FN-5675: add mission branch strategy and planning breakdown controls

Add mission-level branch strategy support and expose planning breakdown controls across mission flows. - Extend mission/core data models and store logic to track and persist base-branch strategy metadata. - Update mission API routes and legacy adapters to read/write new mission branch strategy fields. - Enhance MissionManager and PlanningModeModal UX to configure branch strategy and planning breakdown behavior. - Add/adjust coverage across core, dashboard, and roadmap plugin tests for mission branch and planning flow behavior. - Add a changeset and mission docs updates for the new mission branch strategy behavior. Files changed: .changeset/fn-5675-mission-branch-strategy.md | 9 + docs/missions.md | 13 ++ packages/core/src/__tests__/db-migrate.test.ts | 12 +- .../src/__tests__/db-mission-base-branch.test.ts | 14 +- packages/core/src/__tests__/db.test.ts | 34 ++-- packages/core/src/__tests__/goals-schema.test.ts | 2 +- packages/core/src/__tests__/insight-store.test.ts | 10 +- packages/core/src/__tests__/mission-store.test.ts | 148 +++++++++++++- packages/core/src/__tests__/run-audit.test.ts | 2 +- packages/core/src/__tests__/secrets-schema.test.ts | 6 +- .../core/src/__tests__/store-merge-queue.test.ts | 2 +- packages/core/src/__tests__/task-documents.test.ts | 2 +- packages/core/src/db.ts | 9 +- packages/core/src/index.ts | 1 + packages/core/src/mission-store.ts | 64 ++++-- packages/core/src/mission-types.ts | 9 + packages/dashboard/app/api/legacy.ts | 23 ++- .../dashboard/app/components/MissionManager.tsx | 226 +++++++++++++++++++-- .../dashboard/app/components/PlanningModeModal.tsx | 9 +- .../components/__tests__/MissionManager.test.tsx | 100 +++++++++ .../PlanningModeModal.planning-flow.test.tsx | 91 +++++++++ packages/dashboard/app/components/mission-types.ts | 4 + .../dashboard/src/__tests__/mission-e2e.test.ts | 49 ++++- packages/dashboard/src/mission-routes.ts | 41 +++- .../src/store/__tests__/roadmap-store.test.ts | 4 +- 25 files changed, 808 insertions(+), 76 deletions(-) Fusion-Task-Id: FN-5675 Fusion-Task-Lineage: cfd13c13-9eff-4b82-90c3-88505d51bfb2
2026-05-29 15:25:47 -07:00
parent dae4c0ea5d
commit 0605d13ab5
25 changed files with 808 additions and 76 deletions
--- a/packages/core/src/tests/db-migrate.test.ts
+++ b/packages/core/src/tests/db-migrate.test.ts
@@ -715,7 +715,7 @@ describe("schema migration", () => {

    const row = db.prepare("SELECT deletedAt FROM tasks WHERE id = 'FN-legacy'").get() as { deletedAt: string | null };
    expect(row.deletedAt).toBeNull();
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    db.close();
  });
@@ -748,7 +748,7 @@ describe("schema migration", () => {
      { id: "WS-001", mode: "prompt", gateMode: "advisory" },
      { id: "WS-002", mode: "script", gateMode: "advisory" },
    ]);
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    db.close();
  });
@@ -798,7 +798,7 @@ describe("schema migration", () => {
      reviewerContextRetryCount: 0,
      reviewerFallbackRetryCount: 0,
    });
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    db.close();
  });
@@ -827,7 +827,7 @@ describe("schema migration", () => {

    const columns = db.prepare("PRAGMA table_info(milestones)").all() as Array<{ name: string }>;
    expect(columns.map((column) => column.name)).toContain("acceptanceCriteria");
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    db.close();
  });
@@ -868,7 +868,7 @@ describe("schema migration", () => {
    const missionColumns = db.prepare("PRAGMA table_info(missions)").all() as Array<{ name: string }>;
    expect(missionColumns.map((column) => column.name)).toContain("autoMerge");

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);
    db.close();
  });

@@ -902,7 +902,7 @@ describe("schema migration", () => {
      { id: "WS-002", mode: "script", enabled: 1, gateMode: "advisory" },
      { id: "WS-003", mode: "prompt", enabled: 0, gateMode: "advisory" },
    ]);
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    db.close();
  });
--- a/packages/core/src/tests/db-mission-base-branch.test.ts
+++ b/packages/core/src/tests/db-mission-base-branch.test.ts
@@ -10,7 +10,7 @@ function makeTmpDir(): string {
  return mkdtempSync(join(tmpdir(), "kb-db-mission-base-branch-"));
 }

