diff --git a/README.md b/README.md
index 14d70a5..0aa9980 100644
--- a/README.md
+++ b/README.md
@@ -347,7 +347,7 @@ Eso no indica que el bot “no funcione”: indica que el filtro económico es e
 
 - **Pre-commit:** Husky runs lint-staged (`eslint --fix`, `prettier --write`) on staged `*.ts` / `*.tsx` in `src/` and `web/src/`.
 - **API contracts:** Zod schemas per REST endpoint → OpenAPI via `@asteasolutions/zod-to-openapi` → Scalar UI at `/api-docs`. Request bodies validated with Zod in route handlers.
-- **Observability:** `@sentry/node` captures REST, WebSocket feed, and SSE errors; `pino` JSON logs with `correlationId` (from `x-request-id` or per book tick); OpenTelemetry spans (`ws.message` → `orderbook.process` → `arbitrage.evaluate` → `sse.broadcast`) export to Sentry via `@sentry/opentelemetry` when `SENTRY_DSN` is set.
+- **Observability:** `@sentry/node` captures REST, WebSocket feed, and SSE errors; `pino` JSON logs with `correlationId` (from `x-request-id` or per book tick); OpenTelemetry spans (`ws.message` → `orderbook.process` → `arbitrage.evaluate` → `sse.broadcast`) export to Sentry via `@sentry/opentelemetry` when `SENTRY_DSN` is set. Dev probe: `GET /api/debug/sentry`; verify with `npm run test:observability`.
 - **Rate limiting & cache:** Upstash sliding-window limits per IP on read/write/SSE routes (`429` + `Retry-After`). Latest `StateSnapshot` cached in Redis (~1s TTL) for `GET /api/state` and refreshed on SSE broadcast. Set `UPSTASH_REDIS_REST_URL` and `UPSTASH_REDIS_REST_TOKEN`.
 - **CI:** GitHub Actions quality pipeline (typecheck, unit tests, build); Playwright smoke on PRs — dashboard loads and SSE connects (`npm run test:e2e`, workflow `e2e.yml`, `DEMO_MODE=true` in CI).
 - **Security scanning:** CodeQL (`.github/workflows/codeql.yml`); Dependabot for npm (root + `web/`) and GitHub Actions.
diff --git a/e2e/observability.spec.ts b/e2e/observability.spec.ts
new file mode 100644
index 0000000..5fb3b67
--- /dev/null
+++ b/e2e/observability.spec.ts
@@ -0,0 +1,8 @@
+import { test, expect } from "@playwright/test";
+
+/** Asserts the dev Sentry probe responds; does not verify ingest in sentry.io (see README). */
+test("sentry dev probe returns ok", async ({ request }) => {
+  const res = await request.get("/api/debug/sentry");
+  expect(res.ok()).toBeTruthy();
+  await expect(res.json()).resolves.toMatchObject({ ok: true });
+});
diff --git a/package.json b/package.json
index 5cc4021..70194da 100644
--- a/package.json
+++ b/package.json
@@ -14,6 +14,7 @@
     "typecheck": "tsc --noEmit && npm --prefix web run typecheck",
     "test": "node scripts/run-tests.mjs",
     "test:e2e": "playwright test",
+    "test:observability": "playwright test observability.spec.ts",
     "lint": "eslint .",
     "prepare": "husky"
   },
diff --git a/src/index.ts b/src/index.ts
index 926a3fc..978a1bc 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,3 +1,4 @@
+import "./load-env.js";
 import { initInstrumentation } from "./instrumentation/index.js";
 
 initInstrumentation();
diff --git a/src/interfaces/http/routes.ts b/src/interfaces/http/routes.ts
index 8f035f1..ceabeb3 100644
--- a/src/interfaces/http/routes.ts
+++ b/src/interfaces/http/routes.ts
@@ -4,6 +4,7 @@ import {
   type Request,
   type Response,
 } from "express";
+import { Sentry } from "../../instrumentation/sentry.js";
 import type { ApplicationService } from "../../composition/application-service.js";
 import {
   bindRequestCorrelation,
@@ -39,6 +40,15 @@ export function createRouter(app: ApplicationService, sse: SseHub): Router {
     res.json({ success: true, data: { status: "ok", ts: Date.now() } });
   });
 
+  router.get("/debug/sentry", (_req: Request, res: Response) => {
+    if (process.env.NODE_ENV === "production") {
+      res.status(404).json({ error: "Not found" });
+      return;
+    }
+    Sentry.captureException(new Error("Arb Pulse Sentry test error"));
+    res.json({ ok: true, message: "Test error sent to Sentry" });
+  });
+
   router.get("/state", async (_req: Request, res: Response) => {
     const cached =
       await getCachedSnapshot<ReturnType<ApplicationService["getSnapshot"]>>();
diff --git a/src/load-env.ts b/src/load-env.ts
new file mode 100644
index 0000000..48351c9
--- /dev/null
+++ b/src/load-env.ts
@@ -0,0 +1,9 @@
+import { existsSync } from "node:fs";
+import { loadEnvFile } from "node:process";
+
+for (const file of [".env.local", ".env"]) {
+  if (existsSync(file)) {
+    loadEnvFile(file);
+    break;
+  }
+}