diff --git a/.craft.yml b/.craft.yml
index 84d213dbf..3b1b181bb 100644
--- a/.craft.yml
+++ b/.craft.yml
@@ -26,6 +26,9 @@ targets:
   - name: npm
     id: "@sentry/junior-notion"
     includeNames: /^sentry-junior-notion-\d.*\.tgz$/
+  - name: npm
+    id: "@sentry/junior-scheduler"
+    includeNames: /^sentry-junior-scheduler-\d.*\.tgz$/
   - name: npm
     id: "@sentry/junior-sentry"
     includeNames: /^sentry-junior-sentry-\d.*\.tgz$/
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f8cf651e4..febc40832 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -58,6 +58,7 @@ jobs:
           pnpm --filter @sentry/junior-hex pack --pack-destination artifacts
           pnpm --filter @sentry/junior-linear pack --pack-destination artifacts
           pnpm --filter @sentry/junior-notion pack --pack-destination artifacts
+          pnpm --filter @sentry/junior-scheduler pack --pack-destination artifacts
           pnpm --filter @sentry/junior-sentry pack --pack-destination artifacts
           ls -la artifacts
 
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 284863e88..b7b40252e 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -67,6 +67,7 @@ This repo uses Craft for manual lockstep npm releases of:
 - `@sentry/junior-hex`
 - `@sentry/junior-linear`
 - `@sentry/junior-notion`
+- `@sentry/junior-scheduler`
 - `@sentry/junior-sentry`
 
 Run `pnpm release:check` before changing release package lists so `.craft.yml`, CI,
diff --git a/README.md b/README.md
index 0bad762c4..d7b0bde86 100644
--- a/README.md
+++ b/README.md
@@ -30,4 +30,5 @@ Start here:
 | `@sentry/junior-hex`           | Hex plugin package for data warehouse query workflows                        |
 | `@sentry/junior-linear`        | Linear plugin package for issue workflows                                    |
 | `@sentry/junior-notion`        | Notion plugin package for page search workflows                              |
+| `@sentry/junior-scheduler`     | Scheduler plugin package for scheduled Junior tasks                          |
 | `@sentry/junior-sentry`        | Sentry plugin package for issue workflows                                    |
diff --git a/apps/example/README.md b/apps/example/README.md
index 89a978893..5fb834fdf 100644
--- a/apps/example/README.md
+++ b/apps/example/README.md
@@ -28,7 +28,7 @@ Copy `.env.example` and set:
 - `AI_VISION_MODEL` (optional, enables image-understanding; unset disables vision features)
 - `AI_WEB_SEARCH_MODEL` (optional, overrides the `webSearch` tool model; defaults to a search-tuned model)
 - `JUNIOR_SECRET` (required outside `pnpm dev`; the local wrapper supplies a dev-only secret when unset)
-- `JUNIOR_SCHEDULER_SECRET` or `CRON_SECRET` (optional for `pnpm dev`; the local wrapper supplies a dev-only secret when both are unset)
+- `JUNIOR_SCHEDULER_SECRET` or `CRON_SECRET` (optional for `pnpm dev`; the local wrapper supplies a dev-only heartbeat secret when both are unset)
 - `NOTION_TOKEN` (optional, enables the bundled Notion plugin)
 
 ## Wiring
@@ -36,4 +36,4 @@ Copy `.env.example` and set:
 - `plugin-packages.ts` is the single source of truth for installed plugin packages in this app
 - `nitro.config.ts` passes that list to `juniorNitro()` so plugin content is copied into the build output
 - `server.ts` passes the same list to `createApp()` so local dev does not depend on Nitro's virtual config path for plugin discovery
-- root `pnpm dev` starts a local heartbeat loop that calls `/api/internal/heartbeat` every minute, matching the production cron pulse used by the built-in scheduler plugin; it also defaults `JUNIOR_BASE_URL` to the local server when unset so signed internal callbacks can recover scheduled dispatches
+- root `pnpm dev` starts a local heartbeat loop that calls `/api/internal/heartbeat` every minute, matching the production cron pulse used for trusted plugin heartbeats and stale dispatch recovery; it also defaults `JUNIOR_BASE_URL` to the local server when unset so signed internal callbacks can recover dispatched runs
diff --git a/package.json b/package.json
index fa83fcca4..aea853c67 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "test:watch": "pnpm --filter @sentry/junior test:watch",
     "evals": "pnpm --filter @sentry/junior-evals evals",
     "evals:record": "pnpm --filter @sentry/junior-evals evals:record",
-    "typecheck": "pnpm --filter @sentry/junior typecheck && pnpm --filter @sentry/junior-testing typecheck && pnpm --filter @sentry/junior-example typecheck",
+    "typecheck": "pnpm --filter @sentry/junior-plugin-api typecheck && pnpm --filter @sentry/junior-scheduler typecheck && pnpm --filter @sentry/junior typecheck && pnpm --filter @sentry/junior-testing typecheck && pnpm --filter @sentry/junior-example typecheck",
     "skills:check": "pnpm --filter @sentry/junior skills:check"
   },
   "simple-git-hooks": {
diff --git a/packages/docs/src/content/docs/contribute/releasing.md b/packages/docs/src/content/docs/contribute/releasing.md
index d94b4ad1a..ea90f36f6 100644
--- a/packages/docs/src/content/docs/contribute/releasing.md
+++ b/packages/docs/src/content/docs/contribute/releasing.md
@@ -19,6 +19,7 @@ Junior uses lockstep package releases for:
 - `@sentry/junior-hex`
 - `@sentry/junior-linear`
 - `@sentry/junior-notion`
+- `@sentry/junior-scheduler`
 - `@sentry/junior-sentry`
 
 ## Package release
diff --git a/packages/docs/src/content/docs/extend/index.md b/packages/docs/src/content/docs/extend/index.md
index db7fe0aa7..87d094c87 100644
--- a/packages/docs/src/content/docs/extend/index.md
+++ b/packages/docs/src/content/docs/extend/index.md
@@ -54,12 +54,9 @@ my-junior-plugin/
 For reuse across apps or teams, package plugin manifests and any bundled skills as npm packages and install them next to `@sentry/junior`.
 
 ```bash
-pnpm add @sentry/junior @sentry/junior-agent-browser @sentry/junior-datadog @sentry/junior-github @sentry/junior-hex @sentry/junior-linear @sentry/junior-notion @sentry/junior-sentry
+pnpm add @sentry/junior @sentry/junior-agent-browser @sentry/junior-datadog @sentry/junior-github @sentry/junior-hex @sentry/junior-linear @sentry/junior-notion @sentry/junior-scheduler @sentry/junior-sentry
 ```
 
-Junior also includes the built-in [Scheduler Plugin](/extend/scheduler-plugin/)
-for reminders and recurring Slack tasks. It does not require a separate package.
-
 List the plugin packages in `juniorNitro` so they are bundled at build time and available at runtime:
 
 ```ts title="nitro.config.ts"
@@ -78,6 +75,7 @@ export default defineConfig({
           "@sentry/junior-hex",
           "@sentry/junior-linear",
           "@sentry/junior-notion",
+          "@sentry/junior-scheduler",
           "@sentry/junior-sentry",
         ],
       },
@@ -115,18 +113,20 @@ If you publish your own package with bundled skills, include both `plugin.yaml`
 
 Some packaged plugins also export trusted runtime hooks for deterministic
 behavior that cannot live in skill prose or `plugin.yaml`. For example, the
-GitHub plugin registers runtime code that installs a sandbox Git hook,
-configures global Git defaults, and injects commit attribution env before bash
-commands run.
+scheduler plugin registers schedule-management tools and heartbeat behavior, and
+the GitHub plugin installs a sandbox Git hook, configures global Git defaults,
+and injects commit attribution env before bash commands run.
 
 Trusted hooks are explicit app code:
 
 ```ts title="server.ts"
 import { createApp } from "@sentry/junior";
 import { githubPlugin } from "@sentry/junior-github";
+import { schedulerPlugin } from "@sentry/junior-scheduler";
 
 const app = await createApp({
   plugins: [
+    schedulerPlugin(),
     githubPlugin({
       botNameEnv: "GITHUB_APP_BOT_NAME",
       botEmailEnv: "GITHUB_APP_BOT_EMAIL",
@@ -331,7 +331,7 @@ Then install it in the host app:
 pnpm add @acme/junior-example
 ```
 
-The `juniorNitro({ plugins: { packages: [...] } })` module includes `app/**/*` and the declared plugin package content in the deployed function bundle. The plugin list is automatically available at runtime via `createApp()` for declarative manifest behavior. Plugins that export trusted runtime hooks, such as `@sentry/junior-github`, must also be registered from app code.
+The `juniorNitro({ plugins: { packages: [...] } })` module includes `app/**/*` and the declared plugin package content in the deployed function bundle. The plugin list is automatically available at runtime via `createApp()` for declarative manifest behavior. Plugins that export trusted runtime hooks, such as `@sentry/junior-scheduler` and `@sentry/junior-github`, must also be registered from app code.
 
 ## Validate extensions
 
diff --git a/packages/docs/src/content/docs/extend/scheduler-plugin.md b/packages/docs/src/content/docs/extend/scheduler-plugin.md
index 5e0ba7f1e..dc4b51800 100644
--- a/packages/docs/src/content/docs/extend/scheduler-plugin.md
+++ b/packages/docs/src/content/docs/extend/scheduler-plugin.md
@@ -1,8 +1,8 @@
 ---
 title: Scheduler Plugin
-description: Enable and verify Junior's built-in scheduled task support.
+description: Enable and verify Junior's scheduled task support.
 type: tutorial
-summary: Configure the built-in scheduler plugin so Slack users can create reminders and recurring tasks.
+summary: Configure the scheduler plugin so Slack users can create reminders and recurring tasks.
 prerequisites:
   - /start-here/quickstart/
   - /start-here/slack-app-setup/
@@ -12,20 +12,39 @@ related:
   - /operate/reliability-runbooks/
 ---
 
-The scheduler plugin is built into `@sentry/junior`. It registers Slack tools for creating, listing, updating, deleting, and running scheduled tasks, then uses Junior's internal heartbeat to dispatch due work back to the configured Slack conversation.
+The scheduler plugin lives in `@sentry/junior-scheduler`. It registers Slack tools for creating, listing, updating, deleting, and running scheduled tasks, then uses Junior's internal heartbeat to dispatch due work back to the configured Slack conversation.
 
 ## Runtime setup
 
-No plugin package install is required. `createApp()` registers the trusted scheduler plugin automatically:
+Install the package next to `@sentry/junior`:
+
+```bash
+pnpm add @sentry/junior-scheduler
+```
+
+Register the trusted plugin in app code:
 
 ```ts title="server.ts"
 import { createApp } from "@sentry/junior";
+import { schedulerPlugin } from "@sentry/junior-scheduler";
 