-describe("mission baseBranch persistence", () => {
+describe("mission branch strategy persistence", () => {
  let tmpDir: string;
  let fusionDir: string;
  let db: Database;
@@ -29,21 +29,29 @@ describe("mission baseBranch persistence", () => {
    await rm(tmpDir, { recursive: true, force: true });
  });

-  it("creates, reads, and updates mission baseBranch", () => {
+  it("creates, reads, and updates mission baseBranch and branchStrategy", () => {
    const created = store.createMission({
      title: "Mission",
      baseBranch: "develop",
+      branchStrategy: { mode: "existing", branchName: "release/shared" },
    });

    expect(created.baseBranch).toBe("develop");
+    expect(created.branchStrategy).toEqual({ mode: "existing", branchName: "release/shared" });

    const fetched = store.getMission(created.id);
    expect(fetched?.baseBranch).toBe("develop");
+    expect(fetched?.branchStrategy).toEqual({ mode: "existing", branchName: "release/shared" });

-    const updated = store.updateMission(created.id, { baseBranch: "release/1.0" });
+    const updated = store.updateMission(created.id, {
+      baseBranch: "release/1.0",
+      branchStrategy: { mode: "auto-per-task" },
+    });
    expect(updated.baseBranch).toBe("release/1.0");
+    expect(updated.branchStrategy).toEqual({ mode: "auto-per-task" });

    const refetched = store.getMission(created.id);
    expect(refetched?.baseBranch).toBe("release/1.0");
+    expect(refetched?.branchStrategy).toEqual({ mode: "auto-per-task" });
  });
 });
--- a/packages/core/src/tests/db.test.ts
+++ b/packages/core/src/tests/db.test.ts
@@ -330,7 +330,7 @@ describe("Database", () => {
    });

    it("seeds schema version", () => {
-      expect(db.getSchemaVersion()).toBe(97);
+      expect(db.getSchemaVersion()).toBe(98);
    });

    it("includes tokenUsageCacheWriteTokens on freshly initialized tasks table", () => {
@@ -389,7 +389,7 @@ describe("Database", () => {

    it("is idempotent - calling init() twice does not fail", () => {
      expect(() => db.init()).not.toThrow();
-      expect(db.getSchemaVersion()).toBe(97);
+      expect(db.getSchemaVersion()).toBe(98);
    });
    it("does not overwrite existing config on re-init", () => {
      // Update the config
@@ -1459,7 +1459,7 @@ describe("schema migrations", () => {
    db.init();

    // Verify version bumped to 29 (includes v1→v2 through v26→v29)
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    // Verify new columns exist and existing data is intact
    const cols = db.prepare("PRAGMA table_info(tasks)").all() as Array<{ name: string }>;
@@ -1484,11 +1484,11 @@ describe("schema migrations", () => {
    const db = new Database(fusionDir);
    db.init();

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    // Re-init should not fail
    db.init();
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    db.close();
  });
@@ -1523,7 +1523,7 @@ describe("schema migrations", () => {

    db.init();

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    const cols = db.prepare("PRAGMA table_info(tasks)").all() as Array<{ name: string }>;
    expect(cols.map((col) => col.name)).toContain("priority");
@@ -1564,7 +1564,7 @@ describe("schema migrations", () => {

    db.init();

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    const cols = db.prepare("PRAGMA table_info(tasks)").all() as Array<{ name: string }>;
    const colNames = cols.map((col) => col.name);
@@ -1636,7 +1636,7 @@ describe("schema migrations", () => {

    db.init();

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    const cols = db.prepare("PRAGMA table_info(tasks)").all() as Array<{ name: string }>;
    const colNames = cols.map((col) => col.name);
@@ -1876,7 +1876,7 @@ describe("schema migrations", () => {

    db.init();

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    const cols = db.prepare("PRAGMA table_info(chat_messages)").all() as Array<{ name: string }>;
    expect(cols.map((col) => col.name)).toContain("attachments");
@@ -1950,7 +1950,7 @@ describe("schema migrations", () => {

    db.init();

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    const tables = db.prepare("SELECT name FROM sqlite_master WHERE type='table' AND name = 'agentRatings'").all() as Array<{ name: string }>;
    expect(tables).toEqual([{ name: "agentRatings" }]);
@@ -1974,7 +1974,7 @@ describe("schema migrations", () => {

    db.init();

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    const tables = db.prepare("SELECT name FROM sqlite_master WHERE type='table' AND name = 'mission_events'").all() as Array<{ name: string }>;
    expect(tables).toEqual([{ name: "mission_events" }]);
@@ -2078,7 +2078,7 @@ describe("schema migrations", () => {
    db.init();

    // Verify version bumped to 29
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    // Verify new columns exist and existing data is intact
    const cols = db.prepare("PRAGMA table_info(tasks)").all() as Array<{ name: string }>;
@@ -2297,7 +2297,7 @@ describe("schema migrations", () => {

    localDb.init();

