From 1355b627e7e6c62c4c75920372d71e15400fc0cd Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 30 Apr 2026 11:25:55 +0800
Subject: [PATCH 01/18] Use issue with PR compare link instead of creating PR
 directly

GitHub Actions is not permitted to create pull requests in this repo, so the regenerate workflow now creates/updates a tracking issue containing a pre-filled compare URL. Maintainers click the link to open the PR.
---
 .../workflows/typespec-python-regenerate.yml  | 67 ++++++++++++-------
 1 file changed, 43 insertions(+), 24 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index aed7ede5a090..3517a294ce34 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -162,8 +162,8 @@ jobs:
           echo "has_changes=true" >> $GITHUB_OUTPUT
           echo "branch=$BRANCH" >> $GITHUB_OUTPUT
 
-      - name: Create or update Pull Request
-        id: create-pr
+      - name: Create or update tracking issue with PR link
+        id: create-issue
         if: steps.push-changes.outputs.has_changes == 'true'
         env:
           GH_TOKEN: ${{ github.token }}
@@ -172,36 +172,55 @@ jobs:
           EMITTER="${{ steps.emitter-info.outputs.emitter_name }}"
           VERSION="${{ steps.emitter-info.outputs.emitter_version }}"
           BRANCH="${{ steps.push-changes.outputs.branch }}"
+          REPO="${{ github.repository }}"
+          SERVER="${{ github.server_url }}"
+          RUN_URL="${SERVER}/${REPO}/actions/runs/${{ github.run_id }}"
+
           TITLE="[typespec-python] Regenerate tests with ${EMITTER}@${VERSION}"
-          BODY="Automated regeneration of TypeSpec Python generated tests.
+
+          # Build a "compare" URL that opens the PR creation page pre-filled.
+          # GitHub Actions cannot create PRs directly (org policy), so the
+          # reviewer just needs to click the link to open the PR.
+          PR_TITLE_ENC=$(jq -rn --arg t "$TITLE" '$t|@uri')
+          PR_BODY_RAW="Automated regeneration of TypeSpec Python generated tests.
 
           - Emitter: \`${EMITTER}@${VERSION}\`
-          - Workflow run: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
+          - Workflow run: ${RUN_URL}
 
           This PR was auto-generated."
+          PR_BODY_ENC=$(jq -rn --arg b "$PR_BODY_RAW" '$b|@uri')
+          COMPARE_URL="${SERVER}/${REPO}/compare/main...${BRANCH}?quick_pull=1&title=${PR_TITLE_ENC}&body=${PR_BODY_ENC}"
+
+          ISSUE_BODY="GitHub Actions is not permitted to create pull requests in this repository, so this issue tracks the regeneration instead.
+
+          **Click the link below to open a pre-filled PR:**
+
+          👉 [Create pull request from \`${BRANCH}\`](${COMPARE_URL})
+
+          Details:
+          - Emitter: \`${EMITTER}@${VERSION}\`
+          - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
+          - Workflow run: ${RUN_URL}
 
-          # Check if a PR already exists for this branch
-          EXISTING_PR=$(gh pr list --head "$BRANCH" --json number --jq '.[0].number' || echo "")
-          if [ -n "$EXISTING_PR" ]; then
-            echo "Updating existing PR #$EXISTING_PR"
-            gh pr edit "$EXISTING_PR" --title "$TITLE" --body "$BODY" --add-reviewer iscai-msft,msyyc
-            PR_NUMBER="$EXISTING_PR"
+          cc @iscai-msft @msyyc"
+
+          # Reuse an existing open tracking issue if one exists (matched by title).
+          EXISTING_ISSUE=$(gh issue list --state open --search "\"$TITLE\" in:title" \
+            --json number,title --jq ".[] | select(.title == \"$TITLE\") | .number" | head -n1 || echo "")
+
+          if [ -n "$EXISTING_ISSUE" ]; then
+            echo "Updating existing issue #$EXISTING_ISSUE"
+            gh issue edit "$EXISTING_ISSUE" --body "$ISSUE_BODY"
+            ISSUE_NUMBER="$EXISTING_ISSUE"
           else
-            echo "Creating new PR"
-            PR_NUMBER=$(gh pr create --head "$BRANCH" --base main \
-              --title "$TITLE" --body "$BODY" \
-              --reviewer iscai-msft,msyyc | grep -oP '\d+$')
-            echo "Created PR #$PR_NUMBER"
+            echo "Creating new tracking issue"
+            ISSUE_URL=$(gh issue create --title "$TITLE" --body "$ISSUE_BODY" \
+              --label "typespec-python" \
+              --assignee iscai-msft,msyyc)
+            echo "Created issue: $ISSUE_URL"
+            ISSUE_NUMBER="${ISSUE_URL##*/}"
           fi
-          echo "pr_number=$PR_NUMBER" >> $GITHUB_OUTPUT
-
-      - name: Enable auto-merge
-        if: steps.push-changes.outputs.has_changes == 'true'
-        env:
-          GH_TOKEN: ${{ github.token }}
-        run: |
-          gh pr merge "${{ steps.create-pr.outputs.pr_number }}" --auto --squash || \
-            echo "::warning::Auto-merge could not be enabled (may require branch protection rules)"
+          echo "issue_number=$ISSUE_NUMBER" >> $GITHUB_OUTPUT
 
   notify-on-failure:
     name: "Notify on failure"

From 0c525c937ea580087db8b6804a2dabdedc3b9cb1 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 30 Apr 2026 11:39:12 +0800
Subject: [PATCH 02/18] Update .github/workflows/typespec-python-regenerate.yml

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 .github/workflows/typespec-python-regenerate.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 3517a294ce34..1a83431766bd 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -206,7 +206,7 @@ jobs:
 
           # Reuse an existing open tracking issue if one exists (matched by title).
           EXISTING_ISSUE=$(gh issue list --state open --search "\"$TITLE\" in:title" \
-            --json number,title --jq ".[] | select(.title == \"$TITLE\") | .number" | head -n1 || echo "")
+            --json number,title | jq -r --arg title "$TITLE" '.[] | select(.title == $title) | .number' | head -n1 || echo "")
 
           if [ -n "$EXISTING_ISSUE" ]; then
             echo "Updating existing issue #$EXISTING_ISSUE"

From c7800462b978538bdc9e7fd595eb19dbbe68ae62 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 30 Apr 2026 11:40:34 +0800
Subject: [PATCH 03/18] Update .github/workflows/typespec-python-regenerate.yml

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 .github/workflows/typespec-python-regenerate.yml | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 1a83431766bd..d643aba39a5a 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -214,11 +214,11 @@ jobs:
             ISSUE_NUMBER="$EXISTING_ISSUE"
           else
             echo "Creating new tracking issue"
-            ISSUE_URL=$(gh issue create --title "$TITLE" --body "$ISSUE_BODY" \
+            ISSUE_NUMBER=$(gh issue create --title "$TITLE" --body "$ISSUE_BODY" \
               --label "typespec-python" \
-              --assignee iscai-msft,msyyc)
-            echo "Created issue: $ISSUE_URL"
-            ISSUE_NUMBER="${ISSUE_URL##*/}"
+              --assignee iscai-msft,msyyc \
+              --json number --jq '.number')
+            echo "Created issue #$ISSUE_NUMBER"
           fi
           echo "issue_number=$ISSUE_NUMBER" >> $GITHUB_OUTPUT
 

