Nightly report: post details as follow-up comments instead of truncating (#1239)

When the full report exceeds GitHub's 65K body limit, the summary
table stays in the discussion/issue body and the verbose skill/agent
output is posted as follow-up comments (split into chunks if needed).
This ensures no output is lost.

.github/workflows/skill-quality-report.yml

@@ -206,94 +206,96 @@ jobs:
 
             const title = `Skill Quality Report — ${today}`;
 
-            const body = [
+            const annotatedSkills = annotateWithAuthors(skillsOutput, 'skill');
-              `# ${title}`,
+            const annotatedAgents = annotateWithAuthors(agentsOutput, 'agent');
-              '',
+
-              `**${skillDirs.length} skills** and **${agentFiles.length} agents** scanned.`,
+            // ── Body size management ──────────────────────────────
-              '',
+            // GitHub body limit is ~65536 UTF-8 bytes for both
-              `| Severity | Count |`,
+            // Discussions and Issues. When the full report fits, we
-              `|----------|-------|`,
+            // inline everything. When it doesn't, the body gets a
+            // compact summary and the verbose sections are written to
+            // separate files that get posted as follow-up comments.
+            const MAX_BYTES = 65000; // leave margin
+
+            function makeDetailsBlock(heading, summary, content) {
+              return [
+                `## ${heading}`, '',
+                '<details>',
+                `<summary>${summary}</summary>`, '',
+                '```', content, '```', '',
+                '</details>',
+              ].join('\n');
+            }
+
+            const summaryLines = [
+              `# ${title}`, '',
+              `**${skillDirs.length} skills** and **${agentFiles.length} agents** scanned.`, '',
+              '| Severity | Count |',
+              '|----------|-------|',
               `| ⛔ Errors | ${errorCount} |`,
               `| ⚠️ Warnings | ${warningCount} |`,
-              `| ℹ️ Advisories | ${advisoryCount} |`,
+              `| ℹ️ Advisories | ${advisoryCount} |`, '',
-              '',
               '---',
-              '',
+            ];
-              '## Skills',
+            const footer = `\n---\n\n_Generated by the [Skill Validator nightly scan](https://github.com/${context.repo.owner}/${context.repo.repo}/actions/workflows/skill-quality-report.yml)._`;
-              '',
+
-              '<details>',
+            const skillsBlock = makeDetailsBlock('Skills', 'Full skill-validator output for skills', annotatedSkills);
-              '<summary>Full skill-validator output for skills</summary>',
+            const agentsBlock = makeDetailsBlock('Agents', 'Full skill-validator output for agents', annotatedAgents);
-              '',
+
-              '```',
+            // Try full inline body first
-              annotateWithAuthors(skillsOutput, 'skill'),
+            const fullBody = summaryLines.join('\n') + '\n\n' + skillsBlock + '\n\n' + agentsBlock + footer;
-              '```',
+
-              '',
+            const commentParts = []; // overflow comment files
-              '</details>',
+
-              '',
+            let finalBody;
-              '## Agents',
+            if (Buffer.byteLength(fullBody, 'utf8') <= MAX_BYTES) {
-              '',
+              finalBody = fullBody;
-              '<details>',
+            } else {
-              '<summary>Full skill-validator output for agents</summary>',
+              // Details won't fit inline — move them to follow-up comments
-              '',
+              const bodyNote = '\n\n> **Note:** Detailed output is posted in the comments below (too large for the discussion body).\n';
-              '```',
+              finalBody = summaryLines.join('\n') + bodyNote + footer;
-              annotateWithAuthors(agentsOutput, 'agent'),
+
-              '```',
+              // Split each section into ≤65 KB chunks
-              '',
+              function chunkContent(label, content) {
-              '</details>',
+                const prefix = `## ${label}\n\n\`\`\`\n`;
-              '',
+                const suffix = '\n```';
-              '---',
+                const overhead = Buffer.byteLength(prefix + suffix, 'utf8');
-              '',
+                const budget = MAX_BYTES - overhead;
-              `_Generated by the [Skill Validator nightly scan](https://github.com/${context.repo.owner}/${context.repo.repo}/actions/workflows/skill-quality-report.yml)._`,
+
-            ].join('\n');
+                const buf = Buffer.from(content, 'utf8');
+                if (buf.length <= budget) {
+                  return [prefix + content + suffix];
+                }
+                const parts = [];
+                let offset = 0;
+                let partNum = 1;
+                while (offset < buf.length) {
+                  const slice = buf.slice(offset, offset + budget).toString('utf8');
+                  // Remove trailing replacement char from mid-codepoint cut
+                  const clean = slice.replace(/\uFFFD$/, '');
+                  const hdr = `## ${label} (part ${partNum})\n\n\`\`\`\n`;
+                  parts.push(hdr + clean + suffix);
+                  offset += Buffer.byteLength(clean, 'utf8');
+                  partNum++;
+                }
+                return parts;
+              }
+
+              commentParts.push(...chunkContent('Skills', annotatedSkills));
+              commentParts.push(...chunkContent('Agents', annotatedAgents));
+            }
 
             core.setOutput('title', title);
             core.setOutput('body_file', 'report-body.md');
 