-    expect(localDb.getSchemaVersion()).toBe(97);
+    expect(localDb.getSchemaVersion()).toBe(98);
    const columns = localDb.prepare("PRAGMA table_info(tasks)").all() as Array<{ name: string }>;
    expect(columns.map((column) => column.name)).toContain("tokenUsageCacheWriteTokens");

@@ -2608,7 +2608,7 @@ describe("createDatabase factory", () => {
    const db = createDatabase(fusionDir);
    db.init();

-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);
    expect(db.getLastModified()).toBeGreaterThan(0);

    db.close();
@@ -2762,7 +2762,7 @@ describe("migration v77 task token budget columns", () => {

      migrated = new Database(fusion);
      migrated.init();
-      expect(migrated.getSchemaVersion()).toBe(97);
+      expect(migrated.getSchemaVersion()).toBe(98);
      const rows = migrated.prepare("PRAGMA table_info(tasks)").all() as Array<{ name: string }>;
      const names = new Set(rows.map((row) => row.name));
      expect(names.has("tokenBudgetSoftAlertedAt")).toBe(true);
@@ -2808,7 +2808,7 @@ describe("migration v67 drops orphan project auth tables", () => {

      migrated = new Database(fusion);
      migrated.init();
-      expect(migrated.getSchemaVersion()).toBe(97);
+      expect(migrated.getSchemaVersion()).toBe(98);
      const tables = migrated
        .prepare("SELECT name FROM sqlite_master WHERE type='table' AND name LIKE 'project_auth_%'")
        .all() as Array<{ name: string }>;
@@ -2835,7 +2835,7 @@ describe("migration v67 drops orphan project auth tables", () => {

    try {
      fresh.init();
-      expect(fresh.getSchemaVersion()).toBe(97);
+      expect(fresh.getSchemaVersion()).toBe(98);
      const tables = fresh
        .prepare("SELECT name FROM sqlite_master WHERE type='table' AND name LIKE 'project_auth_%'")
        .all() as Array<{ name: string }>;
--- a/packages/core/src/tests/goals-schema.test.ts
+++ b/packages/core/src/tests/goals-schema.test.ts
@@ -91,6 +91,6 @@ describe("goals schema", () => {
  });

  it("reports schema version 92", () => {
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);
  });
 });
--- a/packages/core/src/tests/insight-store.test.ts
+++ b/packages/core/src/tests/insight-store.test.ts
@@ -1000,7 +1000,7 @@ describe("Migration: pre-33 DB upgrade", () => {
      // Step 1: Create a fresh database at v33 (runs all migrations up to 33)
      const db1 = createDatabase(legacyDir);
      db1.init();
-      expect(db1.getSchemaVersion()).toBe(97);
+      expect(db1.getSchemaVersion()).toBe(98);
      db1.close();

      // Step 2: Manually downgrade to version 32 and drop insight tables
@@ -1035,7 +1035,7 @@ describe("Migration: pre-33 DB upgrade", () => {
      expect(tableNamesBefore).not.toContain("project_insight_runs");
      // Now run init — this triggers the v32→v33 migration
      db3.init();
-      expect(db3.getSchemaVersion()).toBe(97);
+      expect(db3.getSchemaVersion()).toBe(98);

      // Step 4: Verify insight tables exist after migration
      const tablesAfter = db3.prepare(
@@ -1066,12 +1066,12 @@ describe("Migration: pre-33 DB upgrade", () => {
    try {
      const db1 = createDatabase(testDir);
      db1.init();
-      expect(db1.getSchemaVersion()).toBe(97);
+      expect(db1.getSchemaVersion()).toBe(98);
      db1.close();

      const db2 = createDatabase(testDir);
      expect(() => db2.init()).not.toThrow();
-      expect(db2.getSchemaVersion()).toBe(97);
+      expect(db2.getSchemaVersion()).toBe(98);
      db2.close();
    } finally {
      rmSync(testDir, { recursive: true, force: true });
@@ -1085,7 +1085,7 @@ describe("Migration: pre-33 DB upgrade", () => {
      // Step 1: Create a fresh DB and run migrations
      const db1 = createDatabase(compatDir);
      db1.init();
-      expect(db1.getSchemaVersion()).toBe(97);
+      expect(db1.getSchemaVersion()).toBe(98);

      // Step 2: Strip lifecycle and cancelledAt columns by recreating the
      // table without them. This simulates a DB that was created before the
--- a/packages/core/src/tests/mission-store.test.ts
+++ b/packages/core/src/tests/mission-store.test.ts
@@ -97,6 +97,35 @@ describe("MissionStore", () => {
      expect(list[2].id).toBe(m1.id);
    });

