@@ -681,6 +681,14 @@ describe("GET /api/v1/vaults", () => {
     });
   });
 
+  it("rejects non-GET methods with 405", async () => {
+    const res = makeRes();
+    await vaultsHandler(fakeReq({ method: "POST" }), res);
+    expect(res.statusCode).toBe(405);
+    expect(res.headers["Allow"]).toBe("GET");
+    expect(fetchAllVaults).not.toHaveBeenCalled();
+  });
+
   it("reports cached: true when served from cache", async () => {
     vi.mocked(fetchVaultsWithCache).mockResolvedValueOnce({
       vaults: [
@@ -748,6 +756,17 @@ describe("GET /api/v1/vaults/:vaultId", () => {
     expect(res.statusCode).toBe(404);
     expect(res.headers["Cache-Control"]).toBeUndefined();
   });
+
+  it("rejects non-GET methods with 405", async () => {
+    const res = makeRes();
+    await vaultDetailHandler(
+      fakeReq({ method: "POST", query: { vaultId: "meridian-usdc" } }),
+      res
+    );
+    expect(res.statusCode).toBe(405);
+    expect(res.headers["Allow"]).toBe("GET");
+    expect(fetchAllVaults).not.toHaveBeenCalled();
+  });
 });
 
 describe("GET /api/v1/positions/:publicKey", () => {
@@ -761,6 +780,17 @@ describe("GET /api/v1/positions/:publicKey", () => {
     expect(resolvePositions).not.toHaveBeenCalled();
   });
 
+  it("rejects non-GET methods with 405", async () => {
+    const res = makeRes();
+    await positionsHandler(
+      fakeReq({ method: "POST", query: { publicKey: PUBKEY } }),
+      res
+    );
+    expect(res.statusCode).toBe(405);
+    expect(res.headers["Allow"]).toBe("GET");
+    expect(resolvePositions).not.toHaveBeenCalled();
+  });
+
   it("returns the resolved positions for a valid key", async () => {
     const res = makeRes();
     await positionsHandler(
@@ -1489,4 +1519,20 @@ describe("GET /api/v1/admin/vault-state", () => {
 
     expect(res.statusCode).toBe(503);
   });
+
+  it("rejects non-GET methods with 405", async () => {
+    const res = makeRes();
+    await adminHandler(
+      fakeReq({
+        query: { resource: "vault-state" },
+        method: "POST",
+        headers: {},
+      }),
+      res
+    );
+
+    expect(res.statusCode).toBe(405);
+    expect(res.headers["Allow"]).toBe("GET");
+    expect(fetchCoordinatorState).not.toHaveBeenCalled();
+  });
 });
@@ -5,6 +5,7 @@ import {
   checkRateLimit,
   isCronAuthorized,
   isCronSecretConfigured,
+  requireGetMethod,
   resetRateLimitForTesting,
 } from "../_lib/middleware.js";
 
@@ -98,6 +99,25 @@ describe("applyCors", () => {
   });
 });
 
+// requireGetMethod ----------------------------------------------------------------
+
+describe("requireGetMethod", () => {
+  it("allows GET requests without writing a response", () => {
+    const res = fakeRes();
+    expect(requireGetMethod(fakeReq("GET"), res)).toBe(false);
+    expect(res.statusCode).toBe(200);
+    expect(res.ended).toBe(false);
+  });
+
+  it("returns 405 with an Allow header for non-GET requests", () => {
+    const res = fakeRes();
+    expect(requireGetMethod(fakeReq("POST"), res)).toBe(true);
+    expect(res.statusCode).toBe(405);
+    expect(res.headers["Allow"]).toBe("GET");
+    expect(res.body).toEqual({ error: "Method not allowed" });
+  });
+});
+
 // checkRateLimit ------------------------------------------------------------------
 
 describe("checkRateLimit", () => {
 
@@ -76,6 +76,21 @@ export function applyCors(req: VercelRequest, res: VercelResponse): boolean {
   return false;
 }
 
+/**
+ * Reject any method other than GET on a read-only route. Returns true when a
+ * 405 has already been sent, so callers use `if (requireGetMethod(req, res))
+ * return;`.
+ */
+export function requireGetMethod(
+  req: VercelRequest,
+  res: VercelResponse
+): boolean {
+  if (req.method === "GET") return false;
+  res.setHeader("Allow", "GET");
+  res.status(405).json({ error: "Method not allowed" });
+  return true;
+}
+
 // Cache policy shared by both vault-read endpoints: the list in
 // v1/vaults/index.ts and the single-vault read in v1/vaults/[vaultId].ts.
 // Both must use the same policy — #1051 happened because the detail endpoint
 