-const app = await createApp();
+const app = await createApp({
+  plugins: [schedulerPlugin()],
+});
 
 export default app;
 ```
 
+List the package in `juniorNitro()` as well so Nitro bundles the manifest:
+
+```ts title="nitro.config.ts"
+juniorNitro({
+  plugins: {
+    packages: ["@sentry/junior-scheduler"],
+  },
+});
+```
+
 The scaffolded `vercel.json` includes the internal heartbeat route:
 
 ```json title="vercel.json"
@@ -47,14 +66,14 @@ If you manage routes manually, call the heartbeat route on a one-minute cadence:
 
 ## Configure environment variables
 
-Set one scheduler route secret:
+Set one heartbeat route secret:
 
-| Variable                                   | Required   | Purpose                                                                                       |
-| ------------------------------------------ | ---------- | --------------------------------------------------------------------------------------------- |
-| `CRON_SECRET` or `JUNIOR_SCHEDULER_SECRET` | Production | Bearer token for internal scheduler and heartbeat routes. Use `CRON_SECRET` with Vercel Cron. |
-| `JUNIOR_TIMEZONE`                          | No         | Default IANA timezone for schedule authoring. Defaults to `America/Los_Angeles`.              |
+| Variable                                   | Required   | Purpose                                                                            |
+| ------------------------------------------ | ---------- | ---------------------------------------------------------------------------------- |
+| `CRON_SECRET` or `JUNIOR_SCHEDULER_SECRET` | Production | Bearer token for the internal heartbeat route. Use `CRON_SECRET` with Vercel Cron. |
+| `JUNIOR_TIMEZONE`                          | No         | Default IANA timezone for schedule authoring. Defaults to `America/Los_Angeles`.   |
 
-Local development can run without a scheduler route secret when you call the dev server directly. Production deployments should set `CRON_SECRET` or `JUNIOR_SCHEDULER_SECRET`.
+Local development can run without a heartbeat route secret when you call the dev server directly. Production deployments should set `CRON_SECRET` or `JUNIOR_SCHEDULER_SECRET`.
 
 ## Verify
 
@@ -80,4 +99,4 @@ For recurring or non-reminder scheduled work, Junior should show the proposed ta
 
 ## Next step
 
-Read [Build a Plugin](/extend/build-a-plugin/) for the trusted `tools(ctx)` and `heartbeat(ctx)` APIs that the built-in scheduler uses.
+Read [Build a Plugin](/extend/build-a-plugin/) for the trusted `tools(ctx)` and `heartbeat(ctx)` APIs that the scheduler uses.
diff --git a/packages/docs/src/content/docs/reference/api/functions/createApp.md b/packages/docs/src/content/docs/reference/api/functions/createApp.md
index 83d9de613..0e0f9f689 100644
--- a/packages/docs/src/content/docs/reference/api/functions/createApp.md
+++ b/packages/docs/src/content/docs/reference/api/functions/createApp.md
@@ -7,7 +7,7 @@ title: "createApp"
 
 > **createApp**(`options?`): `Promise`\<`Hono`\<`BlankEnv`, `BlankSchema`, `"/"`\>\>
 
-Defined in: [app.ts:180](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L180)
+Defined in: [app.ts:179](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L179)
 
 Create a Hono app with all Junior routes.
 
diff --git a/packages/docs/src/content/docs/reference/api/interfaces/JuniorAppOptions.md b/packages/docs/src/content/docs/reference/api/interfaces/JuniorAppOptions.md
index e80efdc11..73f513fae 100644
--- a/packages/docs/src/content/docs/reference/api/interfaces/JuniorAppOptions.md
+++ b/packages/docs/src/content/docs/reference/api/interfaces/JuniorAppOptions.md
@@ -5,7 +5,7 @@ prev: false
 title: "JuniorAppOptions"
 ---
 
-Defined in: [app.ts:33](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L33)
+Defined in: [app.ts:32](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L32)
 
 ## Properties
 
@@ -13,7 +13,7 @@ Defined in: [app.ts:33](https://github.com/getsentry/junior/blob/main/packages/j
 
 > `optional` **configDefaults?**: `Record`\<`string`, `unknown`\>
 
-Defined in: [app.ts:35](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L35)
+Defined in: [app.ts:34](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L34)
 
 Install-wide provider defaults (`provider.key` format). Channel overrides take precedence.
 
@@ -23,7 +23,7 @@ Install-wide provider defaults (`provider.key` format). Channel overrides take p
 
 > `optional` **plugins?**: `PluginConfig` \| `JuniorPlugin`[]
 
-Defined in: [app.ts:43](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L43)
+Defined in: [app.ts:42](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L42)
 
 Plugin packages/overrides, or trusted plugin instances loaded by this app.
 
@@ -37,4 +37,4 @@ their package config is merged with the catalog bundled by `juniorNitro()`.
 
 > `optional` **waitUntil?**: `WaitUntilFn`
 
-Defined in: [app.ts:44](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L44)
+Defined in: [app.ts:43](https://github.com/getsentry/junior/blob/main/packages/junior/src/app.ts#L43)
diff --git a/packages/docs/src/content/docs/reference/config-and-env.md b/packages/docs/src/content/docs/reference/config-and-env.md
index e3e03ccbc..ba4d5b33d 100644
--- a/packages/docs/src/content/docs/reference/config-and-env.md
+++ b/packages/docs/src/content/docs/reference/config-and-env.md
@@ -25,8 +25,8 @@ related:
 | `AI_WEB_SEARCH_MODEL`                       | No          | Override for the `webSearch` tool model. Defaults to a search-tuned model; does not fall through to `AI_MODEL`.                                       |
 | `JUNIOR_BASE_URL`                           | No          | Canonical base URL for callback/auth URL generation.                                                                                                  |
 | `JUNIOR_STATE_KEY_PREFIX`                   | No          | Optional namespace prepended to all state-adapter keys, locks, and queues. Use separate prefixes when sharing one Redis database across environments. |
-| `CRON_SECRET` or `JUNIOR_SCHEDULER_SECRET`  | Conditional | Bearer token for internal scheduler and heartbeat routes; use `CRON_SECRET` with Vercel Cron, or `JUNIOR_SCHEDULER_SECRET` for an external scheduler. |
-| `JUNIOR_TIMEZONE`                           | No          | Default IANA timezone for scheduler authoring and other timezone-sensitive behavior. Defaults to `America/Los_Angeles`.                               |
+| `CRON_SECRET` or `JUNIOR_SCHEDULER_SECRET`  | Conditional | Bearer token for the internal heartbeat route; use `CRON_SECRET` with Vercel Cron, or `JUNIOR_SCHEDULER_SECRET` for a non-Vercel heartbeat caller.    |
+| `JUNIOR_TIMEZONE`                           | No          | Default IANA timezone for scheduler authoring when the scheduler plugin is enabled. Defaults to `America/Los_Angeles`.                                |
 | `AI_GATEWAY_API_KEY`                        | No          | AI gateway auth if used in your setup.                                                                                                                |
 
 Generate `JUNIOR_SECRET` with Node, then store the generated value in every environment that runs the same app:
diff --git a/packages/docs/src/content/docs/start-here/deploy-to-vercel.md b/packages/docs/src/content/docs/start-here/deploy-to-vercel.md
index 01de8d64b..c9835d655 100644
--- a/packages/docs/src/content/docs/start-here/deploy-to-vercel.md
+++ b/packages/docs/src/content/docs/start-here/deploy-to-vercel.md
@@ -43,7 +43,7 @@ Keep the Vercel build command as `pnpm build`. `junior snapshot create` prepares
 
 ## Enable the heartbeat cron
 
-Junior uses a one-minute internal heartbeat to run scheduled tasks and recover stale agent dispatches. The scaffolded `vercel.json` should include this cron:
+Junior uses a one-minute internal heartbeat to run trusted plugin heartbeats and recover stale agent dispatches. The scheduler plugin uses this heartbeat when scheduled tasks are enabled. The scaffolded `vercel.json` should include this cron:
 
 ```json title="vercel.json"
 {
diff --git a/packages/docs/src/content/docs/start-here/existing-app.md b/packages/docs/src/content/docs/start-here/existing-app.md
index 1f7937993..d47a0b28a 100644
--- a/packages/docs/src/content/docs/start-here/existing-app.md
+++ b/packages/docs/src/content/docs/start-here/existing-app.md
@@ -58,6 +58,7 @@ If your existing app already owns routes, make sure the Junior Hono app still re
 
 Some packages also export trusted runtime hooks. Register those in `createApp()`;
 do not rely on `juniorNitro()` alone. For example, see
+[Scheduler Plugin](/extend/scheduler-plugin/) for scheduled tasks and
 [GitHub Plugin](/extend/github-plugin/) for the `githubPlugin()` app-code setup.
 
 ## Add app files
diff --git a/packages/docs/src/content/docs/start-here/quickstart.md b/packages/docs/src/content/docs/start-here/quickstart.md
index 1401e4431..858ddf120 100644
--- a/packages/docs/src/content/docs/start-here/quickstart.md
+++ b/packages/docs/src/content/docs/start-here/quickstart.md
@@ -100,7 +100,7 @@ Packaged plugins must be installed and listed in `juniorNitro` so Nitro bundles
 Install only the plugins you plan to enable:
 
 ```bash
-pnpm add @sentry/junior-agent-browser @sentry/junior-datadog @sentry/junior-github @sentry/junior-hex @sentry/junior-linear @sentry/junior-notion @sentry/junior-sentry
+pnpm add @sentry/junior-agent-browser @sentry/junior-datadog @sentry/junior-github @sentry/junior-hex @sentry/junior-linear @sentry/junior-notion @sentry/junior-scheduler @sentry/junior-sentry
 ```
 
 Then list them in `nitro.config.ts`:
@@ -121,6 +121,7 @@ export default defineConfig({
           "@sentry/junior-hex",
           "@sentry/junior-linear",
           "@sentry/junior-notion",
+          "@sentry/junior-scheduler",
           "@sentry/junior-sentry",
         ],
       },
@@ -139,9 +140,11 @@ pnpm check
 ```
 
 Plugins with trusted runtime hooks need one more app-code registration step.
-For example, `@sentry/junior-github` must be registered with `githubPlugin()`
-inside `createApp()` to enforce Git commit attribution. See
-[GitHub Plugin](/extend/github-plugin/) for that setup.
+For example, `@sentry/junior-scheduler` must be registered with
+`schedulerPlugin()` inside `createApp()` to enable scheduled tasks, and
+`@sentry/junior-github` must be registered with `githubPlugin()` to enforce Git
+commit attribution. See [Scheduler Plugin](/extend/scheduler-plugin/) and
+[GitHub Plugin](/extend/github-plugin/) for those setups.
 