+    it("round-trips mission branchStrategy on create", () => {
+      const mission = store.createMission({
+        title: "Branch strategy",
+        branchStrategy: { mode: "custom-new", branchName: "feature/mission" },
+      });
+
+      const fetched = store.getMission(mission.id);
+      expect(fetched?.branchStrategy).toEqual({ mode: "custom-new", branchName: "feature/mission" });
+    });
+
+    it("updates mission branchStrategy", () => {
+      const mission = store.createMission({ title: "Original" });
+      const updated = store.updateMission(mission.id, {
+        branchStrategy: { mode: "auto-per-task" },
+      });
+
+      expect(updated.branchStrategy).toEqual({ mode: "auto-per-task" });
+      expect(store.getMission(mission.id)?.branchStrategy).toEqual({ mode: "auto-per-task" });
+    });
+
+    it("reads undefined branchStrategy for legacy and corrupt rows", () => {
+      const mission = store.createMission({ title: "Legacy row" });
+      db.prepare("UPDATE missions SET branchStrategy = NULL WHERE id = ?").run(mission.id);
+      expect(store.getMission(mission.id)?.branchStrategy).toBeUndefined();
+
+      db.prepare("UPDATE missions SET branchStrategy = ? WHERE id = ?").run("{not-json", mission.id);
+      expect(store.getMission(mission.id)?.branchStrategy).toBeUndefined();
+    });
+
    it("updates a mission", async () => {
      const mission = store.createMission({ title: "Original" });
      await new Promise((r) => setTimeout(r, 5)); // Ensure timestamp difference
@@ -1901,6 +1930,62 @@ describe("MissionStore", () => {
      expect(task?.baseBranch).toBe("release/1.0");
    });

+    it("uses mission branchStrategy auto-per-task when branch options are omitted", async () => {
+      const { TaskStore } = await import("../store.js");
+      const ts = new TaskStore(tmpDir, join(tmpDir, ".fusion-global-settings"), { inMemoryDb: true });
+      const msWithTs = ts.getMissionStore();
+
+      const mission = msWithTs.createMission({ title: "Mission", branchStrategy: { mode: "auto-per-task" } });
+      const milestone = msWithTs.addMilestone(mission.id, { title: "Milestone" });
+      const slice = msWithTs.addSlice(milestone.id, { title: "Slice" });
+      const feature = msWithTs.addFeature(slice.id, { title: "Original" });
+
+      const triaged = await msWithTs.triageFeature(feature.id);
+      const task = await ts.getTask(triaged.taskId!);
+
+      expect(task?.branchContext?.assignmentMode).toBe("per-task-derived");
+    });
+
+    it("uses mission branchStrategy existing branch when branch options are omitted", async () => {
+      const { TaskStore } = await import("../store.js");
+      const ts = new TaskStore(tmpDir, join(tmpDir, ".fusion-global-settings"), { inMemoryDb: true });
+      const msWithTs = ts.getMissionStore();
+
+      const mission = msWithTs.createMission({
+        title: "Mission",
+        branchStrategy: { mode: "existing", branchName: "release/shared" },
+      });
+      const milestone = msWithTs.addMilestone(mission.id, { title: "Milestone" });
+      const slice = msWithTs.addSlice(milestone.id, { title: "Slice" });
+      const feature = msWithTs.addFeature(slice.id, { title: "Original" });
+
+      const triaged = await msWithTs.triageFeature(feature.id);
+      const task = await ts.getTask(triaged.taskId!);
+
+      expect(task?.branch).toBe("release/shared");
+      expect(task?.branchContext?.assignmentMode).toBe("shared");
+    });
+
+    it("explicit branch options override mission branchStrategy defaults", async () => {
+      const { TaskStore } = await import("../store.js");
+      const ts = new TaskStore(tmpDir, join(tmpDir, ".fusion-global-settings"), { inMemoryDb: true });
+      const msWithTs = ts.getMissionStore();
+
+      const mission = msWithTs.createMission({ title: "Mission", branchStrategy: { mode: "auto-per-task" } });
+      const milestone = msWithTs.addMilestone(mission.id, { title: "Milestone" });
+      const slice = msWithTs.addSlice(milestone.id, { title: "Slice" });
+      const feature = msWithTs.addFeature(slice.id, { title: "Original" });
+
+      const triaged = await msWithTs.triageFeature(feature.id, undefined, undefined, {
+        branch: "hotfix/shared",
+        assignmentMode: "shared",
+      });
+      const task = await ts.getTask(triaged.taskId!);
+
+      expect(task?.branch).toBe("hotfix/shared");
+      expect(task?.branchContext?.assignmentMode).toBe("shared");
+    });
+
    it("uses provided title and description overrides", async () => {
      const { TaskStore } = await import("../store.js");
      const ts = new TaskStore(tmpDir, join(tmpDir, ".fusion-global-settings"), { inMemoryDb: true });
@@ -2080,6 +2165,52 @@ describe("MissionStore", () => {
      expect(task?.baseBranch).toBe("develop");
    });

