feat(KB-184): add model presets for task creation

- Add model preset types and settings fields with API validation
- Create model preset utility helpers for size-based auto-selection
- Add settings UI for managing model presets (create, edit, delete)
- Integrate preset selection into NewTaskModal with custom override option
- Add inline preset selection to InlineCreateCard component
- Persist modelPresetId in task store and preserve through archive/unarchive
- Add changeset and update AGENTS.md with feature documentation

packages/core/src/index.ts

@@ -1,5 +1,5 @@
 export { COLUMNS, COLUMN_LABELS, COLUMN_DESCRIPTIONS, VALID_TRANSITIONS, DEFAULT_SETTINGS, THINKING_LEVELS, THEME_MODES, COLOR_THEMES } from "./types.js";
-export type { Column, IssueInfo, IssueState, PrInfo, PrStatus, Task, TaskAttachment, TaskCreateInput, TaskDetail, AgentLogEntry, AgentLogType, AgentRole, BoardConfig, MergeResult, Settings, TaskStep, StepStatus, TaskLogEntry, ActivityLogEntry, ActivityEventType, ThinkingLevel, SteeringComment, ThemeMode, ColorTheme, PlanningQuestion, PlanningSummary, PlanningResponse, PlanningQuestionType, ArchivedTaskEntry, BatchStatusRequest, BatchStatusResponse, BatchStatusEntry, BatchStatusResult } from "./types.js";
+export type { Column, IssueInfo, IssueState, PrInfo, PrStatus, Task, TaskAttachment, TaskCreateInput, TaskDetail, AgentLogEntry, AgentLogType, AgentRole, BoardConfig, MergeResult, Settings, TaskStep, StepStatus, TaskLogEntry, ActivityLogEntry, ActivityEventType, ThinkingLevel, SteeringComment, ThemeMode, ColorTheme, PlanningQuestion, PlanningSummary, PlanningResponse, PlanningQuestionType, ArchivedTaskEntry, BatchStatusRequest, BatchStatusResponse, BatchStatusEntry, BatchStatusResult, ModelPreset } from "./types.js";
 export { TaskStore } from "./store.js";
 export { canTransition, getValidTransitions, resolveDependencyOrder } from "./board.js";
 export { 

packages/core/src/store.test.ts

@@ -121,6 +121,18 @@ describe("TaskStore", () => {
       expect(detail.breakIntoSubtasks).toBe(true);
     });
 
+    it("persists modelPresetId when provided during task creation", async () => {
+      const task = await store.createTask({
+        description: "Preset task",
+        modelPresetId: "budget",
+      });
+
+      expect(task.modelPresetId).toBe("budget");
+
+      const detail = await store.getTask(task.id);
+      expect(detail.modelPresetId).toBe("budget");
+    });
+
     it("leaves breakIntoSubtasks unset by default", async () => {
       const task = await store.createTask({
         description: "Regular task",

packages/core/src/store.ts

@@ -301,6 +301,7 @@ export class TaskStore extends EventEmitter<TaskStoreEvents> {
       column: input.column || "triage",
       dependencies: input.dependencies || [],
       breakIntoSubtasks: input.breakIntoSubtasks === true ? true : undefined,
+      modelPresetId: input.modelPresetId,
       modelProvider: input.modelProvider,
       modelId: input.modelId,
       validatorModelProvider: input.validatorModelProvider,
@@ -349,6 +350,7 @@ export class TaskStore extends EventEmitter<TaskStoreEvents> {
       title: sourceTask.title,
       description: `${sourceTask.description}\n\n(Duplicated from ${id})`,
       column: "triage",
+      modelPresetId: sourceTask.modelPresetId,
       dependencies: [], // Fresh task should have no dependencies
       steps: [], // Reset execution state
       currentStep: 0,
@@ -1053,6 +1055,7 @@ export class TaskStore extends EventEmitter<TaskStoreEvents> {
           updatedAt: task.updatedAt,
           columnMovedAt: task.columnMovedAt,
           archivedAt: task.columnMovedAt,
+          modelPresetId: task.modelPresetId,
           modelProvider: task.modelProvider,
           modelId: task.modelId,
           validatorModelProvider: task.validatorModelProvider,
@@ -1794,6 +1797,7 @@ export class TaskStore extends EventEmitter<TaskStoreEvents> {
       createdAt: entry.createdAt,
       updatedAt: new Date().toISOString(),
       columnMovedAt: entry.columnMovedAt,
+      modelPresetId: entry.modelPresetId,
       modelProvider: entry.modelProvider,
       modelId: entry.modelId,
       validatorModelProvider: entry.validatorModelProvider,

packages/core/src/types.ts

@@ -29,6 +29,15 @@ export type ColorTheme = (typeof COLOR_THEMES)[number];
 export type PrStatus = "open" | "closed" | "merged";
 export type MergeStrategy = "direct" | "pull-request";
 
+export interface ModelPreset {
+  id: string;
+  name: string;
+  executorProvider?: string;
+  executorModelId?: string;
+  validatorProvider?: string;
+  validatorModelId?: string;
+}
+
 export interface PrInfo {
   url: string;
   number: number;
@@ -166,6 +175,8 @@ export interface Task {
   log: TaskLogEntry[];
   size?: "S" | "M" | "L";
   reviewLevel?: number;
+  /** Model preset selected during task creation. Presets resolve to concrete model overrides at creation time. */
+  modelPresetId?: string;
   /** AI model provider override for the executor agent (e.g., "anthropic").
    *  Must be set together with `modelId`. When both model fields are undefined,
    *  the executor uses global settings defaults. */
@@ -205,6 +216,8 @@ export interface TaskCreateInput {
   column?: Column;
   dependencies?: string[];
   breakIntoSubtasks?: boolean;
+  /** Model preset selected during task creation. Presets resolve to concrete model overrides at creation time. */
+  modelPresetId?: string;
   /** AI model provider override for the executor agent (e.g., "anthropic").
    *  Must be set together with `modelId`. When both model fields are undefined,
    *  the executor uses global settings defaults. */
@@ -306,6 +319,12 @@ export interface Settings {
    *  Must be set together with `validatorProvider`. When both are undefined,
    *  falls back to `defaultProvider`/`defaultModelId`. */
   validatorModelId?: string;
+  /** Reusable model configuration presets for task creation. */
+  modelPresets?: ModelPreset[];
+  /** When true, task creation UIs automatically recommend/apply a preset based on task size. */
+  autoSelectModelPreset?: boolean;
+  /** Mapping of task sizes to preset IDs used for auto-selection during task creation. */
+  defaultPresetBySize?: { S?: string; M?: string; L?: string };
   /** Default thinking effort level for AI agent sessions.
    *  Controls how much reasoning effort the model uses — higher levels
    *  produce better results but cost more. When undefined, the engine
@@ -362,6 +381,9 @@ export const DEFAULT_SETTINGS: Settings = {
   planningModelId: undefined,
   validatorProvider: undefined,
   validatorModelId: undefined,
+  modelPresets: [],
+  autoSelectModelPreset: false,
+  defaultPresetBySize: {},
   defaultThinkingLevel: undefined,
   autoResolveConflicts: true,
   smartConflictResolution: true,
@@ -447,7 +469,8 @@ export interface ArchivedTaskEntry {
   columnMovedAt?: string;
   /** Timestamp when the task was archived to the log */
   archivedAt: string;
-  /** Optional: model override fields for executor and validator */
+  /** Optional: model preset and override fields for executor and validator */
+  modelPresetId?: string;
   modelProvider?: string;
   modelId?: string;
   validatorModelProvider?: string;