diff --git a/src/runtime/AGENTS.md b/src/runtime/AGENTS.md
index a28e8ec..7c47980 100644
--- a/src/runtime/AGENTS.md
+++ b/src/runtime/AGENTS.md
@@ -25,7 +25,7 @@ Runtime domain for planner stages, model-facing status, tool wrappers, timers, r
 
 ### Do Not Touch Unless
 - Do not change lifecycle transitions without updating `state-machine.ts`, `state-transition.ts`, `workflow-tools.ts`, tests, and instructions.
-- Do not add a new planner tool without updating guard policy, tool visibility expectations, status/instructions, and tests.
+- Do not add or re-scope a planner tool without updating BOTH allowlists that gate it: the guard policy (`guard/tool-policy.ts` `STEP_ALLOWED_TOOLS`) AND the stage behavior (`stage-behavior.ts` `expectedTools`). Both gates must pass for a tool to be usable at a step; if the guard allows a tool the behavior gate omits, the model is blocked at runtime (a deadlock when no fallback exists). The invariant is enforced by `tool-gating-invariant.test.ts`. Also update tool visibility expectations, status/instructions, and tests.
 
 ### Domain Details
 - `status.ts` is the primary prompt surface for local models; it reads `PlanStateRecord` from the orchestrator and formats step rules, contract summaries, and guidance lines.
diff --git a/src/runtime/artifact-tools.gating.test.ts b/src/runtime/artifact-tools.gating.test.ts
new file mode 100644
index 0000000..b64b1cc
--- /dev/null
+++ b/src/runtime/artifact-tools.gating.test.ts
@@ -0,0 +1,72 @@
+import { describe, expect, it } from "vitest";
+import {
+	getAllowedPlannerWrapperTools,
+	type PlannerWrapperTool,
+} from "../guard/tool-policy";
+import type { PlannerStage, PlannerStep } from "../storage/schema";
+import {
+	checkPlannerStageBehaviorWrapperTool,
+	getPlannerStageStepBehavior,
+} from "./stage-behavior";
+
+// Each structured fill-tool must be permitted by BOTH allowlists at every step
+// where it is used: the guard policy (STEP_ALLOWED_TOOLS) and the stage-behavior
+// expectedTools gate. Missing either one deadlocks the model — and for tdd.md,
+// where built-in edit/write is blocked, there is no fallback at all.
+const FILL_TOOL_STEPS: Array<{
+	stage: PlannerStage;
+	step: PlannerStep;
+	tool: PlannerWrapperTool;
+}> = [
+	{
+		stage: "discovery",
+		step: "scan_project_structure",
+		tool: "planner_discovery_submit",
+	},
+	{ stage: "planning", step: "draft_plan", tool: "planner_plan_submit" },
+	{ stage: "execution", step: "write_tdd_plan", tool: "planner_tdd_submit" },
+	{ stage: "execution", step: "write_tests", tool: "planner_tdd_submit" },
+	{ stage: "execution", step: "run_failing_tests", tool: "planner_tdd_submit" },
+	{ stage: "execution", step: "implement_task", tool: "planner_tdd_submit" },
+	{ stage: "execution", step: "contract_check", tool: "planner_tdd_submit" },
+	{ stage: "execution", step: "refactor_task", tool: "planner_tdd_submit" },
+	{ stage: "execution", step: "run_final_tests", tool: "planner_tdd_submit" },
+	{
+		stage: "execution",
+		step: "merge_task_to_plan",
+		tool: "planner_tdd_submit",
+	},
+	{
+		stage: "finalize",
+		step: "write_final_summary",
+		tool: "planner_summary_submit",
+	},
+	{ stage: "done", step: "handle_change_request", tool: "planner_plan_submit" },
+	{
+		stage: "done",
+		step: "handle_change_request",
+		tool: "planner_discovery_submit",
+	},
+];
+
+describe("artifact fill-tool gating", () => {
+	for (const { stage, step, tool } of FILL_TOOL_STEPS) {
+		it(`${tool} is allowed by both gates at ${stage}/${step}`, () => {
+			const policyAllowed = getAllowedPlannerWrapperTools({
+				stage,
+				step,
+				broken: false,
+				requiresUserDecision: false,
+				requiresCompact: false,
+				debugArtifactsDir: null,
+			});
+			expect(policyAllowed).toContain(tool);
+
+			const behaviorDecision = checkPlannerStageBehaviorWrapperTool({
+				behavior: getPlannerStageStepBehavior({ stage, step }),
+				tool,
+			});
+			expect(behaviorDecision.allow).toBe(true);
+		});
+	}
+});