+    it("triageSlice uses mission auto-per-task branchStrategy defaults", async () => {
+      const { TaskStore } = await import("../store.js");
+      const ts = new TaskStore(tmpDir, join(tmpDir, ".fusion-global-settings"), { inMemoryDb: true });
+      const msWithTs = ts.getMissionStore();
+
+      const mission = msWithTs.createMission({
+        title: "Mission",
+        branchStrategy: { mode: "auto-per-task" },
+      });
+      const milestone = msWithTs.addMilestone(mission.id, { title: "Milestone" });
+      const slice = msWithTs.addSlice(milestone.id, { title: "Slice" });
+      const f1 = msWithTs.addFeature(slice.id, { title: "Feature 1" });
+
+      const triaged = await msWithTs.triageSlice(slice.id);
+      const task = await ts.getTask(triaged[0].taskId!);
+
+      expect(triaged[0].id).toBe(f1.id);
+      expect(task?.branchContext?.assignmentMode).toBe("per-task-derived");
+    });
+
+    it("triageSlice respects explicit branch options over mission strategy defaults", async () => {
+      const { TaskStore } = await import("../store.js");
+      const ts = new TaskStore(tmpDir, join(tmpDir, ".fusion-global-settings"), { inMemoryDb: true });
+      const msWithTs = ts.getMissionStore();
+
+      const mission = msWithTs.createMission({
+        title: "Mission",
+        baseBranch: "develop",
+        branchStrategy: { mode: "auto-per-task" },
+      });
+      const milestone = msWithTs.addMilestone(mission.id, { title: "Milestone" });
+      const slice = msWithTs.addSlice(milestone.id, { title: "Slice" });
+      msWithTs.addFeature(slice.id, { title: "Feature 1" });
+
+      const triaged = await msWithTs.triageSlice(slice.id, {
+        branch: "feature/manual",
+        assignmentMode: "shared",
+        baseBranch: "release",
+      });
+      const task = await ts.getTask(triaged[0].taskId!);
+
+      expect(task?.branch).toBe("feature/manual");
+      expect(task?.baseBranch).toBe("release");
+      expect(task?.branchContext?.assignmentMode).toBe("shared");
+    });
+
    it("triageSlice does not inject baseBranch when mission has none", async () => {
      const { TaskStore } = await import("../store.js");
      const ts = new TaskStore(tmpDir, join(tmpDir, ".fusion-global-settings"), { inMemoryDb: true });
@@ -2159,6 +2290,21 @@ describe("MissionStore", () => {
      expect(task2!.missionId).toBe(mission.id);
    });

+    it("auto-triage uses mission branchStrategy defaults", async () => {
+      const { ts, ms } = await createStoreWithTaskStore();
+
+      const mission = ms.createMission({ title: "Mission", branchStrategy: { mode: "auto-per-task" } });
+      ms.updateMission(mission.id, { autoAdvance: true });
+      const milestone = ms.addMilestone(mission.id, { title: "Milestone" });
+      const slice = ms.addSlice(milestone.id, { title: "Slice" });
+      const feature = ms.addFeature(slice.id, { title: "Feature 1" });
+
+      await ms.activateSlice(slice.id);
+
+      const task = await ts.getTask(ms.getFeature(feature.id)!.taskId!);
+      expect(task?.branchContext?.assignmentMode).toBe("per-task-derived");
+    });
+
    it("does not triage features when autoAdvance is false", async () => {
      const { ms } = await createStoreWithTaskStore();

@@ -3036,7 +3182,7 @@ describe("MissionStore", () => {

  describe("Loop State & Validator Run Schema (v31)", () => {
    it("schema version is 40 after migration", () => {
-      expect(db.getSchemaVersion()).toBe(97);
+      expect(db.getSchemaVersion()).toBe(98);
    });

    it("mission_features table has loop state columns", () => {
--- a/packages/core/src/tests/run-audit.test.ts
+++ b/packages/core/src/tests/run-audit.test.ts
@@ -584,7 +584,7 @@ describe("Run Audit", () => {
    });