 ## Verify plugin content
 
diff --git a/packages/junior-evals/evals/behavior-harness.ts b/packages/junior-evals/evals/behavior-harness.ts
index 2b5c903eb..7eeda99bd 100644
--- a/packages/junior-evals/evals/behavior-harness.ts
+++ b/packages/junior-evals/evals/behavior-harness.ts
@@ -33,7 +33,7 @@ import {
 import { getAgentPlugins, setAgentPlugins } from "@/chat/plugins/agent-hooks";
 import { getPluginOAuthConfig, setPluginConfig } from "@/chat/plugins/registry";
 import { generateAssistantReply } from "@/chat/respond";
-import { createSchedulerPlugin } from "@/chat/scheduler/plugin";
+import { schedulerPlugin } from "@sentry/junior-scheduler";
 import { getStateAdapter } from "@/chat/state/adapter";
 import { resetSkillDiscoveryCache } from "@/chat/skills";
 import { createWebFetchTool } from "@/chat/tools/web/fetch-tool";
@@ -1679,7 +1679,7 @@ export async function runEvalScenario(
   try {
     const currentAgentPlugins = getAgentPlugins();
     previousAgentPlugins = setAgentPlugins([
-      createSchedulerPlugin(),
+      schedulerPlugin(),
       ...currentAgentPlugins.filter((plugin) => plugin.name !== "scheduler"),
     ]);
 
diff --git a/packages/junior-evals/package.json b/packages/junior-evals/package.json
index 8d6a551c1..7bbc0d629 100644
--- a/packages/junior-evals/package.json
+++ b/packages/junior-evals/package.json
@@ -12,6 +12,7 @@
   "devDependencies": {
     "@sentry/junior": "workspace:*",
     "@sentry/junior-github": "workspace:*",
+    "@sentry/junior-scheduler": "workspace:*",
     "@sentry/junior-sentry": "workspace:*",
     "@sentry/junior-testing": "workspace:*",
     "chat": "4.29.0",
diff --git a/packages/junior-plugin-api/src/index.ts b/packages/junior-plugin-api/src/index.ts
index a820e9c02..88578c8a6 100644
--- a/packages/junior-plugin-api/src/index.ts
+++ b/packages/junior-plugin-api/src/index.ts
@@ -25,6 +25,14 @@ export interface AgentPluginLogger {
   warn(message: string, metadata?: Record<string, unknown>): void;
 }
 
+/** Thrown when a trusted plugin tool rejects invalid model or user input. */
+export class AgentPluginToolInputError extends Error {
+  constructor(message: string, options?: { cause?: unknown }) {
+    super(message, options);
+    this.name = "AgentPluginToolInputError";
+  }
+}
+
 export interface AgentPluginContext {
   log: AgentPluginLogger;
   plugin: AgentPluginMetadata;
@@ -138,6 +146,12 @@ export interface AgentPluginState {
   delete(key: string): Promise<void>;
   get<T = unknown>(key: string): Promise<T | undefined>;
   set(key: string, value: unknown, ttlMs?: number): Promise<void>;
+  setIfNotExists(key: string, value: unknown, ttlMs?: number): Promise<boolean>;
+  withLock<T>(
+    key: string,
+    ttlMs: number,
+    callback: () => Promise<T>,
+  ): Promise<T>;
 }
 
 export interface HeartbeatHookContext extends AgentPluginContext {
@@ -165,6 +179,7 @@ export interface AgentPluginHooks {
 }
 
 export interface JuniorPluginConfig {
+  legacyStatePrefixes?: string[];
   packages?: string[];
 }
 
diff --git a/packages/junior-scheduler/package.json b/packages/junior-scheduler/package.json
new file mode 100644
index 000000000..b2d91d2e2
--- /dev/null
+++ b/packages/junior-scheduler/package.json
@@ -0,0 +1,40 @@
+{
+  "name": "@sentry/junior-scheduler",
+  "version": "0.55.0",
+  "private": false,
+  "publishConfig": {
+    "access": "public"
+  },
+  "type": "module",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/getsentry/junior.git",
+    "directory": "packages/junior-scheduler"
+  },
+  "exports": {
+    ".": {
+      "types": "./src/index.ts",
+      "default": "./dist/index.js"
+    }
+  },
+  "files": [
+    "dist",
+    "src",
+    "plugin.yaml"
+  ],
+  "scripts": {
+    "build": "tsup && tsc -p tsconfig.build.json --emitDeclarationOnly",
+    "prepare": "pnpm run build",
+    "prepack": "pnpm run build",
+    "typecheck": "tsc --noEmit"
+  },
+  "dependencies": {
+    "@sentry/junior-plugin-api": "workspace:*",
+    "@sinclair/typebox": "^0.34.49"
+  },
+  "devDependencies": {
+    "@types/node": "^25.9.1",
+    "tsup": "^8.5.1",
+    "typescript": "^6.0.3"
+  }
+}
diff --git a/packages/junior-scheduler/plugin.yaml b/packages/junior-scheduler/plugin.yaml
new file mode 100644
index 000000000..9192075d9
--- /dev/null
+++ b/packages/junior-scheduler/plugin.yaml
@@ -0,0 +1,2 @@
+name: scheduler
+description: Scheduled Junior task management and heartbeat dispatch
diff --git a/packages/junior/src/chat/scheduler/cadence.ts b/packages/junior-scheduler/src/cadence.ts
similarity index 99%
rename from packages/junior/src/chat/scheduler/cadence.ts
rename to packages/junior-scheduler/src/cadence.ts
index 6b70455cf..8077690a9 100644
--- a/packages/junior/src/chat/scheduler/cadence.ts
+++ b/packages/junior-scheduler/src/cadence.ts
@@ -3,7 +3,7 @@ import type {
   ScheduledLocalTime,
   ScheduledTask,
   ScheduledTaskRecurrence,
-} from "@/chat/scheduler/types";
+} from "./types";
 
 /** Parse an ISO timestamp into a finite Unix timestamp in milliseconds. */
 export function parseScheduleTimestamp(value: string): number | undefined {
diff --git a/packages/junior-scheduler/src/index.ts b/packages/junior-scheduler/src/index.ts
new file mode 100644
index 000000000..96b12b50c
--- /dev/null
+++ b/packages/junior-scheduler/src/index.ts
@@ -0,0 +1,27 @@
+export { createSchedulerPlugin, schedulerPlugin } from "./plugin";
+export { buildScheduledTaskRunPrompt } from "./prompt";
+export {
+  createSlackScheduleCreateTaskTool,
+  createSlackScheduleDeleteTaskTool,
+  createSlackScheduleListTasksTool,
+  createSlackScheduleRunTaskNowTool,
+  createSlackScheduleUpdateTaskTool,
+  type SchedulerToolContext,
+} from "./schedule-tools";
+export { createSchedulerStore } from "./store";
+export type {
+  ScheduledCalendarFrequency,
+  ScheduledLocalTime,
+  ScheduledRun,
+  ScheduledRunStatus,
+  ScheduledTask,
+  ScheduledTaskConversationAccess,
+  ScheduledTaskCredentialSubject,
+  ScheduledTaskDestination,
+  ScheduledTaskExecutionActor,
+  ScheduledTaskPrincipal,
+  ScheduledTaskRecurrence,
+  ScheduledTaskSchedule,
+  ScheduledTaskSpec,
+  ScheduledTaskStatus,
+} from "./types";
diff --git a/packages/junior/src/chat/scheduler/plugin.ts b/packages/junior-scheduler/src/plugin.ts
similarity index 90%
rename from packages/junior/src/chat/scheduler/plugin.ts
rename to packages/junior-scheduler/src/plugin.ts
index 44f402a6c..eecc31e6b 100644
--- a/packages/junior/src/chat/scheduler/plugin.ts
+++ b/packages/junior-scheduler/src/plugin.ts
@@ -1,23 +1,20 @@
 import {
   defineJuniorPlugin,
   type Dispatch,
+  type AgentPluginToolDefinition,
   type ToolRegistrationHookContext,
 } from "@sentry/junior-plugin-api";
-import { buildScheduledTaskRunPrompt } from "@/chat/scheduler/prompt";
-import {
-  createStateSchedulerStore,
-  type SchedulerStore,
-} from "@/chat/scheduler/store";
-import type { ScheduledRun, ScheduledTask } from "@/chat/scheduler/types";
+import { buildScheduledTaskRunPrompt } from "./prompt";
+import { createSchedulerStore, type SchedulerStore } from "./store";
+import type { ScheduledRun, ScheduledTask } from "./types";
 import {
   createSlackScheduleCreateTaskTool,
   createSlackScheduleDeleteTaskTool,
   createSlackScheduleListTasksTool,
   createSlackScheduleRunTaskNowTool,
   createSlackScheduleUpdateTaskTool,
-} from "@/chat/tools/slack/schedule-tools";
-import type { ToolDefinition } from "@/chat/tools/definition";
-import type { ToolRuntimeContext } from "@/chat/tools/types";
+  type SchedulerToolContext,
+} from "./schedule-tools";
 
 const SCHEDULER_HEARTBEAT_LIMIT = 10;
 
@@ -42,7 +39,7 @@ function shouldSkipRun(
 
 function createSchedulerToolContext(
   ctx: ToolRegistrationHookContext,
-): ToolRuntimeContext {
+): SchedulerToolContext {
   return {
     channelCapabilities: ctx.channelCapabilities ?? {
       canAddReactions: false,
@@ -52,7 +49,7 @@ function createSchedulerToolContext(
     channelId: ctx.channelId,
     messageTs: ctx.messageTs,
     requester: ctx.requester,
-    sandbox: {} as ToolRuntimeContext["sandbox"],
+    state: ctx.state,
     teamId: ctx.teamId,
     threadTs: ctx.threadTs,
     userText: ctx.userText,
@@ -63,7 +60,7 @@ async function applyDispatchResult(args: {
   dispatch: Dispatch;
   nowMs: number;
   run: ScheduledRun;
-  store: ReturnType<typeof createStateSchedulerStore>;
+  store: ReturnType<typeof createSchedulerStore>;
 }): Promise<boolean> {
   if (args.dispatch.status === "completed") {
     const completed = await args.store.markRunCompleted({
@@ -173,10 +170,14 @@ async function failClaimedRun(args: {
 export function createSchedulerPlugin() {
   return defineJuniorPlugin({
     name: "scheduler",
+    pluginConfig: {
+      legacyStatePrefixes: ["junior:scheduler"],
+      packages: ["@sentry/junior-scheduler"],
+    },
     hooks: {
       tools(ctx) {
         if (!ctx.channelId || !ctx.teamId || !ctx.requester?.userId) {
-          return {} as Record<string, ToolDefinition<any>>;
+          return {} as Record<string, AgentPluginToolDefinition<any>>;
         }
         const context = createSchedulerToolContext(ctx);
         return {
@@ -185,10 +186,10 @@ export function createSchedulerPlugin() {
           slackScheduleUpdateTask: createSlackScheduleUpdateTaskTool(context),
           slackScheduleDeleteTask: createSlackScheduleDeleteTaskTool(context),
           slackScheduleRunTaskNow: createSlackScheduleRunTaskNowTool(context),
-        } satisfies Record<string, ToolDefinition<any>>;
+        } satisfies Record<string, AgentPluginToolDefinition<any>>;
       },
       async heartbeat(ctx) {
-        const store = createStateSchedulerStore();
+        const store = createSchedulerStore(ctx.state);
         let processedCount = 0;
         let dispatchCount = 0;
         for (const run of await store.listIncompleteRuns()) {
@@ -306,3 +307,6 @@ export function createSchedulerPlugin() {
     },
   });
 }
+
+/** Register trusted scheduler runtime hooks for scheduled Junior tasks. */
+export const schedulerPlugin = createSchedulerPlugin;
diff --git a/packages/junior/src/chat/scheduler/prompt.ts b/packages/junior-scheduler/src/prompt.ts
similarity index 93%
rename from packages/junior/src/chat/scheduler/prompt.ts
rename to packages/junior-scheduler/src/prompt.ts
index 8b19b335a..a22092b99 100644
--- a/packages/junior/src/chat/scheduler/prompt.ts
+++ b/packages/junior-scheduler/src/prompt.ts
@@ -1,9 +1,17 @@
-import { escapeXml } from "@/chat/xml";
 import {
   SCHEDULED_TASK_SYSTEM_ACTOR,
   type ScheduledRun,
   type ScheduledTask,
-} from "@/chat/scheduler/types";
+} from "./types";
+
+function escapeXml(value: string): string {
+  return value
+    .replaceAll("&", "&amp;")
+    .replaceAll("<", "&lt;")
+    .replaceAll(">", "&gt;")
+    .replaceAll('"', "&quot;")
+    .replaceAll("'", "&apos;");
+}
 
