feat(config): follow XDG Base Directory spec for config location

apps/cli-docs/src/content/docs/getting-started.mdx

@@ -112,8 +112,9 @@ sentry auth
 You'll be given a URL and a code to enter. Once you authorize the application
 in your browser, the CLI stores the OAuth credentials. When the server provides
 a refresh token, the CLI refreshes the access token automatically. Persist the
-Sentry CLI configuration directory (`~/.sentry/` by default, overridable with
-`SENTRY_CONFIG_DIR`) across runs to keep automatic refresh working.
+Sentry CLI configuration directory (`$XDG_CONFIG_HOME/sentry/`, defaulting to
+`~/.config/sentry/`, overridable with `SENTRY_CONFIG_DIR`) across runs to keep
+automatic refresh working.
 
 ### API Token
 
@@ -156,7 +157,7 @@ See the [Self-Hosted](../self-hosted/) guide for full setup details.
 
 ## Configuration
 
-Credentials are stored in a SQLite database at `~/.sentry/` with restricted file permissions (mode 600) for security. See [Configuration](../configuration/) for environment variables and customization options.
+Credentials are stored in a SQLite database under `$XDG_CONFIG_HOME/sentry/` (defaulting to `~/.config/sentry/`) with restricted file permissions (mode 600) for security. See [Configuration](../configuration/) for environment variables and customization options.
 
 ## Next Steps
 

apps/cli-docs/src/fragments/configuration.md

@@ -103,7 +103,7 @@ The `sentry api` command also uses `--verbose` to show full HTTP request/respons
 
 ## Credential Storage
 
-We store credentials and caches in a SQLite database (`cli.db`) inside the config directory (`~/.sentry/` by default, overridable via `SENTRY_CONFIG_DIR`). The database file and its WAL side-files are created with restricted permissions (mode 600) so that only the current user can read them. The database also caches:
+We store credentials and caches in a SQLite database (`cli.db`) inside the config directory. The location follows the [XDG Base Directory specification](https://specifications.freedesktop.org/basedir/latest/): by default the CLI uses `$XDG_CONFIG_HOME/sentry` (i.e. `~/.config/sentry/` when `XDG_CONFIG_HOME` is unset), and you can override it with `SENTRY_CONFIG_DIR`. For backward compatibility, if a legacy `~/.sentry/` directory already exists it continues to be used. The database file and its WAL side-files are created with restricted permissions (mode 600) so that only the current user can read them. The database also caches:
 
 - Organization and project defaults
 - DSN resolution results

packages/cli/README.md

@@ -78,7 +78,7 @@ Run `sentry --help` to see all available commands, or browse the [command refere
 
 ## Configuration
 
-Credentials are stored in `~/.sentry/` with restricted permissions (mode 600).
+Credentials are stored in `$XDG_CONFIG_HOME/sentry/` (defaulting to `~/.config/sentry/`) with restricted permissions (mode 600). A pre-existing legacy `~/.sentry/` directory is still honored, and the location can be overridden with `SENTRY_CONFIG_DIR`.
 
 ## Library Usage
 

packages/cli/src/lib/db/index.ts

@@ -4,10 +4,10 @@
  * bundled WASM driver (`node-sqlite3-wasm`, Node < 22.15) behind one API.
  */
 
-import { chmodSync, mkdirSync } from "node:fs";
+import { chmodSync, existsSync, mkdirSync } from "node:fs";
 import { createRequire } from "node:module";
 import { homedir } from "node:os";
-import { join } from "node:path";
+import { isAbsolute, join } from "node:path";
 import { getEnv } from "../env.js";
 import { logger } from "../logger.js";
 
@@ -21,7 +21,11 @@ import { Database } from "./sqlite.js";
 
 export const CONFIG_DIR_ENV_VAR = "SENTRY_CONFIG_DIR";
 
-const DEFAULT_CONFIG_DIR_NAME = ".sentry";
+/** Legacy config directory name under the user's home directory (`~/.sentry`). */
+const LEGACY_CONFIG_DIR_NAME = ".sentry";
+
+/** Sub-directory used under the XDG config base directory. */
+const XDG_CONFIG_SUBDIR = "sentry";
 
 const DB_FILENAME = "cli.db";
 
