diff --git a/src/resources/extensions/gsd/auto.ts b/src/resources/extensions/gsd/auto.ts
index ad38c8a27..d29ba0b48 100644
--- a/src/resources/extensions/gsd/auto.ts
+++ b/src/resources/extensions/gsd/auto.ts
@@ -2102,7 +2102,7 @@ async function dispatchNextUnit(
   // Lightweight check for critical issues that would cause the next unit
   // to fail or corrupt state. Auto-heals what it can, blocks on the rest.
   try {
-    const healthGate = preDispatchHealthGate(basePath);
+    const healthGate = await preDispatchHealthGate(basePath);
     if (healthGate.fixesApplied.length > 0) {
       ctx.ui.notify(`Pre-dispatch: ${healthGate.fixesApplied.join(", ")}`, "info");
     }
diff --git a/src/resources/extensions/gsd/doctor-proactive.ts b/src/resources/extensions/gsd/doctor-proactive.ts
index 77fbf5a26..810cd46aa 100644
--- a/src/resources/extensions/gsd/doctor-proactive.ts
+++ b/src/resources/extensions/gsd/doctor-proactive.ts
@@ -19,6 +19,7 @@ import { join } from "node:path";
 import { gsdRoot, resolveGsdRootFile } from "./paths.js";
 import { readCrashLock, isLockProcessAlive, clearLock } from "./crash-recovery.js";
 import { abortAndReset } from "./git-self-heal.js";
+import { rebuildState } from "./doctor.js";
 
 // ── Health Score Tracking ──────────────────────────────────────────────────
 
@@ -131,7 +132,7 @@ export interface PreDispatchHealthResult {
  *
  * Returns { proceed: true } if dispatch should continue.
  */
-export function preDispatchHealthGate(basePath: string): PreDispatchHealthResult {
+export async function preDispatchHealthGate(basePath: string): Promise<PreDispatchHealthResult> {
   const issues: string[] = [];
   const fixesApplied: string[] = [];
 
@@ -172,17 +173,17 @@ export function preDispatchHealthGate(basePath: string): PreDispatchHealthResult
   }
 
   // ── STATE.md existence check ──
-  // If STATE.md is missing, deriveState will still work but the LLM
-  // may get confused. Rebuild it silently.
+  // If STATE.md is missing, rebuild it now so the next unit has accurate
+  // context. Non-blocking — if the rebuild throws, dispatch continues anyway.
   try {
     const stateFile = resolveGsdRootFile(basePath, "STATE");
     const milestonesDir = join(gsdRoot(basePath), "milestones");
     if (existsSync(milestonesDir) && !existsSync(stateFile)) {
-      issues.push("STATE.md missing — will rebuild after this unit");
-      // Don't block dispatch — rebuilding happens in post-hook
+      await rebuildState(basePath);
+      fixesApplied.push("rebuilt missing STATE.md before dispatch");
     }
   } catch {
-    // Non-fatal
+    // Non-fatal — dispatch continues without STATE.md if rebuild fails
   }
 
   // If we had critical issues that couldn't be auto-healed, block dispatch
diff --git a/src/resources/extensions/gsd/tests/doctor-proactive.test.ts b/src/resources/extensions/gsd/tests/doctor-proactive.test.ts
index b532edc5f..4e4d86bb8 100644
--- a/src/resources/extensions/gsd/tests/doctor-proactive.test.ts
+++ b/src/resources/extensions/gsd/tests/doctor-proactive.test.ts
@@ -188,7 +188,7 @@ async function main(): Promise<void> {
       cleanups.push(dir);
       mkdirSync(join(dir, ".gsd"), { recursive: true });
 
-      const result = preDispatchHealthGate(dir);
+      const result = await preDispatchHealthGate(dir);
       assertTrue(result.proceed, "gate passes on clean state");
       assertEq(result.issues.length, 0, "no issues on clean state");
     }
@@ -206,7 +206,7 @@ async function main(): Promise<void> {
         unitStartedAt: "2026-03-10T00:01:00Z", completedUnits: 3,
       }));
 
-      const result = preDispatchHealthGate(dir);
+      const result = await preDispatchHealthGate(dir);
       assertTrue(result.proceed, "gate passes after auto-clearing stale lock");
       assertTrue(result.fixesApplied.some(f => f.includes("cleared stale auto.lock")), "reports lock cleared");
       assertTrue(!existsSync(join(dir, ".gsd", "auto.lock")), "lock file removed");
@@ -222,7 +222,7 @@ async function main(): Promise<void> {
       const headHash = run("git rev-parse HEAD", dir);
       writeFileSync(join(dir, ".git", "MERGE_HEAD"), headHash + "\n");
 