From e05f117acb12d7fb051ac552a930d3ab8e494f95 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 30 Apr 2026 03:42:51 +0000
Subject: [PATCH 04/18] Enforce labels/assignees on existing issue update

Agent-Logs-Url: https://github.com/Azure/azure-sdk-for-python/sessions/7245d6ed-22c5-48c9-8004-9edecc51602d

Co-authored-by: msyyc <70930885+msyyc@users.noreply.github.com>
---
 .github/workflows/typespec-python-regenerate.yml | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index d643aba39a5a..2f7f254cf662 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -210,7 +210,10 @@ jobs:
 
           if [ -n "$EXISTING_ISSUE" ]; then
             echo "Updating existing issue #$EXISTING_ISSUE"
-            gh issue edit "$EXISTING_ISSUE" --body "$ISSUE_BODY"
+            # Re-apply expected label and assignees in case they were removed from the existing issue.
+            gh issue edit "$EXISTING_ISSUE" --body "$ISSUE_BODY" \
+              --add-label "typespec-python" \
+              --add-assignee iscai-msft,msyyc
             ISSUE_NUMBER="$EXISTING_ISSUE"
           else
             echo "Creating new tracking issue"

From 7927e3db0fc56d7f49eba0629e2f956e7c5bd5dc Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 30 Apr 2026 11:56:25 +0800
Subject: [PATCH 05/18] Update typespec-python-regenerate.yml

---
 .github/workflows/typespec-python-regenerate.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 2f7f254cf662..5c1f4264ba42 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -125,7 +125,7 @@ jobs:
         working-directory: _typespec/packages/http-client-python
         run: |
           EMITTER="${{ steps.emitter-info.outputs.emitter_name }}"
-          npm run regenerate -- --emitterName "$EMITTER"
+          npm run regenerate
 
       - name: Copy regenerated tests
         run: |

From 37846dd8c499cef0fff9ef89a31c849ed3c96145 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 02:45:06 +0000
Subject: [PATCH 06/18] simplify input

---
 .../workflows/typespec-python-regenerate.yml  | 76 +++++--------------
 1 file changed, 19 insertions(+), 57 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 5c1f4264ba42..53b388986153 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -1,25 +1,14 @@
 name: TypeSpec Python Regenerate Tests
 
 on:
-  # Trigger when eng/emitter-package.json is updated on main (branded emitter version bump)
+  # Trigger when eng/emitter-package.json is updated on main (uses default microsoft/typespec@main)
   push:
     branches: [main]
     paths:
       - "eng/emitter-package.json"
-  # Allow manual triggering with emitter choice
+  # Allow manual triggering
   workflow_dispatch:
     inputs:
-      emitter:
-        description: "Which emitter to regenerate with"
-        required: true
-        type: choice
-        options:
-          - "branded (@azure-tools/typespec-python)"
-          - "unbranded (@typespec/http-client-python)"
-        default: "branded (@azure-tools/typespec-python)"
-      version:
-        description: "Emitter version (leave empty to use version from emitter-package.json for branded, or latest for unbranded)"
-        required: false
       typespec_ref:
         description: "Git ref (branch, tag, or SHA) of typespec repo to build regeneration infrastructure from"
         required: false
@@ -49,33 +38,15 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Determine emitter to use
-        id: emitter-info
+      - name: Resolve TypeSpec repo/ref
+        id: typespec-info
         run: |
           set -euo pipefail
-          if [ "${{ github.event_name }}" = "push" ]; then
-            # Push trigger: always use branded emitter at version from emitter-package.json
-            EMITTER_NAME="@azure-tools/typespec-python"
-            VERSION=$(jq -r '.dependencies["@azure-tools/typespec-python"]' eng/emitter-package.json)
-            echo "Push trigger: using branded emitter @ $VERSION"
-          elif [[ "${{ github.event.inputs.emitter }}" == branded* ]]; then
-            EMITTER_NAME="@azure-tools/typespec-python"
-            VERSION="${{ github.event.inputs.version }}"
-            if [ -z "$VERSION" ]; then
-              VERSION=$(jq -r '.dependencies["@azure-tools/typespec-python"]' eng/emitter-package.json)
-              echo "No version specified, using emitter-package.json version: $VERSION"
-            fi
-          else
-            EMITTER_NAME="@typespec/http-client-python"
-            VERSION="${{ github.event.inputs.version }}"
-            if [ -z "$VERSION" ]; then
-              VERSION=$(npm view @typespec/http-client-python version 2>/dev/null)
-              echo "No version specified, using latest npm version: $VERSION"
-            fi
-          fi
-          echo "emitter_name=$EMITTER_NAME" >> $GITHUB_OUTPUT
-          echo "emitter_version=$VERSION" >> $GITHUB_OUTPUT
-          echo "::notice::Regenerating with $EMITTER_NAME@$VERSION"
+          REPO="${{ github.event.inputs.typespec_repo || 'microsoft/typespec' }}"
+          REF="${{ github.event.inputs.typespec_ref || 'main' }}"
+          echo "typespec_repo=$REPO" >> $GITHUB_OUTPUT
+          echo "typespec_ref=$REF" >> $GITHUB_OUTPUT
+          echo "::notice::Regenerating from ${REPO}@${REF}"
 
       - name: Checkout microsoft/typespec
         # SHA corresponds to actions/checkout@v6
@@ -84,8 +55,8 @@ jobs:
         # in regenerate.ts, which breaks unbranded package name detection
         uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
         with:
-          repository: ${{ github.event.inputs.typespec_repo || 'microsoft/typespec' }}
-          ref: ${{ github.event.inputs.typespec_ref || 'main' }}
+          repository: ${{ steps.typespec-info.outputs.typespec_repo }}
+          ref: ${{ steps.typespec-info.outputs.typespec_ref }}
           path: _typespec
           fetch-depth: 0
 
@@ -107,14 +78,6 @@ jobs:
           npm install --ignore-scripts
           npm run build
 
-      - name: Install target emitter
-        working-directory: _typespec/packages/http-client-python
-        run: |
-          EMITTER="${{ steps.emitter-info.outputs.emitter_name }}"
-          VERSION="${{ steps.emitter-info.outputs.emitter_version }}"
-          echo "Installing $EMITTER@$VERSION"
-          npm install "${EMITTER}@${VERSION}"
-
       - name: Prepare Python environment
         working-directory: _typespec/packages/http-client-python
         run: |
@@ -124,7 +87,6 @@ jobs:
       - name: Regenerate tests
         working-directory: _typespec/packages/http-client-python
         run: |
-          EMITTER="${{ steps.emitter-info.outputs.emitter_name }}"
           npm run regenerate
 
