).finally(() => {
-    clearTimeout(timeoutID)
-  })
-}
+import { withTimeout } from "../shared/with-timeout"
 
 export function createPostCompactionDegradationMonitor(args: {
   client: ClientLike

src/hooks/preemptive-compaction-trigger.ts

@@ -17,23 +17,7 @@ const PREEMPTIVE_COMPACTION_COOLDOWN_MS = 60_000
 declare function setTimeout(handler: () => void, timeout?: number): unknown
 declare function clearTimeout(timeoutID: unknown): void
 
-async function withTimeout<TValue>(
-  promise: Promise<TValue>,
-  timeoutMs: number,
-  errorMessage: string,
-): Promise<TValue> {
-  let timeoutID: unknown
-
-  const timeoutPromise = new Promise<never>((_, reject) => {
-    timeoutID = setTimeout(() => {
-      reject(new Error(errorMessage))
-    }, timeoutMs)
-  })
-
-  return await Promise.race([promise, timeoutPromise]).finally(() => {
-    clearTimeout(timeoutID)
-  })
-}
+import { withTimeout } from "../shared/with-timeout"
 
 export async function runPreemptiveCompactionIfNeeded(args: {
   ctx: PreemptiveCompactionContext

src/hooks/read-image-resizer/hook.ts

@@ -1,6 +1,7 @@
 import type { PluginInput } from "@opencode-ai/plugin"
-import { isReadTool, log } from "../../shared"
-import { getSessionModel } from "../../shared/session-model-state"
+import { log } from "../../shared"
+import { getSessionModel } from "../../shared/session-state"
+import { isReadTool } from "../../shared/tool-guards"
 import { parseImageDimensions } from "./image-dimensions"
 import { calculateTargetDimensions, resizeImage } from "./image-resizer"
 import type { ImageAttachment, ImageDimensions } from "./types"

src/hooks/read-image-resizer/image-resizer.ts

@@ -1,4 +1,5 @@
 import { log } from "../../shared"
+import { getErrorMessage } from "../../shared/error-formatting"
 import { extractBase64Data } from "../../tools/look-at/mime-type-inference"
 import { resizeImageFallback } from "./png-fallback-resizer"
 import type { ImageDimensions, ResizeResult } from "./types"
@@ -75,9 +76,6 @@ async function renderResizedBuffer(args: {
     .toBuffer()
 }
 
-function getErrorMessage(error: unknown): string {
-  return error instanceof Error ? error.message : String(error)
-}
 
 function loadSharpModule(): Promise<unknown | null> {
   return Function('return import("sharp").catch(() => null)')() as Promise<unknown | null>

src/hooks/runtime-fallback/event-handler.ts

@@ -1,3 +1,4 @@
+import { isAbortError } from "../../shared/is-abort-error"
 import { log } from "../../shared/logger"
 import type { AutoRetryHelpers } from "./auto-retry"
 import { HOOK_NAME } from "./constants"
@@ -6,7 +7,6 @@ import { resolveFallbackBootstrapModel } from "./fallback-bootstrap-model"
 import { getFallbackModelsForSession } from "./fallback-models"
 import { dispatchFallbackRetry } from "./fallback-retry-dispatcher"
 import { createFallbackState } from "./fallback-state"
-import { isAbortError } from "./is-abort-error"
 import { SessionCategoryRegistry } from "./session-category-registry"
 import { createSessionStatusHandler } from "./session-status-handler"
 import type { HookDeps } from "./types"

src/hooks/runtime-fallback/session-messages.ts

@@ -1,3 +1,4 @@
+import { isRecord } from "../../shared/record-type-guard"
 export type SessionMessagePart = {
   type?: string
   text?: string
@@ -8,9 +9,6 @@ export type SessionMessage = {
   parts?: SessionMessagePart[]
 }
 
-function isRecord(value: unknown): value is Record<string, unknown> {
-  return typeof value === "object" && value !== null
-}
 
 function isSessionMessage(value: unknown): value is SessionMessage {
   return isRecord(value)

src/hooks/runtime-fallback/visible-assistant-response.ts

@@ -1,3 +1,4 @@
+import { isRecord } from "../../shared/record-type-guard"
 import type { extractAutoRetrySignal } from "./error-classifier"
 import type { SessionMessage, SessionMessagePart } from "./session-messages"
 import { extractSessionMessages } from "./session-messages"
@@ -55,7 +56,7 @@ export function hasVisibleAssistantResponse(extractAutoRetrySignalFn: typeof ext
 
         const infoParts = message.info?.parts
         const infoMessageParts = Array.isArray(infoParts)
-          ? infoParts.filter((part): part is SessionMessagePart => typeof part === "object" && part !== null)
+          ? infoParts.filter((part): part is SessionMessagePart => isRecord(part))
           : undefined
         const parts = message.parts && message.parts.length > 0
           ? message.parts

src/hooks/session-recovery/types.ts

@@ -1,3 +1,4 @@
+import type { TaskStatus } from "../../shared/status-types"
 
 export interface StoredMessageMeta {
   id: string
@@ -29,7 +30,7 @@ export interface StoredToolPart {
   callID: string
   tool: string
   state: {
-    status: "pending" | "running" | "completed" | "error"
+    status: TaskStatus
     input: Record<string, unknown>
     output?: string
     error?: string

src/hooks/think-mode/detector.ts

@@ -1,4 +1,4 @@
-import { CODE_BLOCK_PATTERN, INLINE_CODE_PATTERN } from "../../shared"
+import { CODE_BLOCK_PATTERN, INLINE_CODE_PATTERN } from "../../shared/code-patterns"
 
 const ENGLISH_PATTERNS = [
   /\bultrathink\b/i,

src/hooks/unstable-agent-babysitter/task-message-analyzer.ts

@@ -1,4 +1,5 @@
 import type { BackgroundTask } from "../../features/background-agent"
+import { isRecord } from "../../shared/record-type-guard"
 
 export const THINKING_SUMMARY_MAX_CHARS = 500 as const
 
@@ -20,9 +21,6 @@ function hasData(value: unknown): value is { data?: unknown } {
   return typeof value === "object" && value !== null && "data" in value
 }
 
-function isRecord(value: unknown): value is Record<string, unknown> {
-  return typeof value === "object" && value !== null
-}
 
 export function getMessageInfo(value: unknown): MessageInfo | undefined {
   if (!isRecord(value)) return undefined