-            // GitHub Issues/Discussions enforce a body size limit on the
-            // UTF-8 payload (~65536 bytes). Use byte-based limits and prefer
-            // shrinking verbose <details> sections to keep markdown valid.
-            const MAX_BODY_BYTES = 65000; // leave some margin
-
-            function shrinkDetailsSections(markdown) {
-              return markdown.replace(
-                /<details([\s\S]*?)>[\s\S]*?<\/details>/g,
-                (match, attrs) => {
-                  const placeholder = '\n<summary>Details truncated</summary>\n\n' +
-                    "> Full output was truncated to fit GitHub's body size limit. " +
-                    'See the workflow run for complete output.\n';
-                  return `<details${attrs}>${placeholder}</details>`;
-                }
-              );
-            }
-
-            function trimToByteLimit(str, maxBytes) {
-              const buf = Buffer.from(str, 'utf8');
-              if (buf.length <= maxBytes) return str;
-              // Slice bytes and decode, which safely handles multi-byte chars
-              return buf.slice(0, maxBytes).toString('utf8').replace(/\uFFFD$/, '');
-            }
-
-            const truncNote = '\n\n> **Note:** Output was truncated to fit GitHub\'s body size limit. See the [workflow run](https://github.com/' + context.repo.owner + '/' + context.repo.repo + '/actions/workflows/skill-quality-report.yml) for full output.\n';
-            const truncNoteBytes = Buffer.byteLength(truncNote, 'utf8');
-
-            let finalBody = body;
-
-            if (Buffer.byteLength(finalBody, 'utf8') > MAX_BODY_BYTES) {
-              // First try: collapse <details> sections to reduce size
-              finalBody = shrinkDetailsSections(finalBody);
-            }
-
-            if (Buffer.byteLength(finalBody, 'utf8') > MAX_BODY_BYTES) {
-              // Last resort: hard byte-trim + truncation note
-              finalBody = trimToByteLimit(finalBody, MAX_BODY_BYTES - truncNoteBytes);
-            }
-
-            if (Buffer.byteLength(finalBody, 'utf8') < Buffer.byteLength(body, 'utf8')) {
-              finalBody += truncNote;
-            }
-
             fs.writeFileSync('report-body.md', finalBody);
 
+            // Write overflow comment parts as numbered files
+            for (let i = 0; i < commentParts.length; i++) {
+              fs.writeFileSync(`report-comment-${i}.md`, commentParts[i]);
+            }
+            core.setOutput('comment_count', String(commentParts.length));
+
       # ── Create Discussion (preferred) or Issue (fallback) ────────
       - name: Create Discussion
         id: create-discussion
@@ -304,6 +306,7 @@ jobs:
             const fs = require('fs');
             const title = '${{ steps.report.outputs.title }}'.replace(/'/g, "\\'");
             const body = fs.readFileSync('report-body.md', 'utf8');
+            const commentCount = parseInt('${{ steps.report.outputs.comment_count }}' || '0', 10);
 
             // Find the "Skill Quality Reports" category
             const categoriesResult = await github.graphql(`
@@ -331,7 +334,7 @@ jobs:
               return;
             }
 
-            await github.graphql(`
+            const result = await github.graphql(`
               mutation($repoId: ID!, $categoryId: ID!, $title: String!, $body: String!) {
                 createDiscussion(input: {
                   repositoryId: $repoId,
@@ -339,7 +342,7 @@ jobs:
                   title: $title,
                   body: $body
                 }) {
-                  discussion { url }
+                  discussion { id url }
                 }
               }
             `, {
@@ -349,7 +352,24 @@ jobs:
               body: body,
             });
 
-            console.log('Discussion created successfully.');
+            const discussionId = result.createDiscussion.discussion.id;
+            console.log(`Discussion created: ${result.createDiscussion.discussion.url}`);
+
+            // Post overflow detail comments
+            for (let i = 0; i < commentCount; i++) {
+              const commentBody = fs.readFileSync(`report-comment-${i}.md`, 'utf8');
+              await github.graphql(`
+                mutation($discussionId: ID!, $body: String!) {
+                  addDiscussionComment(input: {
+                    discussionId: $discussionId,
+                    body: $body
+                  }) {
+                    comment { id }
+                  }
+                }
+              `, { discussionId, body: commentBody });
+              console.log(`Posted detail comment ${i + 1}/${commentCount}`);
+            }
 
       - name: Fallback — Create Issue
         if: steps.create-discussion.outcome == 'failure'
@@ -358,7 +378,17 @@ jobs:
         run: |
           # Create label if it doesn't exist (ignore errors if it already exists)
           gh label create "skill-quality" --description "Automated skill quality reports" --color "d4c5f9" 2>/dev/null || true
-          gh issue create \
+          ISSUE_URL=$(gh issue create \
             --title "${{ steps.report.outputs.title }}" \
             --body-file report-body.md \
-            --label "skill-quality"
+            --label "skill-quality")
+          echo "Created issue: $ISSUE_URL"
+
+          # Post overflow detail comments on the issue
+          COMMENT_COUNT=${{ steps.report.outputs.comment_count }}
+          for i in $(seq 0 $(( ${COMMENT_COUNT:-0} - 1 ))); do
+            if [ -f "report-comment-${i}.md" ]; then
+              gh issue comment "$ISSUE_URL" --body-file "report-comment-${i}.md"
+              echo "Posted detail comment $((i+1))/${COMMENT_COUNT}"
+            fi
+          done