diff --git a/src/runtime/stage-behavior.ts b/src/runtime/stage-behavior.ts
index bd8bffd..c1b325a 100644
--- a/src/runtime/stage-behavior.ts
+++ b/src/runtime/stage-behavior.ts
@@ -207,6 +207,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		requiredGates: ["plan_worktree_exists"],
 		expectedTools: [
 			"planner_status",
+			"planner_discovery_submit",
 			"planner_contract_scan",
 			"planner_contract_route",
 			"planner_contract_read",
@@ -256,12 +257,14 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		"draft_plan",
 		["plan.md"],
 		["discovery.md"],
+		["planner_plan_submit", "planner_contract_route", "planner_contract_read"],
 	),
 	split_tasks: artifactBehavior(
 		"planning",
 		"split_tasks",
 		["plan.md"],
 		["plan.md"],
+		["planner_contract_route", "planner_contract_read"],
 	),
 	write_task_files: behavior("planning", "write_task_files", {
 		projectAccess: "planner_artifacts",
@@ -314,6 +317,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		requiredGates: ["active_task_selected", "task_branch_ready"],
 		expectedTools: [
 			"planner_status",
+			"planner_tdd_submit",
 			"planner_report_stuck",
 			"planner_skill_create",
 			"planner_skill_update",
@@ -332,6 +336,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		updatedArtifacts: ["tdd.md"],
 		requiredGates: ["tdd_plan_written"],
 		expectedTools: [
+			"planner_tdd_submit",
 			"planner_git_inspect",
 			"planner_git_commit",
 			"planner_report_stuck",
@@ -353,6 +358,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		requiredGates: ["tests_written_first"],
 		expectedTools: [
 			"planner_status",
+			"planner_tdd_submit",
 			"planner_report_stuck",
 			"planner_skill_create",
 			"planner_skill_update",
@@ -371,6 +377,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		updatedArtifacts: ["tdd.md"],
 		requiredGates: ["failing_signal_recorded"],
 		expectedTools: [
+			"planner_tdd_submit",
 			"planner_git_commit",
 			"planner_contract_route",
 			"planner_contract_read",
@@ -392,6 +399,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		updatedArtifacts: ["tdd.md", "contracts/manifest.json"],
 		requiredGates: ["task_implemented"],
 		expectedTools: [
+			"planner_tdd_submit",
 			"planner_contract_check",
 			"planner_contract_upsert",
 			"planner_contract_route",
@@ -411,6 +419,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		updatedArtifacts: ["refactor.md"],
 		requiredGates: ["task_implemented", "contract_check_completed"],
 		expectedTools: [
+			"planner_tdd_submit",
 			"planner_refactor_review",
 			"planner_git_commit",
 			"planner_contract_check",
@@ -435,6 +444,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		updatedArtifacts: ["refactor.md"],
 		requiredGates: ["refactor_checked"],
 		expectedTools: [
+			"planner_tdd_submit",
 			"planner_git_commit",
 			"planner_report_stuck",
 			"planner_skill_create",
@@ -468,7 +478,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		requiredArtifacts: ["refactor.md"],
 		updatedArtifacts: ["state.json"],
 		requiredGates: ["final_tests_passed"],
-		expectedTools: ["planner_git_merge_task_to_plan"],
+		expectedTools: ["planner_tdd_submit", "planner_git_merge_task_to_plan"],
 		commitPolicy: "forbidden",
 		compactPolicy: "not_allowed",
 	}),
@@ -494,7 +504,11 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		requiredArtifacts: ["plan.md"],
 		updatedArtifacts: ["verify.md"],
 		requiredGates: ["next_task_decided"],
-		expectedTools: ["planner_git_inspect"],
+		expectedTools: [
+			"planner_git_inspect",
+			"planner_contract_route",
+			"planner_contract_read",
+		],
 		commitPolicy: "forbidden",
 		compactPolicy: "not_allowed",
 	}),
@@ -532,10 +546,13 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		requiredGates: ["plan_branch_verified"],
 		expectedTools: [
 			"planner_status",
+			"planner_summary_submit",
 			"planner_skill_create",
 			"planner_skill_update",
 			"planner_contract_check",
 			"planner_contract_upsert",
+			"planner_contract_route",