 const EXECUTION_RULES = [
   "- Execute as the scheduled-task system actor; creator metadata is audit context, not an active user identity.",
diff --git a/packages/junior/src/chat/tools/slack/schedule-tools.ts b/packages/junior-scheduler/src/schedule-tools.ts
similarity index 87%
rename from packages/junior/src/chat/tools/slack/schedule-tools.ts
rename to packages/junior-scheduler/src/schedule-tools.ts
index ad207a191..e6db9b6fe 100644
--- a/packages/junior/src/chat/tools/slack/schedule-tools.ts
+++ b/packages/junior-scheduler/src/schedule-tools.ts
@@ -1,11 +1,14 @@
 import { randomUUID } from "node:crypto";
 import { Type } from "@sinclair/typebox";
 import {
-  buildCalendarRecurrence,
-  parseScheduleTimestamp,
-} from "@/chat/scheduler/cadence";
-import { createStateSchedulerStore } from "@/chat/scheduler/store";
-import { SCHEDULED_TASK_SYSTEM_ACTOR } from "@/chat/scheduler/types";
+  AgentPluginToolInputError,
+  type AgentPluginRequester,
+  type AgentPluginState,
+  type AgentPluginToolDefinition,
+} from "@sentry/junior-plugin-api";
+import { buildCalendarRecurrence, parseScheduleTimestamp } from "./cadence";
+import { createSchedulerStore } from "./store";
+import { SCHEDULED_TASK_SYSTEM_ACTOR } from "./types";
 import type {
   ScheduledCalendarFrequency,
   ScheduledTask,
@@ -15,12 +18,22 @@ import type {
   ScheduledTaskPrincipal,
   ScheduledTaskRecurrence,
   ScheduledTaskStatus,
-} from "@/chat/scheduler/types";
-import { isDmChannel, normalizeSlackConversationId } from "@/chat/slack/client";
-import { isSlackTeamId } from "@/chat/slack/ids";
-import { tool } from "@/chat/tools/definition";
-import { ToolInputError } from "@/chat/tools/execution/tool-input-error";
-import type { ToolRuntimeContext } from "@/chat/tools/types";
+} from "./types";
+
+export interface SchedulerToolContext {
+  channelCapabilities: {
+    canAddReactions: boolean;
+    canCreateCanvas: boolean;
+    canPostToChannel: boolean;
+  };
+  channelId?: string;
+  messageTs?: string;
+  requester?: AgentPluginRequester;
+  state: AgentPluginState;
+  teamId?: string;
+  threadTs?: string;
+  userText?: string;
+}
 
 const TASK_ID_PREFIX = "sched";
 const MAX_LISTED_TASKS = 50;
@@ -40,11 +53,11 @@ const recurrenceInputSchema = Type.Union([
 ]);
 
 function throwToolInputError(error: string): never {
-  throw new ToolInputError(error);
+  throw new AgentPluginToolInputError(error);
 }
 
 function requireActiveDestination(
-  context: ToolRuntimeContext,
+  context: SchedulerToolContext,
 ): ScheduledTaskDestination {
   const channelId = normalizeSlackConversationId(context.channelId);
   if (!channelId) {
@@ -64,7 +77,9 @@ function requireActiveDestination(
   };
 }
 
-function requireRequester(context: ToolRuntimeContext): ScheduledTaskPrincipal {
+function requireRequester(
+  context: SchedulerToolContext,
+): ScheduledTaskPrincipal {
   const userId = context.requester?.userId;
   if (!userId) {
     throwToolInputError("No active Slack requester context is available.");
@@ -81,6 +96,32 @@ function requireRequester(context: ToolRuntimeContext): ScheduledTaskPrincipal {
   };
 }
 
+function tool<TInput = any>(
+  definition: AgentPluginToolDefinition<TInput>,
+): AgentPluginToolDefinition<TInput> {
+  return definition;
+}
+
+function normalizeSlackConversationId(
+  value: string | undefined,
+): string | undefined {
+  if (!value) return undefined;
+  const trimmed = value.trim();
+  if (!trimmed) return undefined;
+  if (!trimmed.startsWith("slack:")) return trimmed;
+
+  const parts = trimmed.split(":");
+  return parts[1]?.trim() || undefined;
+}
+
+function isDmChannel(channelId: string): boolean {
+  return normalizeSlackConversationId(channelId)?.startsWith("D") ?? false;
+}
+
+function isSlackTeamId(value: string): boolean {
+  return /^T[A-Z0-9]+$/.test(value);
+}
+
 function getConversationAccess(
   destination: ScheduledTaskDestination,
 ): ScheduledTaskConversationAccess {
@@ -125,12 +166,14 @@ function sameDestination(
 }
 
 async function getWritableTask(args: {
-  context: ToolRuntimeContext;
+  context: SchedulerToolContext;
   taskId: string;
 }): Promise<ScheduledTask> {
   const destination = requireActiveDestination(args.context);
 
-  const task = await createStateSchedulerStore().getTask(args.taskId);
+  const task = await createSchedulerStore(args.context.state).getTask(
+    args.taskId,
+  );
   if (!task || task.status === "deleted") {
     throwToolInputError(
       "Scheduled task was not found in the active destination.",
@@ -301,7 +344,9 @@ function parseNextRunAtMs(
 }
 
 /** Create a tool that stores a scheduled task for the active Slack context. */
-export function createSlackScheduleCreateTaskTool(context: ToolRuntimeContext) {
+export function createSlackScheduleCreateTaskTool(
+  context: SchedulerToolContext,
+) {
   return tool({
     description:
       "Create a scheduled Junior task in the active Slack conversation.",
@@ -378,7 +423,7 @@ export function createSlackScheduleCreateTaskTool(context: ToolRuntimeContext) {
         version: 1,
       };
 
-      await createStateSchedulerStore().saveTask(task);
+      await createSchedulerStore(context.state).saveTask(task);
       return {
         ok: true,
         task: compactTask(task),
@@ -388,7 +433,9 @@ export function createSlackScheduleCreateTaskTool(context: ToolRuntimeContext) {
 }
 
 /** Create a tool that lists scheduled tasks for the active Slack destination. */
-export function createSlackScheduleListTasksTool(context: ToolRuntimeContext) {
+export function createSlackScheduleListTasksTool(
+  context: SchedulerToolContext,
+) {
   return tool({
     description:
       "List scheduled Junior tasks for the active Slack conversation.",
@@ -402,7 +449,7 @@ export function createSlackScheduleListTasksTool(context: ToolRuntimeContext) {
     execute: async () => {
       const destination = requireActiveDestination(context);
 
-      const tasks = await createStateSchedulerStore().listTasksForTeam(
+      const tasks = await createSchedulerStore(context.state).listTasksForTeam(
         destination.teamId,
       );
       const matching = tasks.filter((task) =>
@@ -420,7 +467,9 @@ export function createSlackScheduleListTasksTool(context: ToolRuntimeContext) {
 }
 
 /** Create a tool that edits a scheduled task in the active Slack destination. */
-export function createSlackScheduleUpdateTaskTool(context: ToolRuntimeContext) {
+export function createSlackScheduleUpdateTaskTool(
+  context: SchedulerToolContext,
+) {
   return tool({
     description: "Edit, pause, resume, or reschedule a Junior scheduled task.",
     promptSnippet: "edit/pause/resume one schedule in this Slack destination",
@@ -507,7 +556,7 @@ export function createSlackScheduleUpdateTaskTool(context: ToolRuntimeContext) {
         version: lookup.version + 1,
       };
 
-      await createStateSchedulerStore().saveTask(next);
+      await createSchedulerStore(context.state).saveTask(next);
       return {
         ok: true,
         task: compactTask(next),
@@ -517,7 +566,9 @@ export function createSlackScheduleUpdateTaskTool(context: ToolRuntimeContext) {
 }
 
 /** Create a tool that removes a scheduled task from the active Slack destination. */
-export function createSlackScheduleDeleteTaskTool(context: ToolRuntimeContext) {
+export function createSlackScheduleDeleteTaskTool(
+  context: SchedulerToolContext,
+) {
   return tool({
     description:
       "Delete a Junior scheduled task from the active Slack conversation.",
@@ -538,7 +589,7 @@ export function createSlackScheduleDeleteTaskTool(context: ToolRuntimeContext) {
         version: lookup.version + 1,
       };
 
-      await createStateSchedulerStore().saveTask(next);
+      await createSchedulerStore(context.state).saveTask(next);
       return {
         ok: true,
         task: compactTask(next),
@@ -548,7 +599,9 @@ export function createSlackScheduleDeleteTaskTool(context: ToolRuntimeContext) {
 }
 
 /** Create a tool that marks an existing scheduled task due immediately. */
-export function createSlackScheduleRunTaskNowTool(context: ToolRuntimeContext) {
+export function createSlackScheduleRunTaskNowTool(
+  context: SchedulerToolContext,
+) {
   return tool({
     description:
       "Queue an active Junior scheduled task to run as soon as possible.",
@@ -577,7 +630,7 @@ export function createSlackScheduleRunTaskNowTool(context: ToolRuntimeContext) {
         version: lookup.version + 1,
       };
 