       - name: Copy regenerated tests
@@ -143,8 +105,7 @@ jobs:
         id: push-changes
         run: |
           set -euo pipefail
-          EMITTER="${{ steps.emitter-info.outputs.emitter_name }}"
-          VERSION="${{ steps.emitter-info.outputs.emitter_version }}"
+          REPO_REF="${{ steps.typespec-info.outputs.typespec_repo }}@${{ steps.typespec-info.outputs.typespec_ref }}"
           BRANCH="auto/typespec-python-regenerate"
           git config user.name "github-actions[bot]"
           git config user.email "github-actions[bot]@users.noreply.github.com"
@@ -157,7 +118,7 @@ jobs:
           fi
 
           git checkout -B "$BRANCH"
-          git commit -m "[typespec-python] Regenerate tests with ${EMITTER}@${VERSION}"
+          git commit -m "[typespec-python] Regenerate tests from ${REPO_REF}"
           git push origin "$BRANCH" --force
           echo "has_changes=true" >> $GITHUB_OUTPUT
           echo "branch=$BRANCH" >> $GITHUB_OUTPUT
@@ -169,14 +130,15 @@ jobs:
           GH_TOKEN: ${{ github.token }}
         run: |
           set -euo pipefail
-          EMITTER="${{ steps.emitter-info.outputs.emitter_name }}"
-          VERSION="${{ steps.emitter-info.outputs.emitter_version }}"
+          TS_REPO="${{ steps.typespec-info.outputs.typespec_repo }}"
+          TS_REF="${{ steps.typespec-info.outputs.typespec_ref }}"
           BRANCH="${{ steps.push-changes.outputs.branch }}"
           REPO="${{ github.repository }}"
           SERVER="${{ github.server_url }}"
           RUN_URL="${SERVER}/${REPO}/actions/runs/${{ github.run_id }}"
+          TS_REF_URL="${SERVER}/${TS_REPO}/tree/${TS_REF}"
 
-          TITLE="[typespec-python] Regenerate tests with ${EMITTER}@${VERSION}"
+          TITLE="[typespec-python] Regenerate tests from ${TS_REPO}@${TS_REF}"
 
           # Build a "compare" URL that opens the PR creation page pre-filled.
           # GitHub Actions cannot create PRs directly (org policy), so the
@@ -184,7 +146,7 @@ jobs:
           PR_TITLE_ENC=$(jq -rn --arg t "$TITLE" '$t|@uri')
           PR_BODY_RAW="Automated regeneration of TypeSpec Python generated tests.
 
-          - Emitter: \`${EMITTER}@${VERSION}\`
+          - Source: \`${TS_REPO}@${TS_REF}\` (${TS_REF_URL})
           - Workflow run: ${RUN_URL}
 
           This PR was auto-generated."
@@ -198,7 +160,7 @@ jobs:
           👉 [Create pull request from \`${BRANCH}\`](${COMPARE_URL})
 
           Details:
-          - Emitter: \`${EMITTER}@${VERSION}\`
+          - Source: [\`${TS_REPO}@${TS_REF}\`](${TS_REF_URL})
           - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
           - Workflow run: ${RUN_URL}
 

From b696ebece87d42f366bc5c697b35c8b814dd8e22 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 02:47:46 +0000
Subject: [PATCH 07/18] add codeowner for typespec-python-regenerate action

---
 .github/CODEOWNERS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index 9977cc01bf8b..9108d380ce3c 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -837,6 +837,7 @@
 /eng/common/                                                         @Azure/azure-sdk-eng
 /eng/tools/                                                          @scbedd @mccoyp
 /.github/workflows/                                                  @Azure/azure-sdk-eng
+/.github/workflows/typespec-python-regenerate.yml                    @Azure/azure-sdk-eng @tadelesh @msyyc @iscai-msft @ChenxiJiang333
 /.github/CODEOWNERS                                                  @lmazuel @xiangyan99 @kashifkhan @Azure/azure-sdk-eng
 /.github/copilot-instructions.md                                     @l0lawrence @praveenkuttappan @maririos
 /.github/prompts/                                                    @mccoyp @l0lawrence @benbp

From fa40875949ab3c195a8a62616cb4c6684cdedcb3 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 03:21:36 +0000
Subject: [PATCH 08/18] update

---
 .../workflows/typespec-python-regenerate.yml  | 85 ++++++++++++++-----
 1 file changed, 66 insertions(+), 19 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 53b388986153..29bf96a8bedd 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -10,13 +10,9 @@ on:
   workflow_dispatch:
     inputs:
       typespec_ref:
-        description: "Git ref (branch, tag, or SHA) of typespec repo to build regeneration infrastructure from"
+        description: "Either 'main' (microsoft/typespec@main) or a microsoft/typespec pull request URL (e.g. https://github.com/microsoft/typespec/pull/1234). The PR's head repo + SHA will be checked out."
         required: false
         default: "main"
-      typespec_repo:
-        description: "TypeSpec repository (owner/repo) to checkout from (default: microsoft/typespec)"
-        required: false
-        default: "microsoft/typespec"
 
 permissions:
   contents: write
@@ -40,13 +36,49 @@ jobs:
 
       - name: Resolve TypeSpec repo/ref
         id: typespec-info
+        env:
+          GH_TOKEN: ${{ github.token }}
         run: |
           set -euo pipefail
-          REPO="${{ github.event.inputs.typespec_repo || 'microsoft/typespec' }}"
-          REF="${{ github.event.inputs.typespec_ref || 'main' }}"
+          INPUT="${{ github.event.inputs.typespec_ref || 'main' }}"
+          # Default: microsoft/typespec @ main
+          REPO="microsoft/typespec"
+          REF="main"
+          DISPLAY_REF="main"
+          REF_URL="https://github.com/${REPO}/tree/main"
+          PR_NUMBER=""
+
+          # Accept a microsoft/typespec PR URL and resolve it to head repo + SHA.
+          # Example: https://github.com/microsoft/typespec/pull/1234
+          if [[ "$INPUT" =~ ^https://github\.com/([^/]+)/([^/]+)/pull/([0-9]+)/?$ ]]; then
+            PR_OWNER="${BASH_REMATCH[1]}"
+            PR_REPO_NAME="${BASH_REMATCH[2]}"
+            PR_NUMBER="${BASH_REMATCH[3]}"
+            if [ "$PR_OWNER/$PR_REPO_NAME" != "microsoft/typespec" ]; then
+              echo "::error::Only pull request URLs from microsoft/typespec are accepted (got ${PR_OWNER}/${PR_REPO_NAME})."
+              exit 1
+            fi
+            echo "Resolving PR #${PR_NUMBER} from ${PR_OWNER}/${PR_REPO_NAME}..."
+            PR_JSON=$(gh pr view "$PR_NUMBER" --repo "${PR_OWNER}/${PR_REPO_NAME}" \
+              --json headRefOid,headRepositoryOwner,headRepository)
+            HEAD_SHA=$(echo "$PR_JSON" | jq -r '.headRefOid')
+            HEAD_OWNER=$(echo "$PR_JSON" | jq -r '.headRepositoryOwner.login')
+            HEAD_REPO_NAME=$(echo "$PR_JSON" | jq -r '.headRepository.name')
+            REPO="${HEAD_OWNER}/${HEAD_REPO_NAME}"
+            REF="${HEAD_SHA}"
+            DISPLAY_REF="PR #${PR_NUMBER} @ ${HEAD_SHA:0:7}"
+            REF_URL="${INPUT}"
+          elif [ "$INPUT" != "main" ]; then
+            echo "::error::typespec_ref must be 'main' or a microsoft/typespec pull request URL (got: ${INPUT})."
+            exit 1
+          fi
+
           echo "typespec_repo=$REPO" >> $GITHUB_OUTPUT
           echo "typespec_ref=$REF" >> $GITHUB_OUTPUT
-          echo "::notice::Regenerating from ${REPO}@${REF}"
+          echo "typespec_display_ref=$DISPLAY_REF" >> $GITHUB_OUTPUT
+          echo "typespec_ref_url=$REF_URL" >> $GITHUB_OUTPUT
+          echo "typespec_pr_number=$PR_NUMBER" >> $GITHUB_OUTPUT
+          echo "::notice::Regenerating from ${REPO}@${DISPLAY_REF}"
 
