Pattern miner: Add nitpick-reviewer curated archetype for slash-command PR review

.github/copilot-instructions.md

@@ -4,7 +4,7 @@ You are an expert GitHub Agentic Workflow generator. You help users create produ
 
 ## Your Knowledge
 
-Use the committed pattern library as the source of truth: `patterns/manifest.json` plus `patterns/archetypes/*.json` generated on 2026-08-31 from 223 source repos, 175 active workflows, and 671 total workflows scanned. The current wizard manifest lists 27 user-facing archetypes; the `custom` archetype exists as a supporting pattern file and is intentionally not exposed as a HOW-step archetype.
+Use the committed pattern library as the source of truth: `patterns/manifest.json` plus `patterns/archetypes/*.json` generated on 2026-08-31 from 223 source repos, 175 active workflows, and 671 total workflows scanned. The current wizard manifest lists 28 user-facing archetypes; the `custom` archetype exists as a supporting pattern file and is intentionally not exposed as a HOW-step archetype.
 
 ### Key Data Points
 
@@ -23,7 +23,7 @@ Use the committed pattern library as the source of truth: `patterns/manifest.jso
 - `custom` is hidden from the wizard archetype cards but retained for matching and profile data. Best observed custom profiles are schedule + create-pull-request + noop at 95.2% (n=21), schedule + create-issue + noop + threat-detection at 83.9%, and schedule + create-issue + noop at 80.0%.
 
 **Curated archetypes without empirical runs yet (`count: 0`):**
-- accessibility-expert, agent-cost-tracker, ci-failure-triage, code-health-auditor, community-digest, contribution-guidelines-checker, issue-hierarchy-manager, link-checker, linter-applier, linter-miner, linter-refiner, linter-workflows, performance-nut, pr-iteration-loop, repo-qa-assistant, security-scanner, skill-pr-reviewer, user-simulator.
+- accessibility-expert, agent-cost-tracker, ci-failure-triage, code-health-auditor, community-digest, contribution-guidelines-checker, issue-hierarchy-manager, link-checker, linter-applier, linter-miner, linter-refiner, linter-workflows, nitpick-reviewer, performance-nut, pr-iteration-loop, repo-qa-assistant, security-scanner, skill-pr-reviewer, user-simulator.
 - Keep these archetypes available. They are newer curated patterns and should not be removed simply because they have no measured success rate.
 
 **Trigger combo risk:**

patterns/archetypes/nitpick-reviewer.json

@@ -0,0 +1,35 @@
+{
+  "id": "nitpick-reviewer",
+  "label": "Nitpick Reviewer",
+  "description": "Review a pull request on demand via slash command and leave line-level nitpicks with a final review verdict",
+  "success_rate": null,
+  "count": 0,
+  "recommended_triggers": [
+    {
+      "type": "slash_command",
+      "config": {}
+    }
+  ],
+  "recommended_safe_outputs": [
+    "create-pull-request-review-comment"
+  ],
+  "recommended_tools": [
+    "create-pull-request-review-comment"
+  ],
+  "timeout_minutes": 15,
+  "prompt_style": "role-rules",
+  "size_range_bytes": [
+    2000,
+    6000
+  ],
+  "top_repos": [],
+  "tips": [
+    "Trigger with slash_command on pull_request_comment and pull_request_review_comment events so reviewers invoke it on demand rather than on every push",
+    "Pair create-pull-request-review-comment with submit-pull-request-review to post line comments plus one final review verdict",
+    "Set submit-pull-request-review allowed-events to [COMMENT, REQUEST_CHANGES] — the default GITHUB_TOKEN cannot APPROVE a pull request",
+    "Use cache-memory to record prior findings per PR so repeated invocations do not repost the same nitpicks",
+    "Set tools.github.min-integrity to approved or none depending on whether only trusted authors or any maintainer-invoked command can trigger it",
+    "Cap max on both create-pull-request-review-comment and submit-pull-request-review to keep reviews focused"
+  ],
+  "anti_patterns": []
+}

patterns/manifest.json

@@ -32,7 +32,8 @@
     "agent-cost-tracker",
     "contribution-guidelines-checker",
     "link-checker",
-    "repo-qa-assistant"
+    "repo-qa-assistant",
+    "nitpick-reviewer"
   ],
   "workflow_generation": "workflow-generation.json",
   "anti_patterns": [

patterns/workflow-generation.json

@@ -834,6 +834,48 @@
       ],
       "min_integrity": "approved"
     },
+    "nitpick-reviewer": {
+      "icon": "eye",
+      "capabilities": {
+        "github_toolsets": true
+      },
+      "permissions": [
+        "contents",
+        "pull-requests"
+      ],
+      "github_toolsets": [
+        "repos",
+        "pull_requests"
+      ],
+      "instructions": [
+        "pr-reviewer.md"
+      ],
+      "trigger_overrides": {
+        "slash_command": {
+          "yaml": "slash_command:\n  name: {{name}}\n  events: [pull_request_comment, pull_request_review_comment]",
+          "description": "on a slash command left as a pull request comment"
+        }
+      },
+      "body": [
+        "# {{label}}",
+        "",
+        "You are an **on-demand pull request nitpick reviewer** for this repository, invoked by a slash command.",
+        "",
+        "## Process",
+        "",
+        "1. Read the pull request diff, the invoking comment, and any prior review notes in cache-memory",
+        "2. Review changed lines for style, best-practice, and minor-improvement opportunities",
+        "3. Leave specific, line-level review comments and one overall review verdict",
+        "4. Record findings in cache-memory so a repeat invocation does not repost the same nitpicks",
+        "",
+        "## Constraints",
+        "",
+        "- **DO NOT** approve the pull request — submit only COMMENT or REQUEST_CHANGES reviews.",
+        "- **DO NOT** duplicate a nitpick already recorded in cache-memory for this pull request.",
+        "- **DO NOT** review generated, vendored, or lock files."
+      ],
+      "min_integrity": "approved"
+    },
     "security-scanner": {
       "icon": "shield",
       "capabilities": {

test/copilot-instructions.test.js

@@ -28,7 +28,7 @@ describe('copilot instructions pattern guidance', () => {
     }
 
     expect(empirical).toHaveLength(9);
-    expect(curated).toHaveLength(18);
+    expect(curated).toHaveLength(19);
     for (const id of empirical) expect(instructions).toContain(`\`${id}\``);
     for (const id of curated) expect(instructions).toContain(id);
     expect(instructions).toContain('`custom` is hidden from the wizard archetype cards');

test/patterns.test.js

@@ -106,7 +106,8 @@ describe('getArchetype', () => {
       'skill-pr-reviewer',
       'security-scanner',
       'ci-failure-triage',
-      'agent-cost-tracker'
+      'agent-cost-tracker',
+      'nitpick-reviewer'
     ])('includes %s with triggers and safe outputs', (id) => {
       const archetype = getArchetype(generatedPatterns, id);
       expect(archetype).not.toBeNull();