diff --git a/__tests__/main.test.ts b/__tests__/main.test.ts
index b9ef95e..eec35ca 100644
--- a/__tests__/main.test.ts
+++ b/__tests__/main.test.ts
@@ -139,7 +139,9 @@ describe('run', () => {
 
       expect(reportJobErrorSpy).toHaveBeenCalledWith({
         'error-type': 'actions_workflow_unknown',
-        'error-detail': 'error getting job details'
+        'error-details': {
+          'action-error': 'error getting job details'
+        }
       })
       expect(markJobAsProcessedSpy).toHaveBeenCalled()
     })
@@ -173,7 +175,9 @@ describe('run', () => {
 
       expect(reportJobErrorSpy).toHaveBeenCalledWith({
         'error-type': 'actions_workflow_unknown',
-        'error-detail': 'error getting credentials'
+        'error-details': {
+          'action-error': 'error getting credentials'
+        }
       })
       expect(markJobAsProcessedSpy).toHaveBeenCalled()
     })
@@ -207,7 +211,9 @@ describe('run', () => {
 
       expect(reportJobErrorSpy).toHaveBeenCalledWith({
         'error-type': 'actions_workflow_image',
-        'error-detail': 'error pulling an image'
+        'error-details': {
+          'action-error': 'error pulling an image'
+        }
       })
       expect(markJobAsProcessedSpy).toHaveBeenCalled()
     })
@@ -241,7 +247,9 @@ describe('run', () => {
 
       expect(reportJobErrorSpy).toHaveBeenCalledWith({
         'error-type': 'actions_workflow_updater',
-        'error-detail': 'error running the update'
+        'error-details': {
+          'action-error': 'error running the update'
+        }
       })
       expect(markJobAsProcessedSpy).toHaveBeenCalled()
     })
diff --git a/src/api-client.ts b/src/api-client.ts
index 5bdc056..fbd7878 100644
--- a/src/api-client.ts
+++ b/src/api-client.ts
@@ -22,7 +22,9 @@ export type JobDetails = {
 
 export type JobError = {
   'error-type': string
-  'error-detail': any
+  'error-details': {
+    'action-error': string
+  }
 }
 
 export type Credential = {
@@ -39,6 +41,12 @@ export class ApiClient {
     readonly params: JobParameters
   ) {}
 
+  // We use a static unknown SHA when making a job as complete from the action
+  // to remain in parity with the existing runner.
+  UnknownSha = {
+    'base-commit-sha': 'unknown'
+  }
+
   async getJobDetails(): Promise<JobDetails> {
     const detailsURL = `/update_jobs/${this.params.jobId}/details`
     const res = await this.client.get(detailsURL, {
@@ -65,25 +73,29 @@ export class ApiClient {
 
   async reportJobError(error: JobError): Promise<void> {
     const recordErrorURL = `/update_jobs/${this.params.jobId}/record_update_job_error`
-    const res = await this.client.post(recordErrorURL, error, {
-      headers: {Authorization: this.params.jobToken}
-    })
-    if (res.status !== 200) {
+    const res = await this.client.post(
+      recordErrorURL,
+      {data: error},
+      {
+        headers: {Authorization: this.params.jobToken}
+      }
+    )
+    if (res.status !== 204) {
       throw new Error(`Unexpected status code: ${res.status}`)
     }
-
-    return res.data.data.attributes
   }
 
   async markJobAsProcessed(): Promise<void> {
     const markAsProcessedURL = `/update_jobs/${this.params.jobId}/mark_as_processed`
-    const res = await this.client.get(markAsProcessedURL, {
-      headers: {Authorization: this.params.jobToken}
-    })
-    if (res.status !== 200) {
+    const res = await this.client.patch(
+      markAsProcessedURL,
+      {data: this.UnknownSha},
+      {
+        headers: {Authorization: this.params.jobToken}
+      }
+    )
+    if (res.status !== 204) {
       throw new Error(`Unexpected status code: ${res.status}`)
     }
-
-    return res.data.data.attributes
   }
 }
diff --git a/src/main.ts b/src/main.ts
index 62e6693..f8d339a 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -92,7 +92,9 @@ async function failJob(
 ): Promise<void> {
   await apiClient.reportJobError({
     'error-type': errorType,
-    'error-detail': error.message
+    'error-details': {
+      'action-error': error.message
+    }
   })
   await apiClient.markJobAsProcessed()
   core.setFailed(error.message)