       - name: Checkout microsoft/typespec
         # SHA corresponds to actions/checkout@v6
@@ -105,8 +137,14 @@ jobs:
         id: push-changes
         run: |
           set -euo pipefail
-          REPO_REF="${{ steps.typespec-info.outputs.typespec_repo }}@${{ steps.typespec-info.outputs.typespec_ref }}"
-          BRANCH="auto/typespec-python-regenerate"
+          PR_NUMBER="${{ steps.typespec-info.outputs.typespec_pr_number }}"
+          if [ -n "$PR_NUMBER" ]; then
+            SOURCE_LABEL="microsoft/typespec PR #${PR_NUMBER}"
+            BRANCH="auto/typespec-python-regenerate-${PR_NUMBER}"
+          else
+            SOURCE_LABEL="microsoft/typespec@main"
+            BRANCH="auto/typespec-python-regenerate"
+          fi
           git config user.name "github-actions[bot]"
           git config user.email "github-actions[bot]@users.noreply.github.com"
 
@@ -118,7 +156,7 @@ jobs:
           fi
 
           git checkout -B "$BRANCH"
-          git commit -m "[typespec-python] Regenerate tests from ${REPO_REF}"
+          git commit -m "[typespec-python] Regenerate tests from ${SOURCE_LABEL}"
           git push origin "$BRANCH" --force
           echo "has_changes=true" >> $GITHUB_OUTPUT
           echo "branch=$BRANCH" >> $GITHUB_OUTPUT
@@ -130,23 +168,32 @@ jobs:
           GH_TOKEN: ${{ github.token }}
         run: |
           set -euo pipefail
-          TS_REPO="${{ steps.typespec-info.outputs.typespec_repo }}"
-          TS_REF="${{ steps.typespec-info.outputs.typespec_ref }}"
+          TS_REF_URL="${{ steps.typespec-info.outputs.typespec_ref_url }}"
+          PR_NUMBER="${{ steps.typespec-info.outputs.typespec_pr_number }}"
           BRANCH="${{ steps.push-changes.outputs.branch }}"
           REPO="${{ github.repository }}"
           SERVER="${{ github.server_url }}"
           RUN_URL="${SERVER}/${REPO}/actions/runs/${{ github.run_id }}"
-          TS_REF_URL="${SERVER}/${TS_REPO}/tree/${TS_REF}"
 
-          TITLE="[typespec-python] Regenerate tests from ${TS_REPO}@${TS_REF}"
+          # Use a stable source identifier so retriggering from the same `main`
+          # or the same PR reuses the existing tracking issue instead of
+          # creating a duplicate.
+          if [ -n "$PR_NUMBER" ]; then
+            SOURCE_LABEL="microsoft/typespec PR #${PR_NUMBER}"
+          else
+            SOURCE_LABEL="microsoft/typespec@main"
+          fi
+
+          TITLE="[typespec-python] Regenerate tests from ${SOURCE_LABEL}"
 
           # Build a "compare" URL that opens the PR creation page pre-filled.
           # GitHub Actions cannot create PRs directly (org policy), so the
           # reviewer just needs to click the link to open the PR.
           PR_TITLE_ENC=$(jq -rn --arg t "$TITLE" '$t|@uri')
-          PR_BODY_RAW="Automated regeneration of TypeSpec Python generated tests.
+          PR_BODY_RAW="Source: ${TS_REF_URL}
+
+          Automated regeneration of TypeSpec Python generated tests from ${SOURCE_LABEL}.
 
-          - Source: \`${TS_REPO}@${TS_REF}\` (${TS_REF_URL})
           - Workflow run: ${RUN_URL}
 
           This PR was auto-generated."
@@ -160,9 +207,9 @@ jobs:
           👉 [Create pull request from \`${BRANCH}\`](${COMPARE_URL})
 
           Details:
-          - Source: [\`${TS_REPO}@${TS_REF}\`](${TS_REF_URL})
+          - Source: [${SOURCE_LABEL}](${TS_REF_URL})
           - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
-          - Workflow run: ${RUN_URL}
+          - Latest workflow run: ${RUN_URL}
 
           cc @iscai-msft @msyyc"
 

From c9e9befd874caa9a79773a353dc58675e8c2f5e9 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 03:26:07 +0000
Subject: [PATCH 09/18] update issue title and body

---
 .../workflows/typespec-python-regenerate.yml  | 59 +++++++++++++------
 1 file changed, 41 insertions(+), 18 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 29bf96a8bedd..59d769509d5a 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -186,32 +186,55 @@ jobs:
 
           TITLE="[typespec-python] Regenerate tests from ${SOURCE_LABEL}"
 
-          # Build a "compare" URL that opens the PR creation page pre-filled.
-          # GitHub Actions cannot create PRs directly (org policy), so the
-          # reviewer just needs to click the link to open the PR.
-          PR_TITLE_ENC=$(jq -rn --arg t "$TITLE" '$t|@uri')
-          PR_BODY_RAW="Source: ${TS_REF_URL}
+          # Check whether an open PR already exists from this branch to main.
+          # If so, the tracking issue should just point at that PR instead of
+          # asking the user to create a new one.
+          EXISTING_PR_JSON=$(gh pr list --state open --head "$BRANCH" --base main \
+            --json number,url --limit 1)
+          EXISTING_PR_URL=$(echo "$EXISTING_PR_JSON" | jq -r '.[0].url // empty')
+          EXISTING_PR_NUMBER=$(echo "$EXISTING_PR_JSON" | jq -r '.[0].number // empty')
 
-          Automated regeneration of TypeSpec Python generated tests from ${SOURCE_LABEL}.
+          if [ -n "$EXISTING_PR_URL" ]; then
+            ISSUE_BODY="A pull request already exists for this regeneration.
 
-          - Workflow run: ${RUN_URL}
+            👉 [View pull request #${EXISTING_PR_NUMBER}](${EXISTING_PR_URL})
 
-          This PR was auto-generated."
-          PR_BODY_ENC=$(jq -rn --arg b "$PR_BODY_RAW" '$b|@uri')
-          COMPARE_URL="${SERVER}/${REPO}/compare/main...${BRANCH}?quick_pull=1&title=${PR_TITLE_ENC}&body=${PR_BODY_ENC}"
+            The branch \`${BRANCH}\` was just updated with the latest regenerated tests; the existing PR will reflect those changes automatically.
 