@@ -69,10 +73,40 @@ function registerExitHandler(): void {
   });
 }
 
+/**
+ * Resolve the config directory from an environment and home directory.
+ *
+ * Precedence:
+ * 1. `SENTRY_CONFIG_DIR` — explicit override, always wins.
+ * 2. Legacy `~/.sentry` — used when it already exists, so existing installs
+ *    keep working without migration.
+ * 3. XDG base directory — `$XDG_CONFIG_HOME/sentry`, falling back to
+ *    `~/.config/sentry`. Per the XDG spec, a non-absolute `XDG_CONFIG_HOME`
+ *    is ignored.
+ *
+ * Pure and side-effect free so it can be unit-tested directly.
+ */
+export function resolveConfigDir(env: NodeJS.ProcessEnv, home: string): string {
+  const override = env[CONFIG_DIR_ENV_VAR];
+  if (override) {
+    return override;
+  }
+
+  const legacyDir = join(home, LEGACY_CONFIG_DIR_NAME);
+  if (existsSync(legacyDir)) {
+    return legacyDir;
+  }
+
+  const xdgConfigHome = env.XDG_CONFIG_HOME;
+  const configHome =
+    xdgConfigHome && isAbsolute(xdgConfigHome)
+      ? xdgConfigHome
+      : join(home, ".config");
+  return join(configHome, XDG_CONFIG_SUBDIR);
+}
+
 export function getConfigDir(): string {
-  return (
-    getEnv()[CONFIG_DIR_ENV_VAR] || join(homedir(), DEFAULT_CONFIG_DIR_NAME)
-  );
+  return resolveConfigDir(getEnv(), homedir());
 }
 
 export function getDbPath(): string {

packages/cli/test/lib/config.test.ts

@@ -4,8 +4,9 @@
  * Integration tests for SQLite-based config storage.
  */
 
-import { writeFileSync } from "node:fs";
-import { access } from "node:fs/promises";
+import { mkdirSync, writeFileSync } from "node:fs";
+import { access, mkdtemp, rm } from "node:fs/promises";
+import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { afterEach, beforeEach, describe, expect, test } from "vitest";
 import {
@@ -26,6 +27,7 @@ import {
   CONFIG_DIR_ENV_VAR,
   closeDatabase,
   getDbPath,
+  resolveConfigDir,
 } from "../../src/lib/db/index.js";
 import {
   clearProjectAliases,
@@ -561,6 +563,54 @@ describe("getDbPath", () => {
   });
 });
 
+describe("resolveConfigDir", () => {
+  let home: string;
+
+  beforeEach(async () => {
+    home = await mkdtemp(join(tmpdir(), "resolve-config-home-"));
+  });
+
+  afterEach(async () => {
+    await rm(home, { recursive: true, force: true });
+  });
+
+  test("prefers the SENTRY_CONFIG_DIR override over everything", () => {
+    const override = join(home, "custom-config");
+    mkdirSync(join(home, ".sentry"));
+    expect(
+      resolveConfigDir(
+        {
+          [CONFIG_DIR_ENV_VAR]: override,
+          XDG_CONFIG_HOME: join(home, "xdg"),
+        },
+        home
+      )
+    ).toBe(override);
+  });
+
+  test("uses the legacy ~/.sentry directory when it already exists", () => {
+    mkdirSync(join(home, ".sentry"));
+    expect(resolveConfigDir({}, home)).toBe(join(home, ".sentry"));
+  });
+
+  test("uses XDG_CONFIG_HOME/sentry when set to an absolute path", () => {
+    const xdg = join(home, "xdg-config");
+    expect(resolveConfigDir({ XDG_CONFIG_HOME: xdg }, home)).toBe(
+      join(xdg, "sentry")
+    );
+  });
+
+  test("falls back to ~/.config/sentry when XDG_CONFIG_HOME is unset", () => {
+    expect(resolveConfigDir({}, home)).toBe(join(home, ".config", "sentry"));
+  });
+
+  test("ignores a non-absolute XDG_CONFIG_HOME per the XDG spec", () => {
+    expect(resolveConfigDir({ XDG_CONFIG_HOME: "relative/path" }, home)).toBe(
+      join(home, ".config", "sentry")
+    );
+  });
+});
+
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 // JSON Migration
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