+			"planner_contract_read",
 		],
 		commitPolicy: "forbidden",
 		compactPolicy: "not_allowed",
@@ -558,6 +575,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 			"planner_status",
 			"planner_skill_create",
 			"planner_skill_update",
+			"planner_contract_decide",
 		],
 		commitPolicy: "forbidden",
 		compactPolicy: "not_allowed",
@@ -568,7 +586,7 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		requiredArtifacts: ["final_summary.md"],
 		updatedArtifacts: ["decisions.md"],
 		requiredGates: ["user_acceptance_required"],
-		expectedTools: ["planner_status"],
+		expectedTools: ["planner_status", "planner_contract_decide"],
 		commitPolicy: "forbidden",
 		compactPolicy: "not_allowed",
 	}),
@@ -578,7 +596,11 @@ export const PLANNER_STAGE_BEHAVIOR = {
 		requiredArtifacts: ["decisions.md"],
 		updatedArtifacts: ["plan.md", "decisions.md", "discovery.md", "state.json"],
 		requiredGates: ["user_acceptance_required"],
-		expectedTools: ["planner_finish_step"],
+		expectedTools: [
+			"planner_finish_step",
+			"planner_plan_submit",
+			"planner_discovery_submit",
+		],
 		commitPolicy: "forbidden",
 		compactPolicy: "not_allowed",
 	}),
@@ -738,6 +760,7 @@ function artifactBehavior(
 	step: PlannerStep,
 	updatedArtifacts: readonly PlannerBehaviorArtifact[],
 	requiredArtifacts: readonly PlannerBehaviorArtifact[],
+	extraTools: readonly string[] = [],
 ): PlannerStageStepBehavior {
 	return behavior(stage, step, {
 		projectAccess: "planner_artifacts",
@@ -745,7 +768,7 @@ function artifactBehavior(
 		requiredArtifacts,
 		updatedArtifacts,
 		requiredGates: [],
-		expectedTools: ["planner_status"],
+		expectedTools: ["planner_status", ...extraTools],
 		commitPolicy: "forbidden",
 		compactPolicy: "not_allowed",
 	});
diff --git a/src/runtime/tool-gating-invariant.test.ts b/src/runtime/tool-gating-invariant.test.ts
new file mode 100644
index 0000000..180a35f
--- /dev/null
+++ b/src/runtime/tool-gating-invariant.test.ts
@@ -0,0 +1,54 @@
+import { describe, expect, it } from "vitest";
+import {
+	getAllowedPlannerWrapperTools,
+	type PlannerWrapperTool,
+} from "../guard/tool-policy";
+import {
+	PLANNER_STAGE_STEPS,
+	type PlannerStage,
+	type PlannerStep,
+} from "../storage/schema";
+import {
+	checkPlannerStageBehaviorWrapperTool,
+	getPlannerStageStepBehavior,
+} from "./stage-behavior";
+
+// Invariant: a planner tool is usable at a step only if it passes BOTH gates —
+// the guard policy (STEP_ALLOWED_TOOLS) and the stage-behavior expectedTools
+// gate. So everything the guard permits MUST also pass the behavior gate;
+// otherwise the guard advertises a tool the model can never actually call
+// (a deadlock when no fallback exists, as happened with the artifact fill-tools).
+//
+// This guards against the two allowlists drifting apart for any tool — debug
+// wrappers, git wrappers, contract tools, skills, or future additions.
+describe("planner tool gating invariant", () => {
+	it("every guard-allowed wrapper passes the behavior gate at every step", () => {
+		const steps = Object.entries(PLANNER_STAGE_STEPS) as Array<
+			[PlannerStage, readonly PlannerStep[]]
+		>;
+		const violations: string[] = [];
+
+		for (const [stage, stepList] of steps) {
+			for (const step of stepList) {
+				// debugArtifactsDir set so debug wrappers are included in the guard
+				// set and therefore checked against the behavior gate too.
+				const allowed = getAllowedPlannerWrapperTools({
+					stage,
+					step,
+					broken: false,
+					requiresUserDecision: false,
+					requiresCompact: false,
+					debugArtifactsDir: "/tmp/planner-debug",
+				});
+				const behavior = getPlannerStageStepBehavior({ stage, step });
+				for (const tool of allowed as readonly PlannerWrapperTool[]) {
+					if (!checkPlannerStageBehaviorWrapperTool({ behavior, tool }).allow) {
+						violations.push(`${stage}/${step}: ${tool}`);
+					}
+				}
+			}
+		}
+
+		expect(violations, violations.join("\n")).toEqual([]);
+	});
+});