-          ISSUE_BODY="GitHub Actions is not permitted to create pull requests in this repository, so this issue tracks the regeneration instead.
+            Details:
+            - Source: [${SOURCE_LABEL}](${TS_REF_URL})
+            - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
+            - Latest workflow run: ${RUN_URL}
 
-          **Click the link below to open a pre-filled PR:**
+            cc @iscai-msft @msyyc"
+          else
+            # Build a "compare" URL that opens the PR creation page pre-filled.
+            # GitHub Actions cannot create PRs directly (org policy), so the
+            # reviewer just needs to click the link to open the PR.
+            PR_TITLE_ENC=$(jq -rn --arg t "$TITLE" '$t|@uri')
+            PR_BODY_RAW="Source: ${TS_REF_URL}
+
+            Automated regeneration of TypeSpec Python generated tests from ${SOURCE_LABEL}.
+
+            - Workflow run: ${RUN_URL}
+
+            This PR was auto-generated."
+            PR_BODY_ENC=$(jq -rn --arg b "$PR_BODY_RAW" '$b|@uri')
+            COMPARE_URL="${SERVER}/${REPO}/compare/main...${BRANCH}?quick_pull=1&title=${PR_TITLE_ENC}&body=${PR_BODY_ENC}"
 
-          👉 [Create pull request from \`${BRANCH}\`](${COMPARE_URL})
+            ISSUE_BODY="GitHub Actions is not permitted to create pull requests in this repository, so this issue tracks the regeneration instead.
 
-          Details:
-          - Source: [${SOURCE_LABEL}](${TS_REF_URL})
-          - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
-          - Latest workflow run: ${RUN_URL}
+            **Click the link below to open a pre-filled PR:**
 
-          cc @iscai-msft @msyyc"
+            👉 [Create pull request from \`${BRANCH}\`](${COMPARE_URL})
+
+            Details:
+            - Source: [${SOURCE_LABEL}](${TS_REF_URL})
+            - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
+            - Latest workflow run: ${RUN_URL}
+
+            cc @iscai-msft @msyyc"
+          fi
 
           # Reuse an existing open tracking issue if one exists (matched by title).
           EXISTING_ISSUE=$(gh issue list --state open --search "\"$TITLE\" in:title" \

From 318af5441d01f249352d81c2ce79c0dc81018627 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 03:29:05 +0000
Subject: [PATCH 10/18] udpate assignee

---
 .../workflows/typespec-python-regenerate.yml  | 21 +++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 59d769509d5a..4f3a641af5da 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -184,6 +184,19 @@ jobs:
             SOURCE_LABEL="microsoft/typespec@main"
           fi
 
+          # Determine assignees. For manual (workflow_dispatch) triggers,
+          # assign to the user who triggered the run. For automatic triggers
+          # (push), fall back to the default maintainers.
+          EVENT_NAME="${{ github.event_name }}"
+          ACTOR="${{ github.actor }}"
+          if [ "$EVENT_NAME" = "workflow_dispatch" ] && [ -n "$ACTOR" ]; then
+            ASSIGNEES="$ACTOR"
+            CC_LINE="cc @${ACTOR}"
+          else
+            ASSIGNEES="iscai-msft,msyyc"
+            CC_LINE="cc @iscai-msft @msyyc"
+          fi
+
           TITLE="[typespec-python] Regenerate tests from ${SOURCE_LABEL}"
 
           # Check whether an open PR already exists from this branch to main.
@@ -206,7 +219,7 @@ jobs:
             - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
             - Latest workflow run: ${RUN_URL}
 
-            cc @iscai-msft @msyyc"
+            ${CC_LINE}"
           else
             # Build a "compare" URL that opens the PR creation page pre-filled.
             # GitHub Actions cannot create PRs directly (org policy), so the
@@ -233,7 +246,7 @@ jobs:
             - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
             - Latest workflow run: ${RUN_URL}
 
-            cc @iscai-msft @msyyc"
+            ${CC_LINE}"
           fi
 
           # Reuse an existing open tracking issue if one exists (matched by title).
@@ -245,13 +258,13 @@ jobs:
             # Re-apply expected label and assignees in case they were removed from the existing issue.
             gh issue edit "$EXISTING_ISSUE" --body "$ISSUE_BODY" \
               --add-label "typespec-python" \
-              --add-assignee iscai-msft,msyyc
+              --add-assignee "$ASSIGNEES"
             ISSUE_NUMBER="$EXISTING_ISSUE"
           else
             echo "Creating new tracking issue"
             ISSUE_NUMBER=$(gh issue create --title "$TITLE" --body "$ISSUE_BODY" \
               --label "typespec-python" \
-              --assignee iscai-msft,msyyc \
+              --assignee "$ASSIGNEES" \
               --json number --jq '.number')
             echo "Created issue #$ISSUE_NUMBER"
           fi

From dcb370a1af01396950b1e050cf4fff04fa85064d Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 03:37:32 +0000
Subject: [PATCH 11/18] add readme

---
 eng/tools/emitter/README.md | 48 +++++++++++++++++++++++++++++++++++--
 1 file changed, 46 insertions(+), 2 deletions(-)

diff --git a/eng/tools/emitter/README.md b/eng/tools/emitter/README.md
index de1831a5f768..16b7e04fa501 100644
--- a/eng/tools/emitter/README.md
+++ b/eng/tools/emitter/README.md
@@ -4,7 +4,51 @@ This directory holds files related to the TypeSpec Python emitter (`@azure-tools
 
 ## Contents
 
-- **`gen/`** — Auto-generated Python SDK test code produced by the emitter.
-  These files are regenerated automatically by the [typespec-python-regenerate](https://github.com/Azure/azure-sdk-for-python/blob/main/.github/workflows/typespec-python-regenerate.yml) workflow whenever the emitter version in `eng/emitter-package.json` is updated.
+- **`gen/`** — Auto-generated Python SDK test code (`gen/azure/` and `gen/unbranded/`) produced by the emitter.
+  These files are regenerated by the [typespec-python-regenerate](../../../.github/workflows/typespec-python-regenerate.yml) workflow.
 
 > **Do not edit files in `gen/` by hand.** They will be overwritten on the next regeneration.
+
+## Regeneration workflow
+
+The [`typespec-python-regenerate`](../../../.github/workflows/typespec-python-regenerate.yml) GitHub Actions workflow regenerates the contents of `gen/`.
+
+### Triggers
+
+- **Automatic (push)** — runs when [`eng/emitter-package.json`](../../emitter-package.json) is updated on `main`. The workflow checks out `microsoft/typespec@main` and regenerates from there.
+- **Manual (`workflow_dispatch`)** — runs from the Actions tab with one input:
+  - **`typespec_ref`** — either:
+    - `main` (default) — regenerate from `microsoft/typespec@main`, or
+    - a `microsoft/typespec` pull request URL (e.g. `https://github.com/microsoft/typespec/pull/1234`) — the workflow resolves the PR's head repo and SHA via `gh pr view` and checks out that exact commit (so unmerged PRs and fork branches work).
+
+  Any other value is rejected.
+
+### What the workflow does
+
+> **Note:** When triggering from a `microsoft/typespec` pull request URL, make sure the PR is up to date with its `main` branch first — click **Update branch** on the PR before running this workflow. Otherwise the regenerated output will be based on a stale base and may produce a confusing diff that mixes PR changes with unrelated drift from `main`.
+
+1. Checks out `azure-sdk-for-python` and the resolved `microsoft/typespec` source into `_typespec/`.
+2. Builds `_typespec/packages/http-client-python` and runs `npm run regenerate`.
+3. Copies the regenerated output into `eng/tools/emitter/gen/azure` and `eng/tools/emitter/gen/unbranded`.
+4. If anything changed, force-pushes the result to a branch:
+   - `auto/typespec-python-regenerate` when the source is `main`
+   - `auto/typespec-python-regenerate-<PR_NUMBER>` when the source is a PR URL
+5. Creates or updates a tracking issue (GitHub Actions cannot open PRs directly in this repo):
+   - **Title** uses a stable source label so retriggering from the same source reuses the existing open issue instead of creating a duplicate:
+     - `[typespec-python] Regenerate tests from microsoft/typespec@main`
+     - `[typespec-python] Regenerate tests from microsoft/typespec PR #<N>`
+   - **Body** behavior:
+     - If no open PR exists from the branch to `main`, the body contains a prefilled compare URL ("Create pull request from `<branch>`") that opens a PR with the title and body already populated.
+     - If an open PR already exists from the branch to `main`, the body links directly to that PR and notes that the existing PR has been updated with the new commit (a force-push does not close the PR).
+   - **Assignees / cc**:
+     - Manual (`workflow_dispatch`) runs are assigned to the user who triggered the run (`github.actor`).
+     - Automatic (`push`) runs are assigned to the default maintainers (`@iscai-msft`, `@msyyc`).
+
+
+### Failure notifications
+
+If the `regenerate` job fails, a separate `notify-on-failure` job opens a new issue titled `[typespec-python] Regeneration workflow failed`, labeled `typespec-python`, and always assigned to `@iscai-msft` and `@msyyc` regardless of trigger.
+
+### Concurrency
+
+The workflow uses `concurrency: { group: <workflow>, cancel-in-progress: true }`, so a newer run cancels any in-flight run.

