diff --git a/plugins/opencode-go-usage-source/server/stores.ts b/plugins/opencode-go-usage-source/server/stores.ts
index c3108055a7..658c854a55 100644
--- a/plugins/opencode-go-usage-source/server/stores.ts
+++ b/plugins/opencode-go-usage-source/server/stores.ts
@@ -28,7 +28,7 @@ const keySchema = z.object({ type: z.literal("key"), key: z.string().min(1) });
 export function defaultStorePaths(env: NodeJS.ProcessEnv = process.env): StorePaths {
   const dataHome = env.XDG_DATA_HOME || join(env.HOME || homedir(), ".local", "share");
   const directory = join(dataHome, "opencode");
-  const database = env.OPENCODE_DB ? resolve(env.OPENCODE_DB) : join(directory, "opencode.db");
+  const database = resolve(directory, env.OPENCODE_DB || "opencode.db");
   return { file: join(directory, "auth.json"), database };
 }
 
diff --git a/plugins/opencode-go-usage-source/server/usage.test.ts b/plugins/opencode-go-usage-source/server/usage.test.ts
index 022b150c17..18d44ab6fa 100644
--- a/plugins/opencode-go-usage-source/server/usage.test.ts
+++ b/plugins/opencode-go-usage-source/server/usage.test.ts
@@ -1,4 +1,4 @@
-import { mkdtemp, readFile, rm, writeFile } from "node:fs/promises";
+import { mkdir, mkdtemp, readFile, rm, writeFile } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import { dirname, join } from "node:path";
 import { afterEach, beforeEach, expect, test } from "vitest";
@@ -181,6 +181,34 @@ test("resolves default and overridden OpenCode store paths", () => {
   });
 });
 
+test("discovers a relative OPENCODE_DB under the OpenCode data directory", async () => {
+  const paths = defaultStorePaths({
+    XDG_DATA_HOME: fixtureDirectory,
+    OPENCODE_DB: "go.db",
+  });
+  const databasePath = join(fixtureDirectory, "opencode", "go.db");
+  await mkdir(dirname(databasePath));
+  const { DatabaseSync } = await import("node:sqlite");
+  const db = new DatabaseSync(databasePath);
+  db.exec(
+    "CREATE TABLE credential (id TEXT PRIMARY KEY, integration_id TEXT, value TEXT, active INTEGER, time_updated INTEGER)",
+  );
+  db.prepare("INSERT INTO credential VALUES (?, ?, ?, ?, ?)").run(
+    "go",
+    "opencode-go",
+    JSON.stringify({ type: "key", key: "relative-key" }),
+    1,
+    1,
+  );
+  db.close();
+  expect(await discover(paths)).toEqual([
+    {
+      key: expect.stringMatching(/^[a-f0-9]{64}$/),
+      input: { store: "database", path: databasePath },
+    },
+  ]);
+});
+
 test("discovers and fetches the default key from read-only auth.json", async () => {
   const directory = await mkdtemp(join(tmpdir(), "paseo-go-usage-"));
   const path = join(directory, "auth.json");