    it("schema version is bumped to 40", () => {
-      expect(db.getSchemaVersion()).toBe(97);
+      expect(db.getSchemaVersion()).toBe(98);
    });
  });
 });
--- a/packages/core/src/tests/secrets-schema.test.ts
+++ b/packages/core/src/tests/secrets-schema.test.ts
@@ -42,7 +42,7 @@ describe("secrets schema migrations", () => {
      const version = db
        .prepare("SELECT value FROM __meta WHERE key = 'schemaVersion'")
        .get() as { value: string };
-      expect(version.value).toBe("97");
+      expect(version.value).toBe("98");
    } finally {
      db.close();
      rmSync(dir, { recursive: true, force: true });
@@ -105,7 +105,7 @@ describe("secrets schema migrations", () => {
      const version = db
        .prepare("SELECT value FROM __meta WHERE key = 'schemaVersion'")
        .get() as { value: string };
-      expect(version.value).toBe("97");
+      expect(version.value).toBe("98");
    } finally {
      db.close();
      rmSync(dir, { recursive: true, force: true });
@@ -155,7 +155,7 @@ describe("secrets schema migrations", () => {
        .prepare("SELECT value FROM __meta WHERE key = 'schemaVersion'")
        .get() as { value: string };

-      expect(projectVersion.value).toBe("97");
+      expect(projectVersion.value).toBe("98");
      expect(centralVersion.value).toBe("13");
    } finally {
      projectDb.close();
--- a/packages/core/src/tests/store-merge-queue.test.ts
+++ b/packages/core/src/tests/store-merge-queue.test.ts
@@ -60,7 +60,7 @@ describe("TaskStore merge queue", () => {
      expect.arrayContaining(["idx_mergeQueue_lease_ready", "idx_mergeQueue_leaseExpiresAt"]),
    );

-    expect(store.getDatabase().getSchemaVersion()).toBe(97);
+    expect(store.getDatabase().getSchemaVersion()).toBe(98);
  });

  it("migrates a legacy v88 database and preserves task rows", async () => {
--- a/packages/core/src/tests/task-documents.test.ts
+++ b/packages/core/src/tests/task-documents.test.ts
@@ -51,7 +51,7 @@ describe("TaskStore task documents", () => {

    expect(tableNames.has("task_documents")).toBe(true);
    expect(tableNames.has("task_document_revisions")).toBe(true);
-    expect(db.getSchemaVersion()).toBe(97);
+    expect(db.getSchemaVersion()).toBe(98);

    const index = db
      .prepare(
--- a/packages/core/src/db.ts
+++ b/packages/core/src/db.ts
@@ -149,7 +149,7 @@ export function probeFts5(db: DatabaseSync): boolean {

 // ── Schema Definition ────────────────────────────────────────────────

-const SCHEMA_VERSION = 97;
+const SCHEMA_VERSION = 98;

 function normalizeTaskComments(
  steeringComments: SteeringComment[] | undefined,
@@ -758,6 +758,7 @@ CREATE TABLE IF NOT EXISTS missions (
  status TEXT NOT NULL,
  interviewState TEXT NOT NULL,
  baseBranch TEXT,
+  branchStrategy TEXT,
  autoAdvance INTEGER DEFAULT 0,
  autoMerge INTEGER,
  createdAt TEXT NOT NULL,
@@ -3719,6 +3720,12 @@ export class Database {
      });
    }

+    if (version < 98) {
+      this.applyMigration(98, () => {
+        this.addColumnIfMissing("missions", "branchStrategy", "TEXT");
+      });
+    }
+
  }

  /**
--- a/packages/core/src/index.ts
+++ b/packages/core/src/index.ts
@@ -675,6 +675,7 @@ export type {
  MissionEventType,
  AutopilotStatus,
  Mission,
+  MissionBranchStrategy,
  Milestone,
  Slice,
  MissionFeature,
--- a/packages/core/src/mission-store.ts
+++ b/packages/core/src/mission-store.ts
@@ -16,6 +16,7 @@ import type { Database } from "./db.js";
 import { fromJson, toJson, toJsonNullable } from "./db.js";
 import type {
  Mission,
+  MissionBranchStrategy,
  Milestone,
  Slice,
  MissionFeature,
@@ -63,6 +64,22 @@ import { reconcileDeterministicDuplicate, runDeterministicDuplicateGuard } from
 */
 const DEFAULT_IMPLEMENTATION_RETRY_BUDGET = 3;