From 59af2fc670337ba34b59763ffd8cbf476f4cda3e Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 03:49:25 +0000
Subject: [PATCH 12/18] add schedule

---
 .github/workflows/typespec-python-regenerate.yml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 4f3a641af5da..560d6b8e97c6 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -6,6 +6,9 @@ on:
     branches: [main]
     paths:
       - "eng/emitter-package.json"
+  # Run daily at 22:00 UTC against microsoft/typespec@main
+  schedule:
+    - cron: "0 22 * * *"
   # Allow manual triggering
   workflow_dispatch:
     inputs:

From aab3256ee0820970d6525afe5d9e27196a9a1200 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 05:06:16 +0000
Subject: [PATCH 13/18] update

---
 .../workflows/typespec-python-regenerate.yml  | 24 ++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 560d6b8e97c6..09af85a4c841 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -151,6 +151,8 @@ jobs:
           git config user.name "github-actions[bot]"
           git config user.email "github-actions[bot]@users.noreply.github.com"
 
+          # First, check whether regenerated content actually differs from what
+          # is already on disk (relative to the workflow's HEAD).
           git add eng/tools/emitter/gen/
           if git diff --cached --quiet; then
             echo "No changes to commit"
@@ -158,7 +160,27 @@ jobs:
             exit 0
           fi
 
-          git checkout -B "$BRANCH"
+          # Branch off origin/main (NOT the current HEAD) so the auto branch
+          # never contains unrelated commits from the branch that triggered
+          # the workflow. In particular this avoids carrying changes to
+          # .github/workflows/*, which GITHUB_TOKEN is not allowed to push
+          # (missing `workflows` permission).
+          git fetch --no-tags --depth=1 origin main
+          git checkout -B "$BRANCH" origin/main
+
+          # Re-apply just the regenerated gen/ tree on top of origin/main.
+          # HEAD@{1} is the workflow's original HEAD before the checkout above.
+          git checkout HEAD@{1} -- eng/tools/emitter/gen
+          git add eng/tools/emitter/gen/
+
+          # If origin/main already matches the regenerated output, there is
+          # nothing to push.
+          if git diff --cached --quiet; then
+            echo "No changes vs origin/main"
+            echo "has_changes=false" >> $GITHUB_OUTPUT
+            exit 0
+          fi
+
           git commit -m "[typespec-python] Regenerate tests from ${SOURCE_LABEL}"
           git push origin "$BRANCH" --force
           echo "has_changes=true" >> $GITHUB_OUTPUT

From 07622bbb58347c1ce86b32d1e837286a4252da53 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 05:56:17 +0000
Subject: [PATCH 14/18] update

---
 .github/workflows/typespec-python-regenerate.yml | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 09af85a4c841..e5485a61a817 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -287,11 +287,14 @@ jobs:
             ISSUE_NUMBER="$EXISTING_ISSUE"
           else
             echo "Creating new tracking issue"
-            ISSUE_NUMBER=$(gh issue create --title "$TITLE" --body "$ISSUE_BODY" \
+            # `gh issue create` prints the new issue's URL to stdout; parse the
+            # trailing number out of it. (`--json`/`--jq` are not supported on
+            # `gh issue create`.)
+            ISSUE_URL=$(gh issue create --title "$TITLE" --body "$ISSUE_BODY" \
               --label "typespec-python" \
-              --assignee "$ASSIGNEES" \
-              --json number --jq '.number')
-            echo "Created issue #$ISSUE_NUMBER"
+              --assignee "$ASSIGNEES")
+            ISSUE_NUMBER="${ISSUE_URL##*/}"
+            echo "Created issue #$ISSUE_NUMBER ($ISSUE_URL)"
           fi
           echo "issue_number=$ISSUE_NUMBER" >> $GITHUB_OUTPUT
 

From a1f06242e7e8838f18dd7b2b487e8f3988edc20d Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 06:01:38 +0000
Subject: [PATCH 15/18] update

---
 .../workflows/typespec-python-regenerate.yml  | 43 ++++++++++++++-----
 1 file changed, 33 insertions(+), 10 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index e5485a61a817..e3ca24797f24 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -310,14 +310,37 @@ jobs:
         with:
           script: |
             const runUrl = `${context.serverUrl}/${context.repo.owner}/${context.repo.repo}/actions/runs/${context.runId}`;
-            await github.rest.issues.create({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              title: '[typespec-python] Regeneration workflow failed',
-              body: `The TypeSpec Python test regeneration workflow failed.\n\n` +
-                    `- **Run:** ${runUrl}\n` +
-                    `- **Trigger:** ${context.eventName}\n\n` +
-                    `cc @iscai-msft @msyyc`,
-              labels: ['typespec-python'],
-              assignees: ['iscai-msft', 'msyyc']
+            const title = '[typespec-python] Regeneration workflow failed';
+            const body = `The TypeSpec Python test regeneration workflow failed.\n\n` +
+                         `- **Run:** ${runUrl}\n` +
+                         `- **Trigger:** ${context.eventName}\n\n` +
+                         `cc @iscai-msft @msyyc`;
+
+            // Look for an existing open issue with the same title; if found,
+            // add a comment instead of creating a duplicate.
+            const existing = await github.rest.search.issuesAndPullRequests({
+              q: `repo:${context.repo.owner}/${context.repo.repo} is:issue is:open in:title "${title}"`,
             });
+            const match = existing.data.items.find(
+              (i) => i.title === title && !i.pull_request,
+            );
+
+            if (match) {
+              core.info(`Commenting on existing issue #${match.number}`);
+              await github.rest.issues.createComment({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: match.number,
+                body,
+              });
+            } else {
+              core.info('Creating new failure-notification issue');
+              await github.rest.issues.create({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                title,
+                body,
+                labels: ['typespec-python'],
+                assignees: ['iscai-msft', 'msyyc'],
+              });
+            }

