diff --git a/packages-workflows/process-web-submission.yml b/packages-workflows/process-web-submission.yml
index 683218c..062cc14 100644
--- a/packages-workflows/process-web-submission.yml
+++ b/packages-workflows/process-web-submission.yml
@@ -36,8 +36,8 @@ jobs:
         id: validate
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          DEB_URL: ${{ github.event.client_payload.url }}
-          WANT_SHA: ${{ github.event.client_payload.sha256 }}
+          DEB_URL: ${{ github.event.client_payload.binary.url }}
+          WANT_SHA: ${{ github.event.client_payload.binary.sha256 }}
           SUBMITTER: ${{ github.event.client_payload.login }}
           # JSON array of the submitter's verified emails (from the Worker,
           # which read them via the user's OAuth token — trusted).
@@ -271,9 +271,9 @@ jobs:
         if: steps.validate.outputs.errors == '' && steps.meta.outputs.errors == ''
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          DEB_URL: ${{ github.event.client_payload.url }}
-          WANT_SHA: ${{ github.event.client_payload.sha256 }}
-          SIZE: ${{ github.event.client_payload.size }}
+          DEB_URL: ${{ github.event.client_payload.binary.url }}
+          WANT_SHA: ${{ github.event.client_payload.binary.sha256 }}
+          SIZE: ${{ github.event.client_payload.binary.size }}
           SUBMITTER: ${{ github.event.client_payload.login }}
           EMAILS_JSON: ${{ toJSON(github.event.client_payload.emails) }}
           PKG: ${{ steps.validate.outputs.pkg }}
diff --git a/worker/src/index.js b/worker/src/index.js
index 9a63a18..91d2154 100644
--- a/worker/src/index.js
+++ b/worker/src/index.js
@@ -254,9 +254,10 @@ async function apiSubmit(request, env) {
         version,
         architecture: arch,
         filename: canonical,
-        url: asset.browser_download_url,
-        sha256,
-        size: buf.byteLength,
+        // url/sha256/size are nested under one key: repository_dispatch caps
+        // client_payload at 10 top-level properties, and with `store` we'd
+        // otherwise hit 12 → GitHub returns HTTP 422.
+        binary: { url: asset.browser_download_url, sha256, size: buf.byteLength },
         source_repo: sourceRepo,
         ...(store && store.payload ? { store: store.payload } : {}),
       },