-      await createStateSchedulerStore().saveTask(next);
+      await createSchedulerStore(context.state).saveTask(next);
       return {
         ok: true,
         task: compactTask(next),
diff --git a/packages/junior/src/chat/scheduler/store.ts b/packages/junior-scheduler/src/store.ts
similarity index 94%
rename from packages/junior/src/chat/scheduler/store.ts
rename to packages/junior-scheduler/src/store.ts
index 10cc9c06a..d792213fa 100644
--- a/packages/junior/src/chat/scheduler/store.ts
+++ b/packages/junior-scheduler/src/store.ts
@@ -1,7 +1,6 @@
-import type { Lock, StateAdapter } from "chat";
-import { getNextRunAtMs } from "@/chat/scheduler/cadence";
-import { getStateAdapter } from "@/chat/state/adapter";
-import type { ScheduledRun, ScheduledTask } from "@/chat/scheduler/types";
+import type { AgentPluginState } from "@sentry/junior-plugin-api";
+import { getNextRunAtMs } from "./cadence";
+import type { ScheduledRun, ScheduledTask } from "./types";
 
 const SCHEDULER_KEY_PREFIX = "junior:scheduler";
 const SCHEDULER_RECORD_TTL_MS = 5 * 365 * 24 * 60 * 60 * 1000;
@@ -96,24 +95,15 @@ function unique(values: string[]): string[] {
 }
 
 async function withLock<T>(
-  state: StateAdapter,
+  state: AgentPluginState,
   key: string,
   callback: () => Promise<T>,
 ): Promise<T> {
-  const lock: Lock | null = await state.acquireLock(key, LOCK_TTL_MS);
-  if (!lock) {
-    throw new Error(`Could not acquire scheduler lock for ${key}`);
-  }
-
-  try {
-    return await callback();
-  } finally {
-    await state.releaseLock(lock);
-  }
+  return await state.withLock(key, LOCK_TTL_MS, callback);
 }
 
 async function addToIndex(
-  state: StateAdapter,
+  state: AgentPluginState,
   key: string,
   taskId: string,
 ): Promise<void> {
@@ -126,7 +116,7 @@ async function addToIndex(
 }
 
 async function removeFromIndex(
-  state: StateAdapter,
+  state: AgentPluginState,
   key: string,
   taskId: string,
 ): Promise<void> {
@@ -148,7 +138,10 @@ async function removeFromIndex(
   });
 }
 
-async function getIndex(state: StateAdapter, key: string): Promise<string[]> {
+async function getIndex(
+  state: AgentPluginState,
+  key: string,
+): Promise<string[]> {
   const values = (await state.get<string[]>(key)) ?? [];
   return unique(
     values.filter((value): value is string => typeof value === "string"),
@@ -156,7 +149,7 @@ async function getIndex(state: StateAdapter, key: string): Promise<string[]> {
 }
 
 async function clearActiveRun(
-  state: StateAdapter,
+  state: AgentPluginState,
   taskId: string,
   runId: string,
 ): Promise<void> {
@@ -169,7 +162,7 @@ async function clearActiveRun(
 }
 
 async function clearStaleActiveRun(
-  state: StateAdapter,
+  state: AgentPluginState,
   taskId: string,
   nowMs: number,
 ): Promise<boolean> {
@@ -353,15 +346,14 @@ function canFinishRun(
   return run.status === "running" && run.startedAtMs === startedAtMs;
 }
 
-class StateAdapterSchedulerStore implements SchedulerStore {
-  private readonly state: StateAdapter;
+class PluginStateSchedulerStore implements SchedulerStore {
+  private readonly state: AgentPluginState;
 
-  constructor(state: StateAdapter) {
+  constructor(state: AgentPluginState) {
     this.state = state;
   }
 
   async saveTask(task: ScheduledTask): Promise<void> {
-    await this.state.connect();
     await withLock(this.state, taskLockKey(task.id), async () => {
       const current =
         (await this.state.get<ScheduledTask>(taskKey(task.id))) ?? undefined;
@@ -416,12 +408,10 @@ class StateAdapterSchedulerStore implements SchedulerStore {
   }
 
   async getTask(taskId: string): Promise<ScheduledTask | undefined> {
-    await this.state.connect();
     return (await this.state.get<ScheduledTask>(taskKey(taskId))) ?? undefined;
   }
 
   async listTasksForTeam(teamId: string): Promise<ScheduledTask[]> {
-    await this.state.connect();
     const ids = await getIndex(this.state, teamTaskIndexKey(teamId));
     const tasks = await Promise.all(ids.map((id) => this.getTask(id)));
     return tasks
@@ -433,7 +423,6 @@ class StateAdapterSchedulerStore implements SchedulerStore {
   async claimDueRun(args: {
     nowMs: number;
   }): Promise<ScheduledRun | undefined> {
-    await this.state.connect();
     const ids = await getIndex(this.state, globalTaskIndexKey());
 
     for (const id of ids) {
@@ -587,12 +576,10 @@ class StateAdapterSchedulerStore implements SchedulerStore {
   }
 
   async getRun(runId: string): Promise<ScheduledRun | undefined> {
-    await this.state.connect();
     return (await this.state.get<ScheduledRun>(runKey(runId))) ?? undefined;
   }
 
   async listIncompleteRuns(): Promise<ScheduledRun[]> {
-    await this.state.connect();
     const ids = await getIndex(this.state, globalTaskIndexKey());
     const runs: ScheduledRun[] = [];
     for (const taskId of ids) {
@@ -721,7 +708,6 @@ class StateAdapterSchedulerStore implements SchedulerStore {
     run: ScheduledRun;
     status: "blocked" | "completed" | "failed";
   }): Promise<void> {
-    await this.state.connect();
     await withLock(this.state, taskLockKey(args.run.taskId), async () => {
       const current =
         (await this.state.get<ScheduledTask>(taskKey(args.run.taskId))) ??
@@ -812,7 +798,6 @@ class StateAdapterSchedulerStore implements SchedulerStore {
     runId: string,
     update: (run: ScheduledRun) => ScheduledRun | undefined,
   ): Promise<ScheduledRun | undefined> {
-    await this.state.connect();
     return await withLock(this.state, indexLockKey(runKey(runId)), async () => {
       const current = await this.getRun(runId);
       if (!current) {
@@ -828,9 +813,7 @@ class StateAdapterSchedulerStore implements SchedulerStore {
   }
 }
 
-/** Create the production scheduler store backed by Junior's state adapter. */
-export function createStateSchedulerStore(
-  stateAdapter: StateAdapter = getStateAdapter(),
-): SchedulerStore {
-  return new StateAdapterSchedulerStore(stateAdapter);
+/** Create a scheduler store backed by this plugin's durable state namespace. */
+export function createSchedulerStore(state: AgentPluginState): SchedulerStore {
+  return new PluginStateSchedulerStore(state);
 }
diff --git a/packages/junior/src/chat/scheduler/types.ts b/packages/junior-scheduler/src/types.ts
similarity index 100%
rename from packages/junior/src/chat/scheduler/types.ts
rename to packages/junior-scheduler/src/types.ts
diff --git a/packages/junior-scheduler/tsconfig.build.json b/packages/junior-scheduler/tsconfig.build.json
new file mode 100644
index 000000000..b398e67a8
--- /dev/null
+++ b/packages/junior-scheduler/tsconfig.build.json
@@ -0,0 +1,10 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "declaration": true,
+    "incremental": false,
+    "noEmit": false,
+    "outDir": "dist",
+    "rootDir": "src"
+  }
+}
diff --git a/packages/junior-scheduler/tsconfig.json b/packages/junior-scheduler/tsconfig.json
new file mode 100644
index 000000000..8c5ea2850
--- /dev/null
+++ b/packages/junior-scheduler/tsconfig.json
@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "lib": ["ES2022"],
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+    "strict": true,
+    "skipLibCheck": true,
+    "isolatedModules": true,
+    "noEmit": true,
+    "types": ["node"]
+  },
+  "include": ["src/**/*.ts"]
+}
diff --git a/packages/junior-scheduler/tsup.config.ts b/packages/junior-scheduler/tsup.config.ts
new file mode 100644
index 000000000..a19165e0f
--- /dev/null
+++ b/packages/junior-scheduler/tsup.config.ts
@@ -0,0 +1,13 @@
+import { defineConfig } from "tsup";
+
+export default defineConfig({
+  entry: {
+    index: "src/index.ts",
+  },
+  format: "esm",
+  tsconfig: "tsconfig.build.json",
+  dts: false,
+  outDir: "dist",
+  clean: true,
+  external: ["@sentry/junior-plugin-api", "@sinclair/typebox"],
+});
diff --git a/packages/junior/package.json b/packages/junior/package.json
index 11758211c..6e9956e2d 100644
--- a/packages/junior/package.json
+++ b/packages/junior/package.json
@@ -66,6 +66,7 @@
     "@sentry/node": ">=10.0.0"
   },
   "devDependencies": {
+    "@sentry/junior-scheduler": "workspace:*",
     "@sentry/node": "10.53.1",
     "@types/node": "^25.9.1",
     "dependency-cruiser": "^17.4.0",
diff --git a/packages/junior/src/app.ts b/packages/junior/src/app.ts
index 6074ceef5..088824e2c 100644
--- a/packages/junior/src/app.ts
+++ b/packages/junior/src/app.ts
@@ -12,7 +12,6 @@ import {
   setAgentPlugins,
   validateAgentPlugins,
 } from "@/chat/plugins/agent-hooks";
-import { createSchedulerPlugin } from "@/chat/scheduler/plugin";
 import type { PluginConfig } from "@/chat/plugins/types";
 import type { JuniorPlugin } from "@sentry/junior-plugin-api";
 import { GET as diagnosticsGET } from "@/handlers/diagnostics";
@@ -179,10 +178,9 @@ function pluginConfigFromAgentPlugins(
 /** Create a Hono app with all Junior routes. */
 export async function createApp(options?: JuniorAppOptions): Promise<Hono> {
   const configuredPlugins = options?.plugins;
-  const agentPlugins = [
-    createSchedulerPlugin(),
-    ...(isJuniorPluginArray(configuredPlugins) ? configuredPlugins : []),
-  ];
+  const agentPlugins = isJuniorPluginArray(configuredPlugins)
+    ? configuredPlugins
+    : [];
   const pluginConfig = isJuniorPluginArray(configuredPlugins)
     ? mergePluginConfig(
         await resolveVirtualPluginConfig(),
diff --git a/packages/junior/src/chat/agent-dispatch/context.ts b/packages/junior/src/chat/agent-dispatch/context.ts
index 68c4a47df..b9fab7a08 100644
--- a/packages/junior/src/chat/agent-dispatch/context.ts
+++ b/packages/junior/src/chat/agent-dispatch/context.ts
@@ -28,6 +28,7 @@ function shouldScheduleDispatch(
 