-      const result = preDispatchHealthGate(dir);
+      const result = await preDispatchHealthGate(dir);
       assertTrue(result.proceed, "gate passes after auto-healing merge state");
       assertTrue(result.fixesApplied.some(f => f.includes("cleaned merge state")), "reports merge state cleaned");
       assertTrue(!existsSync(join(dir, ".git", "MERGE_HEAD")), "MERGE_HEAD removed");
@@ -231,6 +231,26 @@ async function main(): Promise<void> {
       console.log("  (skipped on Windows)");
     }
 
+    console.log("\n=== health gate: STATE.md missing — auto-healed ===");
+    {
+      const dir = realpathSync(mkdtempSync(join(tmpdir(), "doc-proactive-")));
+      cleanups.push(dir);
+      // Minimal .gsd structure: milestones dir exists but no STATE.md
+      mkdirSync(join(dir, ".gsd", "milestones"), { recursive: true });
+
+      const stateFile = join(dir, ".gsd", "STATE.md");
+      assertTrue(!existsSync(stateFile), "STATE.md does not exist before gate");
+
+      const result = await preDispatchHealthGate(dir);
+      assertTrue(result.proceed, "gate passes after rebuilding STATE.md");
+      assertTrue(
+        result.fixesApplied.some(f => f.includes("rebuilt missing STATE.md")),
+        "reports STATE.md rebuilt",
+      );
+      assertTrue(existsSync(stateFile), "STATE.md created by auto-heal");
+      assertTrue(result.issues.length === 0, "no blocking issues after heal");
+    }
+
   } finally {
     resetProactiveHealing();
     for (const dir of cleanups) {
diff --git a/src/tests/app-smoke.test.ts b/src/tests/app-smoke.test.ts
index 6e36ae2b2..dceb25fc2 100644
--- a/src/tests/app-smoke.test.ts
+++ b/src/tests/app-smoke.test.ts
@@ -13,7 +13,7 @@
 import test from "node:test";
 import assert from "node:assert/strict";
 import { execSync } from "node:child_process";
-import { existsSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
+import { existsSync, mkdirSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
 import { delimiter, join } from "node:path";
 import { tmpdir } from "node:os";
 import { fileURLToPath } from "node:url";
@@ -235,3 +235,159 @@ test("loadStoredEnvKeys does not overwrite existing env vars", async () => {
     rmSync(tmp, { recursive: true, force: true });
   }
 });
+
+// ═══════════════════════════════════════════════════════════════════════════
+// 6. State derivation — Gap 2
+// ═══════════════════════════════════════════════════════════════════════════
+
+test("deriveState returns pre-planning phase for empty .gsd/ directory", async () => {
+  const { deriveState } = await import("../resources/extensions/gsd/state.ts");
+  const tmp = mkdtempSync(join(tmpdir(), "gsd-state-smoke-"));
+
+  // Create minimal .gsd/ structure with no milestones
+  mkdirSync(join(tmp, ".gsd"), { recursive: true });
+
+  try {
+    const state = await deriveState(tmp);
+
+    assert.equal(state.phase, "pre-planning",
+      `expected pre-planning phase for empty .gsd/, got: ${state.phase}`);
+    assert.equal(state.activeMilestone, null, "no active milestone");
+    assert.equal(state.activeSlice, null, "no active slice");
+    assert.equal(state.activeTask, null, "no active task");
+    assert.ok(Array.isArray(state.blockers), "blockers is an array");
+    assert.ok(Array.isArray(state.registry), "registry is an array");
+    assert.equal(state.registry.length, 0, "empty registry");
+    assert.ok(typeof state.nextAction === "string", "nextAction is a string");
+    assert.ok(state.nextAction.length > 0, "nextAction is non-empty");
+  } finally {
+    rmSync(tmp, { recursive: true, force: true });
+  }
+});
+
+test("deriveState returns pre-planning phase when no .gsd/ directory exists", async () => {
+  const { deriveState } = await import("../resources/extensions/gsd/state.ts");
+  // Use a temp dir with no .gsd/ subdirectory at all
+  const tmp = mkdtempSync(join(tmpdir(), "gsd-state-nogsd-"));
+
+  try {
+    // Should not throw — missing .gsd/ is a valid "no project" state
+    const state = await deriveState(tmp);
+
+    assert.equal(state.phase, "pre-planning",
+      `expected pre-planning phase when .gsd/ absent, got: ${state.phase}`);
+    assert.equal(state.activeMilestone, null, "no active milestone");
+  } finally {
+    rmSync(tmp, { recursive: true, force: true });
+  }
+});
+
+test("deriveState shape is structurally complete", async () => {
+  const { deriveState } = await import("../resources/extensions/gsd/state.ts");
+  const tmp = mkdtempSync(join(tmpdir(), "gsd-state-shape-"));
+  mkdirSync(join(tmp, ".gsd"), { recursive: true });
+
+  try {