+function missionBranchStrategyDefaults(strategy?: MissionBranchStrategy): {
+  branch?: string;
+  assignmentMode: "shared" | "per-task-derived";
+} {
+  if (!strategy) {
+    return { assignmentMode: "shared" };
+  }
+  if (strategy.mode === "auto-per-task") {
+    return { assignmentMode: "per-task-derived" };
+  }
+  if ((strategy.mode === "existing" || strategy.mode === "custom-new") && strategy.branchName?.trim()) {
+    return { branch: strategy.branchName.trim(), assignmentMode: "shared" };
+  }
+  return { assignmentMode: "shared" };
+}
+
 export function deriveMilestoneAcceptanceCriteriaFromFeatures(features: MissionFeature[]): string | undefined {
  const lines = features
    .map((feature) => {
@@ -189,6 +206,7 @@ interface MissionRow {
  status: string;
  interviewState: string;
  baseBranch: string | null;
+  branchStrategy: string | null;
  autoMerge: number | null;
  autoAdvance: number;
  autopilotEnabled: number;
@@ -356,6 +374,15 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
   * Convert a database row to a Mission object.
   */
  private rowToMission(row: MissionRow): Mission {
+    let branchStrategy: MissionBranchStrategy | undefined;
+    if (row.branchStrategy) {
+      try {
+        branchStrategy = JSON.parse(row.branchStrategy) as MissionBranchStrategy;
+      } catch {
+        branchStrategy = undefined;
+      }
+    }
+
    return {
      id: row.id,
      title: row.title,
@@ -363,6 +390,7 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
      status: row.status as MissionStatus,
      interviewState: row.interviewState as InterviewState,
      baseBranch: row.baseBranch || undefined,
+      branchStrategy,
      autoMerge: row.autoMerge === null ? undefined : Boolean(row.autoMerge),
      autoAdvance: Boolean(row.autoAdvance),
      autopilotEnabled: Boolean(row.autopilotEnabled),
@@ -555,6 +583,7 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
      status: "planning",
      interviewState: "not_started",
      baseBranch: input.baseBranch,
+      branchStrategy: input.branchStrategy,
      autoMerge: input.autoMerge,
      autoAdvance: false,
      autopilotEnabled: input.autopilotEnabled ?? false,
@@ -564,8 +593,8 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
    };

    this.db.prepare(`
-      INSERT INTO missions (id, title, description, status, interviewState, baseBranch, autoMerge, autoAdvance, autopilotEnabled, autopilotState, createdAt, updatedAt)
-      VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+      INSERT INTO missions (id, title, description, status, interviewState, baseBranch, branchStrategy, autoMerge, autoAdvance, autopilotEnabled, autopilotState, createdAt, updatedAt)
+      VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
    `).run(
      mission.id,
      mission.title,
@@ -573,6 +602,7 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
      mission.status,
      mission.interviewState,
      mission.baseBranch ?? null,
+      mission.branchStrategy ? JSON.stringify(mission.branchStrategy) : null,
      mission.autoMerge === undefined ? null : (mission.autoMerge ? 1 : 0),
      mission.autoAdvance ? 1 : 0,
      mission.autopilotEnabled ? 1 : 0,
@@ -1126,6 +1156,7 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
        status = ?,
        interviewState = ?,
        baseBranch = ?,
+        branchStrategy = ?,
        autoMerge = ?,
        autoAdvance = ?,
        autopilotEnabled = ?,
@@ -1139,6 +1170,7 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
      updated.status,
      updated.interviewState,
      updated.baseBranch ?? null,
+      updated.branchStrategy ? JSON.stringify(updated.branchStrategy) : null,
      updated.autoMerge === undefined ? null : (updated.autoMerge ? 1 : 0),
      updated.autoAdvance ? 1 : 0,
      updated.autopilotEnabled ? 1 : 0,
@@ -3305,7 +3337,10 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
    const milestone = slice ? this.getMilestone(slice.milestoneId) : undefined;
    const missionId = milestone?.missionId;
    const mission = missionId ? this.getMission(missionId) : undefined;
+    const strategyDefaults = missionBranchStrategyDefaults(mission?.branchStrategy);
    const resolvedBaseBranch = branchOptions?.baseBranch ?? mission?.baseBranch;
+    const resolvedBranch = branchOptions?.branch ?? strategyDefaults.branch;
+    const resolvedAssignmentMode = branchOptions?.assignmentMode ?? strategyDefaults.assignmentMode;

    const lockScope = missionId ? `mission:${missionId}` : `mission-store:${this.taskStore.getRootDir()}`;
    const guard = await runDeterministicDuplicateGuard(this.taskStore, {
@@ -3321,14 +3356,14 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
        const createdTask = await this.taskStore.createTask({
          title: taskTitle || feature.title,
          description,
-          branch: branchOptions?.branch,
+          branch: resolvedBranch,
          baseBranch: resolvedBaseBranch,
          ...(missionId
            ? {
                branchContext: {
                  groupId: `mission:${missionId}`,
                  source: "mission" as const,
-                  assignmentMode: branchOptions?.assignmentMode ?? "shared",
+                  assignmentMode: resolvedAssignmentMode,
                  inheritedBaseBranch: resolvedBaseBranch,
                },
              }
@@ -3389,17 +3424,21 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
    const definedFeatures = features.filter((f) => f.status === "defined");
    const milestone = this.getMilestone(slice.milestoneId);
    const mission = milestone ? this.getMission(milestone.missionId) : undefined;
+    const strategyDefaults = missionBranchStrategyDefaults(mission?.branchStrategy);
    const resolvedBaseBranch = branchOptions?.baseBranch ?? mission?.baseBranch;
+    const resolvedAssignmentMode = branchOptions?.assignmentMode ?? strategyDefaults.assignmentMode;
+    const resolvedBranch = branchOptions?.branch ?? strategyDefaults.branch;