 /** Build the plugin-scoped heartbeat context that gates durable dispatch access. */
 export function createHeartbeatContext(args: {
+  legacyStatePrefixes?: string[];
   nowMs: number;
   plugin: string;
 }): HeartbeatHookContext {
@@ -35,7 +36,9 @@ export function createHeartbeatContext(args: {
   return {
     plugin: { name: args.plugin },
     nowMs: args.nowMs,
-    state: createPluginState(args.plugin),
+    state: createPluginState(args.plugin, {
+      legacyStatePrefixes: args.legacyStatePrefixes,
+    }),
     log: createAgentPluginLogger(args.plugin),
     agent: {
       async dispatch(options) {
diff --git a/packages/junior/src/chat/agent-dispatch/heartbeat.ts b/packages/junior/src/chat/agent-dispatch/heartbeat.ts
index cefb57bee..2f51c1fc9 100644
--- a/packages/junior/src/chat/agent-dispatch/heartbeat.ts
+++ b/packages/junior/src/chat/agent-dispatch/heartbeat.ts
@@ -158,6 +158,7 @@ export async function runTrustedPluginHeartbeats(args: {
         Promise.resolve(
           heartbeat(
             createHeartbeatContext({
+              legacyStatePrefixes: plugin.pluginConfig?.legacyStatePrefixes,
               plugin: plugin.name,
               nowMs: args.nowMs,
             }),
diff --git a/packages/junior/src/chat/plugins/agent-hooks.ts b/packages/junior/src/chat/plugins/agent-hooks.ts
index 36ef18598..4ae5a6ef1 100644
--- a/packages/junior/src/chat/plugins/agent-hooks.ts
+++ b/packages/junior/src/chat/plugins/agent-hooks.ts
@@ -41,6 +41,33 @@ let agentPlugins: JuniorPlugin[] = [];
 const AGENT_PLUGIN_NAME_RE = /^[a-z][a-z0-9-]*$/;
 const AGENT_PLUGIN_TOOL_NAME_RE = /^[a-z][A-Za-z0-9]*$/;
 
+function validateLegacyStatePrefixes(plugin: JuniorPlugin): void {
+  const prefixes = plugin.pluginConfig?.legacyStatePrefixes;
+  if (prefixes === undefined) {
+    return;
+  }
+  if (!Array.isArray(prefixes)) {
+    throw new Error(
+      `Trusted plugin "${plugin.name}" legacyStatePrefixes must be an array`,
+    );
+  }
+
+  const allowedPrefix = `junior:${plugin.name}`;
+  for (const rawPrefix of prefixes) {
+    const prefix = typeof rawPrefix === "string" ? rawPrefix.trim() : "";
+    if (!prefix) {
+      throw new Error(
+        `Trusted plugin "${plugin.name}" legacy state prefixes must be non-empty strings`,
+      );
+    }
+    if (prefix !== allowedPrefix && !prefix.startsWith(`${allowedPrefix}:`)) {
+      throw new Error(
+        `Trusted plugin "${plugin.name}" legacy state prefix "${prefix}" must stay under "${allowedPrefix}"`,
+      );
+    }
+  }
+}
+
 /** Validate trusted plugin identity before it can affect process-wide hooks. */
 export function validateAgentPlugins(plugins: JuniorPlugin[]): void {
   const seen = new Set<string>();
@@ -54,6 +81,7 @@ export function validateAgentPlugins(plugins: JuniorPlugin[]): void {
       throw new Error(`Duplicate trusted plugin name "${plugin.name}"`);
     }
     seen.add(plugin.name);
+    validateLegacyStatePrefixes(plugin);
   }
 }
 
@@ -93,7 +121,9 @@ export function getAgentPluginTools(
       messageTs: context.messageTs,
       threadTs: context.threadTs,
       userText: context.userText,
-      state: createPluginState(plugin.name),
+      state: createPluginState(plugin.name, {
+        legacyStatePrefixes: plugin.pluginConfig?.legacyStatePrefixes,
+      }),
     });
     for (const [name, tool] of Object.entries(pluginTools)) {
       if (!AGENT_PLUGIN_TOOL_NAME_RE.test(name)) {
diff --git a/packages/junior/src/chat/plugins/state.ts b/packages/junior/src/chat/plugins/state.ts
index f4c415f2b..55fe61a92 100644
--- a/packages/junior/src/chat/plugins/state.ts
+++ b/packages/junior/src/chat/plugins/state.ts
@@ -4,6 +4,10 @@ import { getStateAdapter } from "@/chat/state/adapter";
 
 const MAX_PLUGIN_STATE_KEY_LENGTH = 512;
 
+export interface PluginStateOptions {
+  legacyStatePrefixes?: string[];
+}
+
 function hashKeyPart(value: string): string {
   return createHash("sha256").update(value).digest("hex").slice(0, 32);
 }
@@ -21,20 +25,50 @@ function validatePluginStateKey(key: string): void {
   }
 }
 
+function legacyStateKey(
+  key: string,
+  options: PluginStateOptions | undefined,
+): string | undefined {
+  for (const prefix of options?.legacyStatePrefixes ?? []) {
+    const trimmed = prefix.trim();
+    if (!trimmed) {
+      continue;
+    }
+    if (key === trimmed || key.startsWith(`${trimmed}:`)) {
+      return key;
+    }
+  }
+  return undefined;
+}
+
 /** Create a durable state namespace scoped to one trusted plugin. */
-export function createPluginState(plugin: string): AgentPluginState {
+export function createPluginState(
+  plugin: string,
+  options?: PluginStateOptions,
+): AgentPluginState {
   return {
     async delete(key) {
       validatePluginStateKey(key);
       const state = getStateAdapter();
       await state.connect();
       await state.delete(pluginStateKey(plugin, key));
+      const legacyKey = legacyStateKey(key, options);
+      if (legacyKey) {
+        await state.delete(legacyKey);
+      }
     },
-    async get(key) {
+    async get<T = unknown>(key: string): Promise<T | undefined> {
       validatePluginStateKey(key);
       const state = getStateAdapter();
       await state.connect();
-      return (await state.get(pluginStateKey(plugin, key))) ?? undefined;
+      const value = await state.get<T>(pluginStateKey(plugin, key));
+      if (value !== null && value !== undefined) {
+        return value;
+      }
+      const legacyKey = legacyStateKey(key, options);
+      return legacyKey
+        ? ((await state.get<T>(legacyKey)) ?? undefined)
+        : undefined;
     },
     async set(key, value, ttlMs) {
       validatePluginStateKey(key);
@@ -42,5 +76,39 @@ export function createPluginState(plugin: string): AgentPluginState {
       await state.connect();
       await state.set(pluginStateKey(plugin, key), value, ttlMs);
     },
+    async setIfNotExists(key, value, ttlMs) {
+      validatePluginStateKey(key);
+      const state = getStateAdapter();
+      await state.connect();
+      const legacyKey = legacyStateKey(key, options);
+      if (legacyKey) {
+        const existing = await state.get(legacyKey);
+        if (existing !== null && existing !== undefined) {
+          return false;
+        }
+      }
+      return await state.setIfNotExists(
+        pluginStateKey(plugin, key),
+        value,
+        ttlMs,
+      );
+    },
+    async withLock(key, ttlMs, callback) {
+      validatePluginStateKey(key);
+      const state = getStateAdapter();
+      await state.connect();
+      const lockKey =
+        legacyStateKey(key, options) ?? pluginStateKey(plugin, key);
+      const lock = await state.acquireLock(lockKey, ttlMs);
+      if (!lock) {
+        throw new Error(`Could not acquire plugin state lock for ${key}`);
+      }
+
+      try {
+        return await callback();
+      } finally {
+        await state.releaseLock(lock);
+      }
+    },
   };
 }
diff --git a/packages/junior/src/chat/tools/execution/tool-error-handler.ts b/packages/junior/src/chat/tools/execution/tool-error-handler.ts
index 4ce1d2f22..45cc6ad52 100644
--- a/packages/junior/src/chat/tools/execution/tool-error-handler.ts
+++ b/packages/junior/src/chat/tools/execution/tool-error-handler.ts
@@ -5,16 +5,26 @@ import {
   setSpanAttributes,
   type LogContext,
 } from "@/chat/logging";
+import { AgentPluginToolInputError } from "@sentry/junior-plugin-api";
 import { GEN_AI_PROVIDER_NAME } from "@/chat/pi/client";
 import { getMcpAwareErrorMessage, McpToolError } from "@/chat/mcp/errors";
 import { PluginCredentialFailureError } from "@/chat/services/plugin-auth-orchestration";
 import { SlackActionError } from "@/chat/slack/client";
 import { ToolInputError } from "@/chat/tools/execution/tool-input-error";
 
+function isPluginToolInputError(error: unknown): boolean {
+  return (
+    error instanceof AgentPluginToolInputError ||
+    (error instanceof Error && error.name === "AgentPluginToolInputError")
+  );
+}
+
 /** Classify tool errors into stable observability types. */
 function getToolErrorType(error: unknown): string {
   if (error instanceof McpToolError) return "tool_error";
-  if (error instanceof ToolInputError) return "tool_input_error";
+  if (error instanceof ToolInputError || isPluginToolInputError(error)) {
+    return "tool_input_error";
+  }
   return error instanceof Error ? error.name : "tool_execution_error";
 }
 
@@ -90,7 +100,9 @@ export function handleToolExecutionError(
 
   // Expected tool failures (MCP errors, model input errors) are not Sentry exceptions.
   const isExpectedToolFailure =
-    error instanceof McpToolError || error instanceof ToolInputError;
+    error instanceof McpToolError ||
+    error instanceof ToolInputError ||
+    isPluginToolInputError(error);
   if (!isExpectedToolFailure) {
     logException(
       error,
diff --git a/packages/junior/tests/integration/heartbeat.test.ts b/packages/junior/tests/integration/heartbeat.test.ts
index f47e31dce..6686386e3 100644
--- a/packages/junior/tests/integration/heartbeat.test.ts
+++ b/packages/junior/tests/integration/heartbeat.test.ts
@@ -2,9 +2,12 @@ import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import { defineJuniorPlugin } from "@sentry/junior-plugin-api";
 import { createHeartbeatContext } from "@/chat/agent-dispatch/context";
 import { recoverStaleDispatches } from "@/chat/agent-dispatch/heartbeat";
-import { createSchedulerPlugin } from "@/chat/scheduler/plugin";
-import { createStateSchedulerStore } from "@/chat/scheduler/store";
-import type { ScheduledTask } from "@/chat/scheduler/types";
+import {
+  createSchedulerStore,
+  schedulerPlugin,
+  type ScheduledTask,
+} from "@sentry/junior-scheduler";
+import { createPluginState } from "@/chat/plugins/state";
 import {
   createOrGetDispatch,
   getDispatchRecord,
@@ -32,6 +35,10 @@ function collectWaitUntil(tasks: Promise<unknown>[]): WaitUntilFn {
   };
 }
 
+function schedulerStore() {
+  return createSchedulerStore(createPluginState("scheduler"));
+}
+
 function createTask(overrides: Partial<ScheduledTask> = {}): ScheduledTask {
   const nextRunAtMs = TEST_RUN_AT_MS;
   return {
@@ -202,6 +209,30 @@ describe("trusted plugin heartbeat", () => {
     await expect(second.state.get("1")).resolves.toBe("second");
   });
 