+    const state = await deriveState(tmp);
+
+    // All required fields present
+    const requiredFields = [
+      "phase", "activeMilestone", "activeSlice", "activeTask",
+      "recentDecisions", "blockers", "nextAction", "registry",
+    ] as const;
+    for (const field of requiredFields) {
+      assert.ok(field in state, `state.${field} should be present`);
+    }
+
+    // phase is a known string value
+    const validPhases = [
+      "pre-planning", "needs-discussion", "researching", "planning",
+      "executing", "summarizing", "replanning-slice", "validating-milestone",
+      "completing-milestone", "complete", "blocked",
+    ];
+    assert.ok(validPhases.includes(state.phase),
+      `state.phase '${state.phase}' should be a known phase`);
+  } finally {
+    rmSync(tmp, { recursive: true, force: true });
+  }
+});
+
+// ═══════════════════════════════════════════════════════════════════════════
+// 7. Doctor health checks — Gap 3
+// ═══════════════════════════════════════════════════════════════════════════
+
+test("runGSDDoctor completes without throwing on empty .gsd/ directory", async () => {
+  const { runGSDDoctor } = await import("../resources/extensions/gsd/doctor.ts");
+  const tmp = mkdtempSync(join(tmpdir(), "gsd-doctor-smoke-"));
+  mkdirSync(join(tmp, ".gsd"), { recursive: true });
+
+  try {
+    // audit-only mode (fix: false) — should never throw
+    const report = await runGSDDoctor(tmp, { fix: false });
+
+    // Structural assertions on the DoctorReport
+    assert.ok(typeof report === "object" && report !== null, "report is an object");
+    assert.ok("ok" in report, "report has ok field");
+    assert.ok("issues" in report, "report has issues field");
+    assert.ok("fixesApplied" in report, "report has fixesApplied field");
+    assert.ok("basePath" in report, "report has basePath field");
+    assert.ok(Array.isArray(report.issues), "report.issues is an array");
+    assert.ok(Array.isArray(report.fixesApplied), "report.fixesApplied is an array");
+    assert.equal(typeof report.ok, "boolean", "report.ok is a boolean");
+    assert.equal(report.fixesApplied.length, 0, "no fixes applied in audit mode");
+  } finally {
+    rmSync(tmp, { recursive: true, force: true });
+  }
+});
+
+test("runGSDDoctor issue objects have required fields", async () => {
+  const { runGSDDoctor } = await import("../resources/extensions/gsd/doctor.ts");
+  const tmp = mkdtempSync(join(tmpdir(), "gsd-doctor-fields-"));
+  mkdirSync(join(tmp, ".gsd"), { recursive: true });
+
+  // Create a milestone dir with no ROADMAP.md to force a missing_roadmap issue
+  const mDir = join(tmp, ".gsd", "milestones", "M001");
+  mkdirSync(mDir, { recursive: true });
+  writeFileSync(join(mDir, "M001-CONTEXT.md"), "# Context\n");
+
+  try {
+    const report = await runGSDDoctor(tmp, { fix: false });
+
+    // Should find at least one issue (missing roadmap for M001)
+    assert.ok(report.issues.length > 0, "expected at least one issue for milestone missing ROADMAP.md");
+
+    // Verify structure of each issue
+    for (const issue of report.issues) {
+      assert.ok(typeof issue.severity === "string", "issue.severity is a string");
+      assert.ok(["info", "warning", "error"].includes(issue.severity),
+        `issue.severity '${issue.severity}' should be info|warning|error`);
+      assert.ok(typeof issue.code === "string", "issue.code is a string");
+      assert.ok(typeof issue.message === "string", "issue.message is a string");
+      assert.ok(issue.message.length > 0, "issue.message is non-empty");
+      assert.ok(typeof issue.fixable === "boolean", "issue.fixable is a boolean");
+    }
+  } finally {
+    rmSync(tmp, { recursive: true, force: true });
+  }
+});
+
+test("runGSDDoctor with fix:false never modifies the filesystem", async () => {
+  const { runGSDDoctor } = await import("../resources/extensions/gsd/doctor.ts");
+  const tmp = mkdtempSync(join(tmpdir(), "gsd-doctor-readonly-"));
+  const gsdDir = join(tmp, ".gsd");
+  mkdirSync(gsdDir, { recursive: true });
+
+  // Write a sentinel file — doctor must not delete or modify it
+  const sentinelPath = join(gsdDir, "SENTINEL.md");
+  writeFileSync(sentinelPath, "# sentinel\n");
+
+  try {
+    await runGSDDoctor(tmp, { fix: false });
+
+    assert.ok(existsSync(sentinelPath), "sentinel file still exists after audit-only run");
+    const content = readFileSync(sentinelPath, "utf-8");
+    assert.equal(content, "# sentinel\n", "sentinel file content unchanged");
+  } finally {
+    rmSync(tmp, { recursive: true, force: true });
+  }
+});