From c4761909214d76287b4802b5f4dadee665c36cc5 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 07:18:55 +0000
Subject: [PATCH 16/18] replace readme with template

---
 .../workflows/typespec-python-regenerate.yml    | 17 +++++++++++++++++
 eng/tools/emitter/gen/template/README.md        |  3 +++
 2 files changed, 20 insertions(+)
 create mode 100644 eng/tools/emitter/gen/template/README.md

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index e3ca24797f24..c9a213da275c 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -136,6 +136,23 @@ jobs:
       - name: Clean up typespec checkout
         run: rm -rf "_typespec"
 
+      - name: Apply README template to generated test packages
+        run: |
+          set -euo pipefail
+          TARGET="eng/tools/emitter/gen"
+          TEMPLATE="$TARGET/template/README.md"
+          if [ ! -f "$TEMPLATE" ]; then
+            echo "::error::Template README not found at $TEMPLATE"
+            exit 1
+          fi
+          # Replace every README.md under gen/ with the template, except:
+          #   - the top-level gen/README.md
+          #   - the template itself (gen/template/README.md)
+          find "$TARGET" -type f -name README.md \
+            ! -path "$TARGET/README.md" \
+            ! -path "$TEMPLATE" \
+            -print -exec cp -f "$TEMPLATE" {} \;
+
       - name: Commit and push changes
         id: push-changes
         run: |
diff --git a/eng/tools/emitter/gen/template/README.md b/eng/tools/emitter/gen/template/README.md
new file mode 100644
index 000000000000..e168787b1af1
--- /dev/null
+++ b/eng/tools/emitter/gen/template/README.md
@@ -0,0 +1,3 @@
+# ⚠️ TEST CODE — DO NOT INSTALL FROM PYPI
+
+This is not a published Azure SDK package; it exists only for testing purposes. Do not install from PyPI.

From 2606527cfacf099b82ef5711dce1e120b36bc5f0 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 08:03:23 +0000
Subject: [PATCH 17/18] udpate

---
 .../workflows/typespec-python-regenerate.yml  | 56 +++++++++++--------
 1 file changed, 33 insertions(+), 23 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index c9a213da275c..7ca6937748c4 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -241,6 +241,30 @@ jobs:
 
           TITLE="[typespec-python] Regenerate tests from ${SOURCE_LABEL}"
 
+          # Reuse an existing open tracking issue if one exists (matched by
+          # title). We resolve the issue number BEFORE building the PR compare
+          # URL so we can inject "Fixes #<N>" into the prefilled PR body — this
+          # way the issue is closed automatically when the PR is merged.
+          EXISTING_ISSUE=$(gh issue list --state open --search "\"$TITLE\" in:title" \
+            --json number,title | jq -r --arg title "$TITLE" '.[] | select(.title == $title) | .number' | head -n1 || echo "")
+
+          if [ -n "$EXISTING_ISSUE" ]; then
+            ISSUE_NUMBER="$EXISTING_ISSUE"
+            echo "Reusing existing tracking issue #$ISSUE_NUMBER"
+          else
+            echo "Creating new tracking issue"
+            # `gh issue create` prints the new issue's URL to stdout; parse the
+            # trailing number out of it. (`--json`/`--jq` are not supported on
+            # `gh issue create`.) The body will be filled in below once we
+            # have the compare URL.
+            ISSUE_URL=$(gh issue create --title "$TITLE" \
+              --body "Tracking issue for TypeSpec Python regeneration. Details will be filled in shortly." \
+              --label "typespec-python" \
+              --assignee "$ASSIGNEES")
+            ISSUE_NUMBER="${ISSUE_URL##*/}"
+            echo "Created issue #$ISSUE_NUMBER ($ISSUE_URL)"
+          fi
+
           # Check whether an open PR already exists from this branch to main.
           # If so, the tracking issue should just point at that PR instead of
           # asking the user to create a new one.
@@ -266,8 +290,11 @@ jobs:
             # Build a "compare" URL that opens the PR creation page pre-filled.
             # GitHub Actions cannot create PRs directly (org policy), so the
             # reviewer just needs to click the link to open the PR.
+            ISSUE_LINK="${SERVER}/${REPO}/issues/${ISSUE_NUMBER}"
             PR_TITLE_ENC=$(jq -rn --arg t "$TITLE" '$t|@uri')
-            PR_BODY_RAW="Source: ${TS_REF_URL}
+            PR_BODY_RAW="Fixes ${ISSUE_LINK}
+
+            Source: ${TS_REF_URL}
 
             Automated regeneration of TypeSpec Python generated tests from ${SOURCE_LABEL}.
 
@@ -291,28 +318,11 @@ jobs:
             ${CC_LINE}"
           fi
 
-          # Reuse an existing open tracking issue if one exists (matched by title).
-          EXISTING_ISSUE=$(gh issue list --state open --search "\"$TITLE\" in:title" \
-            --json number,title | jq -r --arg title "$TITLE" '.[] | select(.title == $title) | .number' | head -n1 || echo "")
-
-          if [ -n "$EXISTING_ISSUE" ]; then
-            echo "Updating existing issue #$EXISTING_ISSUE"
-            # Re-apply expected label and assignees in case they were removed from the existing issue.
-            gh issue edit "$EXISTING_ISSUE" --body "$ISSUE_BODY" \
-              --add-label "typespec-python" \
-              --add-assignee "$ASSIGNEES"
-            ISSUE_NUMBER="$EXISTING_ISSUE"
-          else
-            echo "Creating new tracking issue"
-            # `gh issue create` prints the new issue's URL to stdout; parse the
-            # trailing number out of it. (`--json`/`--jq` are not supported on
-            # `gh issue create`.)
-            ISSUE_URL=$(gh issue create --title "$TITLE" --body "$ISSUE_BODY" \
-              --label "typespec-python" \
-              --assignee "$ASSIGNEES")
-            ISSUE_NUMBER="${ISSUE_URL##*/}"
-            echo "Created issue #$ISSUE_NUMBER ($ISSUE_URL)"
-          fi
+          # Write the final body onto the tracking issue (whether reused or
+          # just created) and re-apply expected label and assignees.
+          gh issue edit "$ISSUE_NUMBER" --body "$ISSUE_BODY" \
+            --add-label "typespec-python" \
+            --add-assignee "$ASSIGNEES"
           echo "issue_number=$ISSUE_NUMBER" >> $GITHUB_OUTPUT
 
   notify-on-failure:

From 5ee52c4ddf3f602dd279cebf9df68b9001f79a28 Mon Sep 17 00:00:00 2001
From: Yuchao Yan <yuchaoyan@microsoft.com>
Date: Thu, 14 May 2026 08:32:05 +0000
Subject: [PATCH 18/18] review

---
 .../workflows/typespec-python-regenerate.yml  | 63 +++++++++++--------
 eng/tools/emitter/README.md                   |  4 +-
 2 files changed, 41 insertions(+), 26 deletions(-)

diff --git a/.github/workflows/typespec-python-regenerate.yml b/.github/workflows/typespec-python-regenerate.yml
index 7ca6937748c4..06aaecf79f2b 100644
--- a/.github/workflows/typespec-python-regenerate.yml
+++ b/.github/workflows/typespec-python-regenerate.yml
@@ -22,6 +22,10 @@ permissions:
   pull-requests: write
   issues: write
 