    const triaged: MissionFeature[] = [];
    for (const feature of definedFeatures) {
-      const branch = branchOptions?.assignmentMode === "per-task-derived"
-        ? (branchOptions?.branch ? `${branchOptions.branch}/${feature.id.toLowerCase()}` : undefined)
-        : branchOptions?.branch;
+      const strategyBranch = resolvedAssignmentMode === "per-task-derived"
+        ? (resolvedBranch ? `${resolvedBranch}/${feature.id.toLowerCase()}` : undefined)
+        : resolvedBranch;
      const updated = await this.triageFeature(feature.id, undefined, undefined, {
-        ...branchOptions,
-        branch,
+        branch: strategyBranch,
        baseBranch: resolvedBaseBranch,
+        assignmentMode: resolvedAssignmentMode,
+        ...branchOptions,
      });
      triaged.push(updated);
    }
@@ -3589,13 +3628,14 @@ export class MissionStore extends EventEmitter<MissionStoreEvents> {
    let applied = 0;

    for (const mission of snapshot.payload.missions) {
-      this.db.prepare(`INSERT INTO missions (id, title, description, status, interviewState, autoMerge, autoAdvance, autopilotEnabled, autopilotState, lastAutopilotActivityAt, createdAt, updatedAt)
-        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+      this.db.prepare(`INSERT INTO missions (id, title, description, status, interviewState, baseBranch, branchStrategy, autoMerge, autoAdvance, autopilotEnabled, autopilotState, lastAutopilotActivityAt, createdAt, updatedAt)
+        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
        ON CONFLICT(id) DO UPDATE SET
          title=excluded.title, description=excluded.description, status=excluded.status, interviewState=excluded.interviewState,
-          autoMerge=excluded.autoMerge, autoAdvance=excluded.autoAdvance, autopilotEnabled=excluded.autopilotEnabled, autopilotState=excluded.autopilotState,
+          baseBranch=excluded.baseBranch, branchStrategy=excluded.branchStrategy, autoMerge=excluded.autoMerge, autoAdvance=excluded.autoAdvance, autopilotEnabled=excluded.autopilotEnabled, autopilotState=excluded.autopilotState,
          lastAutopilotActivityAt=excluded.lastAutopilotActivityAt, updatedAt=excluded.updatedAt`).run(
        mission.id, mission.title, mission.description ?? null, mission.status, mission.interviewState,
+        mission.baseBranch ?? null, mission.branchStrategy ? JSON.stringify(mission.branchStrategy) : null,
        mission.autoMerge === undefined ? null : (mission.autoMerge ? 1 : 0), mission.autoAdvance ? 1 : 0,
        mission.autopilotEnabled ? 1 : 0, mission.autopilotState, mission.lastAutopilotActivityAt ?? null, mission.createdAt, mission.updatedAt,
      );
--- a/packages/core/src/mission-types.ts
+++ b/packages/core/src/mission-types.ts
@@ -113,6 +113,11 @@ export interface MissionHealth {
 * A Mission represents a high-level objective or project.
 * Missions contain milestones that break down the work into phases.
 */
+export type MissionBranchStrategy = {
+  mode: "project-default" | "existing" | "custom-new" | "auto-per-task";
+  branchName?: string;
+};
+
 export interface Mission {
  /** Unique identifier (e.g., "M-LZ7DN0-A2B5") */
  id: string;
@@ -124,6 +129,8 @@ export interface Mission {
  status: MissionStatus;
  /** Optional integration base branch inherited by triaged feature tasks */
  baseBranch?: string;
+  /** Mission triage branch strategy: auto-per-task => assignmentMode "per-task-derived"; existing/custom-new => shared branchName; project-default/absent => shared default behavior. */
+  branchStrategy?: MissionBranchStrategy;
  /** State of the AI specification interview process */
  interviewState: InterviewState;
  /**
@@ -375,6 +382,8 @@ export interface MissionCreateInput {
  description?: string;
  /** Optional integration base branch for tasks created from this mission */
  baseBranch?: string;
+  /** Optional branch strategy applied as the default for mission triage operations. */
+  branchStrategy?: MissionBranchStrategy;
  /** Optional mission-level auto-merge override for linked task branches. */
  autoMerge?: boolean;
 }