@@ -1,6 +1,10 @@
 import type { VercelRequest, VercelResponse } from "@vercel/node";
 import { handleGetAdminHistory, handleGetVaultState } from "@meridian/api-core";
-import { applyCors, checkRateLimit } from "../../_lib/middleware.js";
+import {
+  applyCors,
+  checkRateLimit,
+  requireGetMethod,
+} from "../../_lib/middleware.js";
 
 const HISTORY_CACHE_CONTROL = "public, s-maxage=30, stale-while-revalidate=120";
 
@@ -25,17 +29,15 @@ export default async function handler(req: VercelRequest, res: VercelResponse) {
   const { resource } = req.query;
 
   if (resource === "vault-state") {
+    if (requireGetMethod(req, res)) return;
     const result = await handleGetVaultState();
     if (result.error) console.error("[admin/vault-state] error:", result.error);
     res.setHeader("Cache-Control", "no-store");
     return res.status(result.status).json(result.body);
   }
 
   if (resource === "history") {
-    if (req.method !== "GET") {
-      res.setHeader("Allow", "GET");
-      return res.status(405).json({ error: "Method not allowed" });
-    }
+    if (requireGetMethod(req, res)) return;
     const raw = req.query["vaultId"];
     const vaultId = typeof raw === "string" ? raw : undefined;
     if (!vaultId) return res.status(400).json({ error: "vaultId is required" });
 
@@ -25,19 +25,21 @@ import {
   isCronSecretConfigured,
 } from "../../_lib/middleware.js";
 
-// Consolidated from four separate files (accrue/health/rebalance/alert) to
-// stay under Vercel's per-deployment Serverless Functions cap. URL paths are
-// unchanged: /api/v1/keepers/accrue, /api/v1/keepers/health,
-// /api/v1/keepers/rebalance, and /api/v1/keepers/alert all route here via
-// the [action].ts dynamic segment, with req.query.action set accordingly.
+// Consolidated from the former per-keeper files to stay under Vercel's
+// per-deployment Serverless Functions cap. URL paths are unchanged:
+// /api/v1/keepers/accrue, /api/v1/keepers/health,
+// /api/v1/keepers/rebalance, /api/v1/keepers/alert, and
+// /api/v1/keepers/snapshot all route here via the [action].ts dynamic
+// segment, with req.query.action set accordingly.
 //
-// health is read-only and public, same as before; accrue/rebalance/alert
-// still require the cron bearer token and are never CORS-gated. accrue and
-// rebalance sign and submit real transactions off a funded/admin account;
-// alert signs nothing but still costs an RPC round trip per known vault plus
-// a webhook POST per unauthenticated probe, so it gets the same rate-limit
-// backstop. That auth split is preserved exactly as it was when these were
-// separate files.
+// health is read-only and public, same as before; accrue/rebalance/alert/
+// snapshot still require the cron bearer token and are never CORS-gated.
+// accrue and rebalance sign and submit real transactions off a funded/admin
+// account; alert signs nothing but still costs an RPC round trip per known
+// vault plus a webhook POST per unauthenticated probe; snapshot reads every
+// tracked wallet and writes the resulting series. They all keep the same
+// rate-limit backstop. That auth split is preserved exactly as it was when
+// these were separate files.
 export default async function handler(req: VercelRequest, res: VercelResponse) {
   const { action } = req.query;
 
@@ -71,14 +73,14 @@ export default async function handler(req: VercelRequest, res: VercelResponse) {
     return res.status(405).json({ error: "Method not allowed" });
   }
 
-  // No applyCors: cron-invoked, never browser-facing. But all three sign or
-  // submit real transactions, or read/post on their behalf, unlike simple
-  // reads, so they still get a rate-limit backstop. Checked before auth,
-  // deliberately, even though that costs a Redis round trip on an
+  // No applyCors: cron-invoked, never browser-facing. But these actions sign
+  // or submit real transactions, or read and write on their behalf, unlike
+  // simple reads, so they still get a rate-limit backstop. Checked before
+  // auth, deliberately, even though that costs a Redis round trip on an
   // unauthenticated probe: this is the volume-abuse backstop for *all*
-  // traffic, not just correctly authenticated traffic — if it only ran
-  // after a successful auth check, unauthenticated/wrong-token spam would
-  // be entirely unbounded.
+  // traffic, not just correctly authenticated traffic. If it only ran after
+  // a successful auth check, unauthenticated or wrong-token spam would be
+  // entirely unbounded.
   try {
     if (!(await checkRateLimit(req, res, { strict: true }))) return;
   } catch (err) {
 
