feat: add PR intent labeling workflow

.github/workflows/contributor-check.yml

@@ -19,6 +19,11 @@ jobs:
       github.actor != 'github-actions[bot]' &&
       github.actor != 'copilot-swe-agent[bot]'
     steps:
+      - name: Checkout code
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
+        with:
+          fetch-depth: 0
+
       - name: Setup Python
         uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
         with:

.github/workflows/label-pr-intent.yml

@@ -0,0 +1,241 @@
+name: Label PR Intent
+
+on:
+  pull_request_target:
+    types: [opened, synchronize, reopened, edited, ready_for_review]
+
+permissions:
+  issues: write
+  pull-requests: read
+
+jobs:
+  label-pr:
+    runs-on: ubuntu-latest
+    if: >-
+      github.actor != 'dependabot[bot]' &&
+      github.actor != 'github-actions[bot]'
+    steps:
+      - name: Apply intent labels
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7.1.0
+        with:
+          script: |
+            const managedLabels = {
+              'targets-main': {
+                color: 'B60205',
+                description: 'PR targets main instead of staged'
+              },
+              'branched-main': {
+                color: 'D93F0B',
+                description: 'PR appears to include plugin files materialized from main'
+              },
+              'skills': {
+                color: '1D76DB',
+                description: 'PR touches skills'
+              },
+              'plugin': {
+                color: '5319E7',
+                description: 'PR touches plugins'
+              },
+              'agent': {
+                color: '0E8A16',
+                description: 'PR touches agents'
+              },
+              'instructions': {
+                color: 'FBCA04',
+                description: 'PR touches instructions'
+              },
+              'new-submission': {
+                color: '006B75',
+                description: 'PR adds at least one new contribution'
+              },
+              'website-update': {
+                color: '0052CC',
+                description: 'PR touches website content or code'
+              },
+              'external-plugin': {
+                color: 'FEF2C0',
+                description: 'PR updates plugins/external.json'
+              },
+              'hooks': {
+                color: 'C2E0C6',
+                description: 'PR touches hooks'
+              },
+              'workflow': {
+                color: 'BFD4F2',
+                description: 'PR touches workflow automation'
+              }
+            };
+
+            const matchesAny = (filename, patterns) => patterns.some((pattern) => pattern.test(filename));
+
+            async function listAllFiles() {
+              const files = [];
+              let page = 1;
+
+              while (true) {
+                const response = await github.rest.pulls.listFiles({
+                  owner: context.repo.owner,
+                  repo: context.repo.repo,
+                  pull_number: context.issue.number,
+                  per_page: 100,
+                  page
+                });
+
+                files.push(...response.data);
+
+                if (response.data.length < 100) {
+                  return files;
+                }
+
+                page += 1;
+              }
+            }
+
+            async function ensureLabel(name, { color, description }) {
+              try {
+                await github.rest.issues.createLabel({
+                  owner: context.repo.owner,
+                  repo: context.repo.repo,
+                  name,
+                  color,
+                  description
+                });
+              } catch (error) {
+                if (error.status !== 422) {
+                  throw error;
+                }
+              }
+            }
+
+            const files = await listAllFiles();
+            const filenames = files.map((file) => file.filename);
+
+            const patterns = {
+              branchedMain: [
+                /^plugins\/[^/]+\/(?:agents|commands|skills)\//
+              ],
+              skills: [
+                /^skills\//
+              ],
+              plugin: [
+                /^plugins\//
+              ],
+              agent: [
+                /^agents\/.+\.agent\.md$/
+              ],
+              instructions: [
+                /^instructions\/.+\.instructions\.md$/
+              ],
+              websiteUpdate: [
+                /^website\//
+              ],
+              externalPlugin: [
+                /^plugins\/external\.json$/
+              ],
+              hooks: [
+                /^hooks\//
+              ],
+              workflow: [
+                /^workflows\/.+\.md$/,
+                /^\.github\/workflows\/.+\.(?:ya?ml|md)$/
+              ],
+              newSubmission: [
+                /^agents\/.+\.agent\.md$/,
+                /^instructions\/.+\.instructions\.md$/,
+                /^skills\/[^/]+\/SKILL\.md$/,
+                /^hooks\/[^/]+\/(?:README\.md|hooks\.json)$/,
+                /^plugins\/[^/]+\/\.github\/plugin\/plugin\.json$/,
+                /^workflows\/.+\.md$/,
+                /^\.github\/workflows\/.+\.(?:ya?ml|md)$/,
+                /^website\//
+              ]
+            };
+
+            const isBranchedMain = filenames.some((filename) => matchesAny(filename, patterns.branchedMain));
+            const hasNewSubmission = files.some(
+              (file) => file.status === 'added' && matchesAny(file.filename, patterns.newSubmission)
+            );
+
+            const desiredLabels = new Set();
+
+            if (context.payload.pull_request.base.ref === 'main') {
+              desiredLabels.add('targets-main');
+            }
+
+            if (filenames.some((filename) => matchesAny(filename, patterns.externalPlugin))) {
+              desiredLabels.add('external-plugin');
+            }
+
+            if (isBranchedMain) {
+              desiredLabels.add('branched-main');
+            } else {
+              if (filenames.some((filename) => matchesAny(filename, patterns.skills))) {
+                desiredLabels.add('skills');
+              }
+
+              if (filenames.some((filename) => matchesAny(filename, patterns.plugin))) {
+                desiredLabels.add('plugin');
+              }
+
+              if (filenames.some((filename) => matchesAny(filename, patterns.agent))) {
+                desiredLabels.add('agent');
+              }
+
+              if (filenames.some((filename) => matchesAny(filename, patterns.instructions))) {
+                desiredLabels.add('instructions');
+              }
+
+              if (filenames.some((filename) => matchesAny(filename, patterns.websiteUpdate))) {
+                desiredLabels.add('website-update');
+              }
+
+              if (filenames.some((filename) => matchesAny(filename, patterns.hooks))) {
+                desiredLabels.add('hooks');
+              }
+
+              if (filenames.some((filename) => matchesAny(filename, patterns.workflow))) {
+                desiredLabels.add('workflow');
+              }
+
+              if (hasNewSubmission) {
+                desiredLabels.add('new-submission');
+              }
+            }
+
+            await Promise.all(
+              Object.entries(managedLabels).map(([name, config]) => ensureLabel(name, config))
+            );
+
+            const currentLabels = await github.paginate(github.rest.issues.listLabelsOnIssue, {
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: context.issue.number,
+              per_page: 100
+            });
+
+            const currentManagedLabels = currentLabels
+              .map((label) => label.name)
+              .filter((name) => Object.prototype.hasOwnProperty.call(managedLabels, name));
+
+            const labelsToAdd = [...desiredLabels].filter((name) => !currentManagedLabels.includes(name));
+            const labelsToRemove = currentManagedLabels.filter((name) => !desiredLabels.has(name));
+
+            if (labelsToAdd.length > 0) {
+              await github.rest.issues.addLabels({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                labels: labelsToAdd
+              });
+            }
+
+            for (const name of labelsToRemove) {
+              await github.rest.issues.removeLabel({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                name
+              });
+            }
+
+            core.info(`Managed labels: ${[...desiredLabels].sort().join(', ') || 'none'}`);