+  it("claims scheduled tasks from the scheduler legacy state namespace", async () => {
+    const task = createTask({ id: "sched_legacy" });
+    const state = getStateAdapter();
+    await state.connect();
+    await state.set("junior:scheduler:tasks", [task.id]);
+    await state.set("junior:scheduler:team:T123:tasks", [task.id]);
+    await state.set("junior:scheduler:task:sched_legacy", task);
+
+    const store = createSchedulerStore(
+      createPluginState("scheduler", {
+        legacyStatePrefixes: ["junior:scheduler"],
+      }),
+    );
+
+    await expect(store.listTasksForTeam("T123")).resolves.toMatchObject([
+      { id: task.id },
+    ]);
+    await expect(
+      store.claimDueRun({ nowMs: TEST_NOW_MS }),
+    ).resolves.toMatchObject({
+      taskId: task.id,
+    });
+  });
+
   it("bounds dispatch fanout from one heartbeat context", async () => {
     const fetchMock = vi.fn(async () => {
       return new Response("Accepted", { status: 202 });
@@ -398,8 +429,8 @@ describe("trusted plugin heartbeat", () => {
       return new Response("Accepted", { status: 202 });
     });
     global.fetch = fetchMock as typeof fetch;
-    setAgentPlugins([createSchedulerPlugin()]);
-    const store = createStateSchedulerStore();
+    setAgentPlugins([schedulerPlugin()]);
+    const store = schedulerStore();
     await store.saveTask(createTask());
 
     const firstWaitUntilTasks: Promise<unknown>[] = [];
@@ -458,8 +489,8 @@ describe("trusted plugin heartbeat", () => {
       return new Response("Accepted", { status: 202 });
     });
     global.fetch = fetchMock as typeof fetch;
-    setAgentPlugins([createSchedulerPlugin()]);
-    const store = createStateSchedulerStore();
+    setAgentPlugins([schedulerPlugin()]);
+    const store = schedulerStore();
     await store.saveTask(
       createTask({
         destination: {
@@ -503,8 +534,8 @@ describe("trusted plugin heartbeat", () => {
       return new Response("Accepted", { status: 202 });
     });
     global.fetch = fetchMock as typeof fetch;
-    setAgentPlugins([createSchedulerPlugin()]);
-    const store = createStateSchedulerStore();
+    setAgentPlugins([schedulerPlugin()]);
+    const store = schedulerStore();
     await store.saveTask(createTask());
 
     const firstWaitUntilTasks: Promise<unknown>[] = [];
@@ -550,8 +581,8 @@ describe("trusted plugin heartbeat", () => {
       return new Response("Accepted", { status: 202 });
     });
     global.fetch = fetchMock as typeof fetch;
-    setAgentPlugins([createSchedulerPlugin()]);
-    const store = createStateSchedulerStore();
+    setAgentPlugins([schedulerPlugin()]);
+    const store = schedulerStore();
     await store.saveTask({
       ...createTask(),
       id: "sched_plugin_malformed",
@@ -594,8 +625,8 @@ describe("trusted plugin heartbeat", () => {
       return new Response("Accepted", { status: 202 });
     });
     global.fetch = fetchMock as typeof fetch;
-    setAgentPlugins([createSchedulerPlugin()]);
-    const store = createStateSchedulerStore();
+    setAgentPlugins([schedulerPlugin()]);
+    const store = schedulerStore();
     await store.saveTask({
       ...createTask(),
       id: "sched_plugin_bad_destination",
@@ -640,8 +671,8 @@ describe("trusted plugin heartbeat", () => {
       return new Response("Accepted", { status: 202 });
     });
     global.fetch = fetchMock as typeof fetch;
-    setAgentPlugins([createSchedulerPlugin()]);
-    const store = createStateSchedulerStore();
+    setAgentPlugins([schedulerPlugin()]);
+    const store = schedulerStore();
     const task = createDailyTask();
     await store.saveTask(task);
 
@@ -673,8 +704,8 @@ describe("trusted plugin heartbeat", () => {
       return new Response("Accepted", { status: 202 });
     });
     global.fetch = fetchMock as typeof fetch;
-    setAgentPlugins([createSchedulerPlugin()]);
-    const store = createStateSchedulerStore();
+    setAgentPlugins([schedulerPlugin()]);
+    const store = schedulerStore();
     const first = createDailyTask({
       id: "sched_plugin_duplicate_a",
       createdAtMs: Date.parse("2026-05-24T12:00:00.000Z"),
diff --git a/packages/junior/tests/integration/slack-schedule-tools.test.ts b/packages/junior/tests/integration/slack-schedule-tools.test.ts
index f69bba4f6..5ef74b929 100644
--- a/packages/junior/tests/integration/slack-schedule-tools.test.ts
+++ b/packages/junior/tests/integration/slack-schedule-tools.test.ts
@@ -1,15 +1,16 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
-import { disconnectStateAdapter, getStateAdapter } from "@/chat/state/adapter";
-import { createStateSchedulerStore } from "@/chat/scheduler/store";
-import { ToolInputError } from "@/chat/tools/execution/tool-input-error";
+import { AgentPluginToolInputError } from "@sentry/junior-plugin-api";
 import {
+  createSchedulerStore,
   createSlackScheduleCreateTaskTool,
   createSlackScheduleDeleteTaskTool,
   createSlackScheduleListTasksTool,
   createSlackScheduleRunTaskNowTool,
   createSlackScheduleUpdateTaskTool,
-} from "@/chat/tools/slack/schedule-tools";
-import type { ToolRuntimeContext } from "@/chat/tools/types";
+  type SchedulerToolContext,
+} from "@sentry/junior-scheduler";
+import { createPluginState } from "@/chat/plugins/state";
+import { disconnectStateAdapter } from "@/chat/state/adapter";
 
 vi.hoisted(() => {
   process.env.JUNIOR_STATE_ADAPTER = "memory";
@@ -18,8 +19,8 @@ vi.hoisted(() => {
 const TEST_TEAM_ID = `TSCHEDULE${Date.now()}`;
 
 function createContext(
-  overrides: Partial<ToolRuntimeContext> = {},
-): ToolRuntimeContext {
+  overrides: Partial<SchedulerToolContext> = {},
+): SchedulerToolContext {
   return {
     channelId: "C123",
     teamId: TEST_TEAM_ID,
@@ -34,7 +35,7 @@ function createContext(
       canAddReactions: true,
     },
     userText: "schedule this weekly",
-    sandbox: {} as ToolRuntimeContext["sandbox"],
+    state: createPluginState("scheduler"),
     ...overrides,
   };
 }
@@ -46,6 +47,10 @@ async function executeTool<TInput>(tool: any, input: TInput) {
   return await tool.execute(input, {} as any);
 }
 
+function schedulerStore() {
+  return createSchedulerStore(createPluginState("scheduler"));
+}
+
 async function createTask(
   context = createContext(),
   overrides: Record<string, unknown> = {},
@@ -145,7 +150,7 @@ describe("Slack schedule tools", () => {
       },
     });
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toMatchObject([
       {
         destination: { channelId: "C123" },
@@ -164,12 +169,12 @@ describe("Slack schedule tools", () => {
       },
     );
 
-    await expect(rejected).rejects.toThrow(ToolInputError);
+    await expect(rejected).rejects.toThrow(AgentPluginToolInputError);
     await expect(rejected).rejects.toThrow(
       "Active Slack workspace context is invalid.",
     );
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toEqual([]);
   });
 
@@ -201,7 +206,7 @@ describe("Slack schedule tools", () => {
       },
     });
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toMatchObject([
       {
         conversationAccess: {
@@ -247,7 +252,7 @@ describe("Slack schedule tools", () => {
       },
     });
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toMatchObject([
       {
         destination: { channelId: "C123" },
@@ -285,7 +290,7 @@ describe("Slack schedule tools", () => {
       },
     });
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toMatchObject([
       {
         nextRunAtMs: Date.parse("2026-05-28T02:18:48.005Z"),
@@ -305,7 +310,7 @@ describe("Slack schedule tools", () => {
       }),
     ).rejects.toThrow("Provide next_run_at as a valid ISO timestamp.");
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toEqual([]);
   });
 
@@ -316,7 +321,7 @@ describe("Slack schedule tools", () => {
       }),
     ).rejects.toThrow("Provide next_run_at as a valid ISO timestamp.");
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toEqual([]);
   });
 
@@ -330,7 +335,7 @@ describe("Slack schedule tools", () => {
       "Recurring scheduled tasks can run at most once per day.",
     );
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toEqual([]);
   });
 
@@ -397,7 +402,7 @@ describe("Slack schedule tools", () => {
       "Recurring scheduled tasks can run at most once per day.",
     );
     await expect(
-      createStateSchedulerStore().getTask(created.task.id),
+      schedulerStore().getTask(created.task.id),
     ).resolves.toMatchObject({
       schedule: {
         description: "Every Monday at 9am",
@@ -432,7 +437,7 @@ describe("Slack schedule tools", () => {
       },
     });
     await expect(
-      createStateSchedulerStore().getTask(created.task.id),
+      schedulerStore().getTask(created.task.id),
     ).resolves.toMatchObject({
       schedule: {
         kind: "one_off",
@@ -504,7 +509,7 @@ describe("Slack schedule tools", () => {
       },
     });
     await expect(
-      createStateSchedulerStore().getTask(created.task.id),
+      schedulerStore().getTask(created.task.id),
     ).resolves.toMatchObject({
       status: "deleted",
       executionActor: {
@@ -531,8 +536,7 @@ describe("Slack schedule tools", () => {
         credential_subject: null,
       },
     });
-    const tasks =
-      await createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID);
+    const tasks = await schedulerStore().listTasksForTeam(TEST_TEAM_ID);
     expect(tasks).toMatchObject([
       {
         conversationAccess: {
@@ -545,6 +549,34 @@ describe("Slack schedule tools", () => {
     expect(tasks[0]?.credentialSubject).toBeUndefined();
   });
 
+  it("normalizes Slack conversation ids before storing destinations", async () => {
+    const result = await createTask(
+      createContext({ channelId: "slack:D123:1700000000.000" }),
+      {
+        schedule: "In 1 minute",
+        next_run_at: "2026-05-27T00:25:23.000Z",
+        recurrence: undefined,
+      },
+    );
+
+    expect(result).toMatchObject({
+      ok: true,
+      task: {
+        conversation_access: {
+          audience: "direct",
+          visibility: "private",
+        },
+      },
+    });
+    await expect(
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
+    ).resolves.toMatchObject([
+      {
+        destination: { channelId: "D123" },
+      },
+    ]);
+  });
+
   it("creates one-off tasks with an exact timestamp using the default Pacific timezone", async () => {
     vi.useFakeTimers();
     vi.setSystemTime(new Date("2026-05-25T12:00:00.000Z"));
@@ -597,7 +629,7 @@ describe("Slack schedule tools", () => {
       }),
     ).rejects.toThrow("timezone must be a valid IANA time zone.");
     await expect(
-      createStateSchedulerStore().listTasksForTeam(TEST_TEAM_ID),
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
     ).resolves.toEqual([]);
   });
 
