diff --git a/lib/spark.js b/lib/spark.js
index 86e725d..05662c0 100644
--- a/lib/spark.js
+++ b/lib/spark.js
@@ -230,6 +230,11 @@ export default class Spark {
       participantAddress: Zinnia.walletAddress,
       stationId: Zinnia.stationId,
     }
+    if (task.isOnDemand) {
+      payload.excludeFromRSR = true
+      console.log('Note: This is an on-demand task; marking for RSR exclusion.')
+    }
+
     console.log('%o', payload)
     const res = await this.#fetch('https://api.filspark.com/measurements', {
       method: 'POST',
@@ -299,6 +304,14 @@ export default class Spark {
     }
     console.error(err)
   }
+  /**
+   * Public wrapper to inject an on-demand task
+   *
+   * @param {Task} task - A retrieval task with cid and minerId
+   */
+  queueOnDemandRetrieval(task) {
+    return this.#tasker.queueOnDemandTask(task)
+  }
 }
 
 /**
diff --git a/lib/tasker.js b/lib/tasker.js
index 765a5b9..e3b6731 100644
--- a/lib/tasker.js
+++ b/lib/tasker.js
@@ -13,6 +13,7 @@ export class Tasker {
   #lastRoundUrl
   /** @type {Task[]} */
   #remainingRoundTasks
+  #onDemandTasks
   #fetch
   #activity
 
@@ -35,10 +36,17 @@ export class Tasker {
     // retrieval tasks we have already executed
     this.#lastRoundUrl = 'unknown'
     this.#remainingRoundTasks = []
+
+    this.#onDemandTasks = []
   }
 
   /** @returns {Task | undefined} */
   async next() {
+    if (this.#onDemandTasks.length > 0) {
+      console.log('Returning on-demand retrieval task.')
+      return this.#onDemandTasks.pop()
+    }
+
     await this.#updateCurrentRound()
     return this.#remainingRoundTasks.pop()
   }
@@ -88,6 +96,27 @@ export class Tasker {
 
     this.#lastRoundUrl = roundUrl
   }
+  /**
+   * Queue a retrieval task for immediate execution. This task will be processed
+   * before regular round-based tasks.
+   *
+   * @param {Task} task - A valid retrieval task ({ cid, minerId })
+   */
+  queueOnDemandTask(task) {
+    if (
+      !task ||
+      typeof task.cid !== 'string' ||
+      typeof task.minerId !== 'string'
+    ) {
+      throw new Error(
+        'Invalid on-demand task. Must include cid and minerId as strings.',
+      )
+    }
+    // for future improvements prevent duplicates or apply rate limiting
+    console.log('Queued on-demand task for miner:', task.minerId)
+    task.isOnDemand = true
+    this.#onDemandTasks.push(task)
+  }
 }
 
 const textEncoder = new TextEncoder()
diff --git a/scripts/trigger-on-demand.js b/scripts/trigger-on-demand.js
new file mode 100644
index 0000000..be6a04b
--- /dev/null
+++ b/scripts/trigger-on-demand.js
@@ -0,0 +1,12 @@
+// this’s a manual testing tool useful for demonstration
+import Spark from '../lib/spark.js'
+
+const spark = new Spark()
+
+const testTask = {
+  cid: 'bafyreih4wq2ljuzhnn6pzl7tny7khzekqjx7yp6h5rvfbx2hrwrtp6mpcq',
+  minerId: 't01234',
+}
+
+spark.queueOnDemandRetrieval(testTask)
+console.log('On-demand task queued successfully.')
diff --git a/test/spark.js b/test/spark.js
index 9e62718..23d7b10 100644
--- a/test/spark.js
+++ b/test/spark.js
@@ -415,6 +415,46 @@ test('submitRetrieval', async () => {
   ])
 })
 
+test('submitMeasurement adds excludeFromRSR for on-demand tasks', async () => {
+  let capturedPayload = null
+
+  const spark = new Spark({
+    fetch: async (url, allOpts) => {
+      if (url.includes('/measurements')) {
+        capturedPayload = JSON.parse(allOpts.body)
+        return {
+          status: 200,
+          ok: true,
+          async json() {
+            return { id: 456 }
+          },
+        }
+      }
+
+      // fallback response for anything else
+      return {
+        status: 200,
+        ok: true,
+        async json() {
+          return {}
+        },
+        headers: new Headers(),
+      }
+    },
+  })
+
+  const task = {
+    cid: 'bafytestondemand',
+    minerId: 't0999',
+    isOnDemand: true,
+  }
+  const stats = {}
+
+  await spark.submitMeasurement(task, stats)
+
+  assertEquals(capturedPayload.excludeFromRSR, true)
+})
+
 test('calculateDelayBeforeNextTask() returns value based on average task duration', () => {
   const delay = calculateDelayBeforeNextTask({
     lastTaskDurationInMs: 3_000,
diff --git a/test/tasker.test.js b/test/tasker.test.js
index d783cfc..3a5c4f2 100644
--- a/test/tasker.test.js
+++ b/test/tasker.test.js
@@ -2,7 +2,12 @@
 
 import { test } from 'zinnia:test'
 import { assertEquals } from 'zinnia:assert'
-import { getStationKey, getTaskKey, pickTasks } from '../lib/tasker.js'
+import {
+  getStationKey,
+  getTaskKey,
+  pickTasksForNode,
+  Tasker,
+} from '../lib/tasker.js'
 
 const RANDOMNESS =
   'fc90e50dcdf20886b56c038b30fa921a5e57c532ea448dadcc209e44eec0445e'
@@ -36,7 +41,7 @@ test('pickTasksForNode', async () => {
     { cid: 'bafytwo', minerId: 'f040' },
   ]
 
-  const selectedTasks = await pickTasks({
+  const selectedTasks = await pickTasksForNode({
     tasks: allTasks,
     stationId: 'some-station-id',
     randomness: RANDOMNESS,
@@ -49,3 +54,23 @@ test('pickTasksForNode', async () => {
     { cid: 'bafytwo', minerId: 'f020' },
   ])
 })
+test('on-demand tasks are returned before regular tasks', async () => {
+  const dummyFetch = async () => ({
+    status: 302,
+    headers: new Map([['location', '/mock-round']]),
+    json: async () => ({
+      retrievalTasks: [{ cid: 'bafyregular', minerId: 't0999' }],
+      maxTasksPerNode: 1,
+    }),
+  })
+
+  const tasker = new Tasker({ fetch: dummyFetch })
+
+  // Add an on-demand task first
+  const onDemandTask = { cid: 'bafyondemand', minerId: 't01234' }
+  tasker.queueOnDemandTask(onDemandTask)
+
+  const task = await tasker.next()
+  assertEquals(task.cid, onDemandTask.cid)
+  assertEquals(task.minerId, onDemandTask.minerId)
+})