@@ -1,9 +1,14 @@
 import type { VercelRequest, VercelResponse } from "@vercel/node";
 import { handleGetPositions } from "@meridian/api-core";
-import { applyCors, checkRateLimit } from "../../_lib/middleware.js";
+import {
+  applyCors,
+  checkRateLimit,
+  requireGetMethod,
+} from "../../_lib/middleware.js";
 
 export default async function handler(req: VercelRequest, res: VercelResponse) {
   if (applyCors(req, res)) return;
+  if (requireGetMethod(req, res)) return;
   try {
     if (!(await checkRateLimit(req, res))) return;
   } catch (err) {
 
@@ -4,6 +4,7 @@ import { handleGetVaultById } from "@meridian/api-core";
 import {
   applyCors,
   checkRateLimit,
+  requireGetMethod,
   vaultReadCacheControl,
 } from "../../_lib/middleware.js";
 
@@ -16,6 +17,7 @@ const KNOWN_VAULT_IDS = new Set(
 
 export default async function handler(req: VercelRequest, res: VercelResponse) {
   if (applyCors(req, res)) return;
+  if (requireGetMethod(req, res)) return;
   try {
     if (!(await checkRateLimit(req, res))) return;
   } catch (err) {
 
@@ -3,11 +3,13 @@ import { handleGetVaults } from "@meridian/api-core";
 import {
   applyCors,
   checkRateLimit,
+  requireGetMethod,
   vaultReadCacheControl,
 } from "../../_lib/middleware.js";
 
 export default async function handler(req: VercelRequest, res: VercelResponse) {
   if (applyCors(req, res)) return;
+  if (requireGetMethod(req, res)) return;
   try {
     if (!(await checkRateLimit(req, res))) return;
   } catch (err) {
 
@@ -4,11 +4,16 @@ import { adminRoute } from "../routes/admin.js";
 import { keepersRoute } from "../routes/keepers.js";
 
 vi.mock("@meridian/api-core", () => ({
+  handleGetAdminHistory: vi.fn(),
   handleGetVaultState: vi.fn(),
   handleGetKeeperHealth: vi.fn(),
 }));
 
-import { handleGetVaultState, handleGetKeeperHealth } from "@meridian/api-core";
+import {
+  handleGetAdminHistory,
+  handleGetVaultState,
+  handleGetKeeperHealth,
+} from "@meridian/api-core";
 
 function buildApp() {
   const app = Fastify({ logger: false });
@@ -115,6 +120,58 @@ describe("GET /api/v1/admin/vault-state", () => {
   });
 });
 
+describe("GET /api/v1/admin/history", () => {
+  it("returns admin actions for the requested vault", async () => {
+    const app = buildApp();
+    const actions = [{ action: "pause", ledger: 42 }];
+    vi.mocked(handleGetAdminHistory).mockResolvedValue({
+      status: 200,
+      body: { vaultId: "meridian-usdc", actions },
+    });
+
+    const res = await app.inject({
+      method: "GET",
+      url: "/api/v1/admin/history?vaultId=meridian-usdc",
+    });
+    expect(res.statusCode).toBe(200);
+    expect(res.json()).toEqual({ vaultId: "meridian-usdc", actions });
+    expect(handleGetAdminHistory).toHaveBeenCalledWith("meridian-usdc");
+  });
+
+  it("returns 400 without calling the handler when vaultId is missing", async () => {
+    const app = buildApp();
+    const res = await app.inject({
+      method: "GET",
+      url: "/api/v1/admin/history",
+    });
+    expect(res.statusCode).toBe(400);
+    expect(res.json()).toEqual({ error: "vaultId is required" });
+    expect(handleGetAdminHistory).not.toHaveBeenCalled();
+  });
+
+  it("returns the handler status and logs an error", async () => {
+    const app = buildApp();
+    const logError = vi.spyOn(app.log, "error");
+    const err = new Error("horizon unavailable");
+    vi.mocked(handleGetAdminHistory).mockResolvedValue({
+      status: 500,
+      body: { error: "Failed to fetch admin history" },
+      error: err,
+    });
+
+    const res = await app.inject({
+      method: "GET",
+      url: "/api/v1/admin/history?vaultId=meridian-usdc",
+    });
+    expect(res.statusCode).toBe(500);
+    expect(res.json()).toEqual({ error: "Failed to fetch admin history" });
+    expect(logError).toHaveBeenCalledWith(
+      err,
+      "[admin] failed to read admin history"
+    );
+  });
+});
+
 describe("GET /api/v1/keepers/health", () => {
   it("returns 200 with the keeper health report", async () => {
     const app = buildApp();