@@ -608,7 +640,7 @@ describe("Slack schedule tools", () => {
     })) as {
       task: { id: string };
     };
-    const store = createStateSchedulerStore();
+    const store = schedulerStore();
     const task = await store.getTask(created.task.id);
     expect(task?.schedule.recurrence).toMatchObject({
       interval: 1,
@@ -651,7 +683,7 @@ describe("Slack schedule tools", () => {
     const created = (await createTask(context)) as {
       task: { id: string };
     };
-    const store = createStateSchedulerStore();
+    const store = schedulerStore();
     const task = await store.getTask(created.task.id);
     expect(task).toBeDefined();
     await store.saveTask({
@@ -689,7 +721,7 @@ describe("Slack schedule tools", () => {
     const created = (await createTask(context)) as {
       task: { id: string };
     };
-    const store = createStateSchedulerStore();
+    const store = schedulerStore();
     const task = await store.getTask(created.task.id);
     expect(task).toBeDefined();
     const scheduledNextRunAtMs = Date.parse("2026-06-01T16:00:00.000Z");
@@ -745,7 +777,7 @@ describe("Slack schedule tools", () => {
     const created = (await createTask(context)) as {
       task: { id: string };
     };
-    const store = createStateSchedulerStore();
+    const store = schedulerStore();
     const task = await store.getTask(created.task.id);
     expect(task).toBeDefined();
     await store.saveTask({
@@ -771,7 +803,7 @@ describe("Slack schedule tools", () => {
     expect(paused?.runNowAtMs).toBeUndefined();
   });
 
-  it("removes deleted tasks from scheduler indexes", async () => {
+  it("removes deleted tasks from scheduler listings", async () => {
     const context = createContext();
     const created = (await createTask(context)) as {
       task: { id: string };
@@ -781,14 +813,9 @@ describe("Slack schedule tools", () => {
       task_id: created.task.id,
     });
 
-    const state = getStateAdapter();
-    await state.connect();
-    await expect(state.get<string[]>("junior:scheduler:tasks")).resolves.toBe(
-      null,
-    );
     await expect(
-      state.get<string[]>(`junior:scheduler:team:${TEST_TEAM_ID}:tasks`),
-    ).resolves.toBe(null);
+      schedulerStore().listTasksForTeam(TEST_TEAM_ID),
+    ).resolves.toEqual([]);
   });
 
   it("claims due runs idempotently", async () => {
@@ -796,7 +823,7 @@ describe("Slack schedule tools", () => {
     const created = (await createTask(context)) as {
       task: { id: string };
     };
-    const store = createStateSchedulerStore();
+    const store = schedulerStore();
     const task = await store.getTask(created.task.id);
     expect(task).toBeDefined();
     await store.saveTask({
diff --git a/packages/junior/tests/unit/app-config.test.ts b/packages/junior/tests/unit/app-config.test.ts
index b7a93be2a..a161963b1 100644
--- a/packages/junior/tests/unit/app-config.test.ts
+++ b/packages/junior/tests/unit/app-config.test.ts
@@ -88,9 +88,7 @@ describe("createApp plugin config", () => {
     });
 
     expect(getPluginProviders()).toEqual([]);
-    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual([
-      "scheduler",
-    ]);
+    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual([]);
   });
 
   it("fails loudly when configured plugin package names are invalid", async () => {
@@ -215,10 +213,7 @@ describe("createApp plugin config", () => {
     expect(getPluginProviders().map((plugin) => plugin.manifest.name)).toEqual([
       "trusted",
     ]);
-    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual([
-      "scheduler",
-      "trusted",
-    ]);
+    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual(["trusted"]);
   });
 
   it("rejects duplicate trusted plugin names before mutating app config", async () => {
@@ -235,9 +230,7 @@ describe("createApp plugin config", () => {
       }),
     ).rejects.toThrow('Duplicate trusted plugin name "dupe"');
 
-    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual([
-      "scheduler",
-    ]);
+    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual([]);
     expect(getPluginProviders()).toEqual([]);
   });
 
@@ -254,9 +247,29 @@ describe("createApp plugin config", () => {
       'Trusted plugin name "GitHub" must be a lowercase plugin identifier',
     );
 
-    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual([
-      "scheduler",
-    ]);
+    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual([]);
+    expect(getPluginProviders()).toEqual([]);
+  });
+
+  it("rejects legacy state prefixes outside the trusted plugin namespace", async () => {
+    await createApp({
+      plugins: [],
+    });
+
+    await expect(
+      createApp({
+        plugins: [
+          defineJuniorPlugin({
+            name: "trusted",
+            pluginConfig: { legacyStatePrefixes: ["junior:scheduler"] },
+          }),
+        ],
+      }),
+    ).rejects.toThrow(
+      'Trusted plugin "trusted" legacy state prefix "junior:scheduler" must stay under "junior:trusted"',
+    );
+
+    expect(getAgentPlugins().map((plugin) => plugin.name)).toEqual([]);
     expect(getPluginProviders()).toEqual([]);
   });
 });
diff --git a/packages/junior/tests/unit/slack/tool-registration.test.ts b/packages/junior/tests/unit/slack/tool-registration.test.ts
index cb34d1ac3..4f20f407f 100644
--- a/packages/junior/tests/unit/slack/tool-registration.test.ts
+++ b/packages/junior/tests/unit/slack/tool-registration.test.ts
@@ -1,6 +1,6 @@
 import { afterEach, beforeEach, describe, expect, it } from "vitest";
 import { createTools } from "@/chat/tools";
-import { createSchedulerPlugin } from "@/chat/scheduler/plugin";
+import { schedulerPlugin } from "@sentry/junior-scheduler";
 import { setAgentPlugins } from "@/chat/plugins/agent-hooks";
 import { resolveChannelCapabilities } from "@/chat/tools/channel-capabilities";
 
@@ -16,7 +16,7 @@ function ctx(channelId?: string) {
 
 describe("Slack tool registration", () => {
   beforeEach(() => {
-    setAgentPlugins([createSchedulerPlugin()]);
+    setAgentPlugins([schedulerPlugin()]);
   });
 
   afterEach(() => {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 9c73e4c94..d2595fd69 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -175,6 +175,9 @@ importers:
         specifier: ^4.4.3
         version: 4.4.3
     devDependencies:
+      "@sentry/junior-scheduler":
+        specifier: workspace:*
+        version: link:../junior-scheduler
       "@sentry/node":
         specifier: 10.53.1
         version: 10.53.1
@@ -206,18 +209,6 @@ importers:
         specifier: ^4.1.7
         version: 4.1.7(@edge-runtime/vm@5.0.0)(@opentelemetry/api@1.9.1)(@types/node@25.9.1)(msw@2.14.6(@types/node@25.9.1)(typescript@6.0.3))(vite@8.0.14(@types/node@25.9.1)(esbuild@0.27.7)(jiti@2.7.0)(terser@5.48.0)(tsx@4.22.3)(yaml@2.9.0))
 
-  packages/junior-plugin-api:
-    devDependencies:
-      oxlint:
-        specifier: ^1.66.0
-        version: 1.66.0
-      tsup:
-        specifier: ^8.5.1
-        version: 8.5.1(jiti@2.7.0)(postcss@8.5.15)(tsx@4.22.3)(typescript@6.0.3)(yaml@2.9.0)
-      typescript:
-        specifier: ^6.0.3
-        version: 6.0.3
-
   packages/junior-agent-browser: {}
 
   packages/junior-datadog: {}
@@ -230,6 +221,9 @@ importers:
       "@sentry/junior-github":
         specifier: workspace:*
         version: link:../junior-github
+      "@sentry/junior-scheduler":
+        specifier: workspace:*
+        version: link:../junior-scheduler
       "@sentry/junior-sentry":
         specifier: workspace:*
         version: link:../junior-sentry
@@ -261,6 +255,37 @@ importers:
 
   packages/junior-notion: {}
 
+  packages/junior-plugin-api:
+    devDependencies:
+      oxlint:
+        specifier: ^1.66.0
+        version: 1.66.0
+      tsup:
+        specifier: ^8.5.1
+        version: 8.5.1(jiti@2.7.0)(postcss@8.5.15)(tsx@4.22.3)(typescript@6.0.3)(yaml@2.9.0)
+      typescript:
+        specifier: ^6.0.3
+        version: 6.0.3
+
+  packages/junior-scheduler:
+    dependencies:
+      "@sentry/junior-plugin-api":
+        specifier: workspace:*
+        version: link:../junior-plugin-api
+      "@sinclair/typebox":
+        specifier: ^0.34.49
+        version: 0.34.49
+    devDependencies:
+      "@types/node":
+        specifier: ^25.9.1
+        version: 25.9.1
+      tsup:
+        specifier: ^8.5.1
+        version: 8.5.1(jiti@2.7.0)(postcss@8.5.15)(tsx@4.22.3)(typescript@6.0.3)(yaml@2.9.0)
+      typescript:
+        specifier: ^6.0.3
+        version: 6.0.3
+
   packages/junior-sentry: {}
 
   packages/junior-testing:
@@ -3409,6 +3434,9 @@ packages:
       }
     engines: { node: ">=18" }
 
+  "@sentry/junior-plugin-api@file:packages/junior-plugin-api":
+    resolution: { directory: packages/junior-plugin-api, type: directory }
+
   "@sentry/junior@file:packages/junior":
     resolution: { directory: packages/junior, type: directory }
     hasBin: true
@@ -12389,6 +12417,8 @@ snapshots:
 
   "@sentry/core@10.53.1": {}
 
+  "@sentry/junior-plugin-api@file:packages/junior-plugin-api": {}
+
   "@sentry/junior@file:packages/junior(@aws-sdk/credential-provider-web-identity@3.972.43)(@opentelemetry/api@1.9.1)(@sentry/node@10.53.1)":
     dependencies:
       "@ai-sdk/gateway": 3.0.119(zod@4.4.3)
@@ -12399,6 +12429,7 @@ snapshots:
       "@earendil-works/pi-ai": 0.74.2(@modelcontextprotocol/sdk@1.29.0(zod@4.4.3))(ws@8.20.1)(zod@4.4.3)
       "@logtape/logtape": 2.1.1
       "@modelcontextprotocol/sdk": 1.29.0(zod@4.4.3)
+      "@sentry/junior-plugin-api": file:packages/junior-plugin-api
       "@sentry/node": 10.53.1
       "@sinclair/typebox": 0.34.49
       "@slack/web-api": 7.16.0
@@ -12736,7 +12767,7 @@ snapshots:
 
   "@types/sax@1.2.7":
     dependencies:
-      "@types/node": 24.12.4
+      "@types/node": 25.9.1
 
   "@types/set-cookie-parser@2.4.10":
     dependencies:
diff --git a/scripts/bump-release-versions.mjs b/scripts/bump-release-versions.mjs
index 076c27adf..2398828c6 100644
--- a/scripts/bump-release-versions.mjs
+++ b/scripts/bump-release-versions.mjs
@@ -17,6 +17,7 @@ const files = [
   "packages/junior-hex/package.json",
   "packages/junior-linear/package.json",
   "packages/junior-notion/package.json",
+  "packages/junior-scheduler/package.json",
   "packages/junior-sentry/package.json",
 ];