+# Note: with cancel-in-progress, a newer run can cancel an older one after it
+# has force-pushed the branch but before it finishes updating the tracking
+# issue. The newer run will redo the issue update, so the worst case is a
+# brief stale issue body that is immediately refreshed.
 concurrency:
   group: ${{ github.workflow }}
   cancel-in-progress: true
@@ -147,10 +151,11 @@ jobs:
           fi
           # Replace every README.md under gen/ with the template, except:
           #   - the top-level gen/README.md
-          #   - the template itself (gen/template/README.md)
+          #   - anything under gen/template/ (the template itself and any
+          #     future siblings)
           find "$TARGET" -type f -name README.md \
             ! -path "$TARGET/README.md" \
-            ! -path "$TEMPLATE" \
+            ! -path "$TARGET/template/*" \
             -print -exec cp -f "$TEMPLATE" {} \;
 
       - name: Commit and push changes
@@ -242,11 +247,19 @@ jobs:
           TITLE="[typespec-python] Regenerate tests from ${SOURCE_LABEL}"
 
           # Reuse an existing open tracking issue if one exists (matched by
-          # title). We resolve the issue number BEFORE building the PR compare
-          # URL so we can inject "Fixes #<N>" into the prefilled PR body — this
-          # way the issue is closed automatically when the PR is merged.
-          EXISTING_ISSUE=$(gh issue list --state open --search "\"$TITLE\" in:title" \
-            --json number,title | jq -r --arg title "$TITLE" '.[] | select(.title == $title) | .number' | head -n1 || echo "")
+          # exact title). We resolve the issue number BEFORE building the PR
+          # compare URL so we can inject "Fixes #<N>" into the prefilled PR
+          # body — this way the issue is closed automatically when the PR is
+          # merged.
+          #
+          # We list by label rather than `--search`, because GitHub's search
+          # tokenizer strips characters like `[`, `]`, `@`, `#` and `/`, so a
+          # search query over our title can be ambiguous. Listing by label
+          # plus an exact jq match is both faster and unambiguous.
+          EXISTING_ISSUE=$(gh issue list --state open --label typespec-python \
+            --limit 100 --json number,title \
+            | jq -r --arg title "$TITLE" '.[] | select(.title == $title) | .number' \
+            | head -n1 || echo "")
 
           if [ -n "$EXISTING_ISSUE" ]; then
             ISSUE_NUMBER="$EXISTING_ISSUE"
@@ -276,16 +289,16 @@ jobs:
           if [ -n "$EXISTING_PR_URL" ]; then
             ISSUE_BODY="A pull request already exists for this regeneration.
 
-            👉 [View pull request #${EXISTING_PR_NUMBER}](${EXISTING_PR_URL})
+          👉 [View pull request #${EXISTING_PR_NUMBER}](${EXISTING_PR_URL})
 
-            The branch \`${BRANCH}\` was just updated with the latest regenerated tests; the existing PR will reflect those changes automatically.
+          The branch \`${BRANCH}\` was just updated with the latest regenerated tests; the existing PR will reflect those changes automatically.
 
-            Details:
-            - Source: [${SOURCE_LABEL}](${TS_REF_URL})
-            - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
-            - Latest workflow run: ${RUN_URL}
+          Details:
+          - Source: [${SOURCE_LABEL}](${TS_REF_URL})
+          - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
+          - Latest workflow run: ${RUN_URL}
 
-            ${CC_LINE}"
+          ${CC_LINE}"
           else
             # Build a "compare" URL that opens the PR creation page pre-filled.
             # GitHub Actions cannot create PRs directly (org policy), so the
@@ -294,28 +307,28 @@ jobs:
             PR_TITLE_ENC=$(jq -rn --arg t "$TITLE" '$t|@uri')
             PR_BODY_RAW="Fixes ${ISSUE_LINK}
 
-            Source: ${TS_REF_URL}
+          Source: ${TS_REF_URL}
 
-            Automated regeneration of TypeSpec Python generated tests from ${SOURCE_LABEL}.
+          Automated regeneration of TypeSpec Python generated tests from ${SOURCE_LABEL}.
 
-            - Workflow run: ${RUN_URL}
+          - Workflow run: ${RUN_URL}
 
-            This PR was auto-generated."
+          This PR was auto-generated."
             PR_BODY_ENC=$(jq -rn --arg b "$PR_BODY_RAW" '$b|@uri')
             COMPARE_URL="${SERVER}/${REPO}/compare/main...${BRANCH}?quick_pull=1&title=${PR_TITLE_ENC}&body=${PR_BODY_ENC}"
 
             ISSUE_BODY="GitHub Actions is not permitted to create pull requests in this repository, so this issue tracks the regeneration instead.
 
-            **Click the link below to open a pre-filled PR:**
+          **Click the link below to open a pre-filled PR:**
 
-            👉 [Create pull request from \`${BRANCH}\`](${COMPARE_URL})
+          👉 [Create pull request from \`${BRANCH}\`](${COMPARE_URL})
 
-            Details:
-            - Source: [${SOURCE_LABEL}](${TS_REF_URL})
-            - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
-            - Latest workflow run: ${RUN_URL}
+          Details:
+          - Source: [${SOURCE_LABEL}](${TS_REF_URL})
+          - Branch: [\`${BRANCH}\`](${SERVER}/${REPO}/tree/${BRANCH})
+          - Latest workflow run: ${RUN_URL}
 
-            ${CC_LINE}"
+          ${CC_LINE}"
           fi
 
           # Write the final body onto the tracking issue (whether reused or
diff --git a/eng/tools/emitter/README.md b/eng/tools/emitter/README.md
index 16b7e04fa501..43af61d1a72e 100644
--- a/eng/tools/emitter/README.md
+++ b/eng/tools/emitter/README.md
@@ -38,12 +38,14 @@ The [`typespec-python-regenerate`](../../../.github/workflows/typespec-python-re
      - `[typespec-python] Regenerate tests from microsoft/typespec@main`
      - `[typespec-python] Regenerate tests from microsoft/typespec PR #<N>`
    - **Body** behavior:
-     - If no open PR exists from the branch to `main`, the body contains a prefilled compare URL ("Create pull request from `<branch>`") that opens a PR with the title and body already populated.
+     - If no open PR exists from the branch to `main`, the body contains a prefilled compare URL ("Create pull request from `<branch>`") that opens a PR with the title and body already populated. The prefilled PR body starts with `Fixes <issue URL>` so the tracking issue is closed automatically when the PR is merged.
      - If an open PR already exists from the branch to `main`, the body links directly to that PR and notes that the existing PR has been updated with the new commit (a force-push does not close the PR).
    - **Assignees / cc**:
      - Manual (`workflow_dispatch`) runs are assigned to the user who triggered the run (`github.actor`).
      - Automatic (`push`) runs are assigned to the default maintainers (`@iscai-msft`, `@msyyc`).
 
+> **Note:** The auto branch is **force-pushed** on every run. If a reviewer has the compare link open and no PR has been created yet, the diff under that link will change when the next run pushes — they should reopen the link from the tracking issue to see the latest diff. If a PR already exists, the force-push updates the PR in place (it does not close it; review comments on lines that no longer exist become "outdated").
+
 
 ### Failure notifications