fix: make all 165 skills load in Claude Code and Codex

Both plugin manifests pointed `skills` at the bare "./skills/" root, but
Claude Code and Codex scan only one directory level deep while skills are
nested two levels deep (skills/<domain>/<skill>/SKILL.md), so both surfaces
discovered zero skills. List the 20 domain folders explicitly in BOTH
.claude-plugin/plugin.json and .codex-plugin/plugin.json.

Resolve the duplicate `critical-thinking-task-designer` slug (present in
curriculum-assessment and literacy-critical-thinking) that collides in any
flat name-keyed loader: rename the curriculum-assessment copy to
discipline-specific-critical-thinking-task-designer (folder + frontmatter
name/skill_id/skill_name). The MCP server, which already namespaced the
duplicate as domain__slug, now exposes both under clean un-prefixed names.

Regenerated registry.json and mcp-server/src/skills.json via the repo's own
scripts (165 = 165 = 165). Updated tests to the new manifest-array and
resolved-collision contracts, and added a CONTRIBUTING.md governance note
(name uniqueness across domains; new domains must be added to both manifests).

Verified: validate-skills 0 errors, validate-registry 165/20, claude plugin
validate passes, `claude plugin details` reports Skills (165), both Playwright
suites green (root 21, mcp-server 20).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: GarethManning

.claude-plugin/plugin.json

@@ -9,5 +9,26 @@
   },
   "homepage": "https://github.com/GarethManning/education-agent-skills",
   "license": "CC BY-SA 4.0",
-  "skills": "./skills/"
+  "skills": [
+    "./skills/ai-learning-science",
+    "./skills/ai-literacy",
+    "./skills/curriculum-alignment",
+    "./skills/curriculum-assessment",
+    "./skills/eal-language-development",
+    "./skills/environmental-experiential-learning",
+    "./skills/explicit-instruction",
+    "./skills/global-cross-cultural-pedagogies",
+    "./skills/historical-thinking",
+    "./skills/inclusive-design",
+    "./skills/literacy-critical-thinking",
+    "./skills/memory-learning-science",
+    "./skills/montessori-alternative-approaches",
+    "./skills/original-frameworks",
+    "./skills/professional-learning",
+    "./skills/questioning-discussion",
+    "./skills/self-regulated-learning",
+    "./skills/student-learning",
+    "./skills/systems-thinking",
+    "./skills/wellbeing-motivation-agency"
+  ]
 }

.codex-plugin/plugin.json

@@ -4,7 +4,28 @@
   "description": "165 evidence-based education skills for curriculum design, lesson planning, assessment, and AI-assisted teaching — built on the Agent Skills open standard.",
   "repository": "https://github.com/GarethManning/education-agent-skills",
   "license": "CC-BY-SA-4.0",
-  "skills": "./skills/",
+  "skills": [
+    "./skills/ai-learning-science",
+    "./skills/ai-literacy",
+    "./skills/curriculum-alignment",
+    "./skills/curriculum-assessment",
+    "./skills/eal-language-development",
+    "./skills/environmental-experiential-learning",
+    "./skills/explicit-instruction",
+    "./skills/global-cross-cultural-pedagogies",
+    "./skills/historical-thinking",
+    "./skills/inclusive-design",
+    "./skills/literacy-critical-thinking",
+    "./skills/memory-learning-science",
+    "./skills/montessori-alternative-approaches",
+    "./skills/original-frameworks",
+    "./skills/professional-learning",
+    "./skills/questioning-discussion",
+    "./skills/self-regulated-learning",
+    "./skills/student-learning",
+    "./skills/systems-thinking",
+    "./skills/wellbeing-motivation-agency"
+  ],
   "interface": {
     "displayName": "Education Agent Skills",
     "shortDescription": "165 evidence-based skills for curriculum design, lesson planning, and assessment",

CONTRIBUTING.md

@@ -51,6 +51,23 @@ Every `SKILL.md` must preserve:
 - input and output schemas;
 - any existing citations and limitations.
 
+### Skill `name` must be unique across all domains
+
+A skill's `name` (and its `skill_id` slug) must be **unique across the whole library, not just within its own domain folder**. Claude Code and Codex identify a skill by its `name`; a flat, name-keyed loader cannot hold two skills with the same `name`, so one silently collides with or overwrites the other. (The MCP server tolerates duplicates by qualifying them with the domain, but the plugin surfaces do not.)
+
+If two skills would share a slug, give one a more specific name — for example `discipline-specific-critical-thinking-task-designer` rather than a second `critical-thinking-task-designer` — and update that `SKILL.md`'s frontmatter `name`, `skill_id`, and `skill_name` plus its folder name to match.
+
+### New domain folders must be added to BOTH plugin manifests
+
+The `skills` field in each plugin manifest is an **explicit array of the domain folder paths** (e.g. `"./skills/curriculum-assessment"`), because Claude Code and Codex scan only one directory level deep while this repo nests skills two levels deep (`skills/<domain>/<skill>/SKILL.md`). A bare `"./skills/"` root path makes both loaders discover zero skills.
+
+When you add a **new domain folder**, add its path to the `skills` array in **both**:
+
+- `.claude-plugin/plugin.json`
+- `.codex-plugin/plugin.json`
+
+(`.claude-plugin/marketplace.json` inherits via its `source` field and does not list skills.)
+
 ## Validation before a pull request
 
 After adding or editing skills, run:

mcp-server/src/skills.json

@@ -153,17 +153,22 @@ test.describe("MCP Server — skill tools", () => {
     expect(text).toContain("Year 9 novice");
   });
 
-  test("handles collision names with domain prefix", async () => {
+  // The former slug collision (two `critical-thinking-task-designer` skills) was
+  // resolved by renaming the curriculum-assessment copy. With no duplicate slug,
+  // buildToolName exposes clean, un-prefixed tool names on both surfaces.
+  test("exposes both critical-thinking skills under distinct un-prefixed names", async () => {
     const { tools } = await client.listTools();
     const criticalThinkingTools = tools.filter((t) =>
       t.name.includes("critical-thinking-task-designer"),
     );
 
     expect(criticalThinkingTools.length).toBe(2);
     expect(criticalThinkingTools.map((t) => t.name).sort()).toEqual([
-      "curriculum-assessment__critical-thinking-task-designer",
-      "literacy-critical-thinking__critical-thinking-task-designer",
+      "critical-thinking-task-designer",
+      "discipline-specific-critical-thinking-task-designer",
     ]);
+    // No domain-prefixed (collision) form should remain.
+    expect(tools.some((t) => t.name.includes("__"))).toBe(false);
   });
 });
 
@@ -201,17 +206,21 @@ test.describe("MCP Server — skill prompts", () => {
     expect(text.text).toContain("Year 9 novice");
   });
 
-  test("handles collision names with domain prefix", async () => {
+  // Mirror of the tools-side check: the resolved collision means both
+  // critical-thinking prompts are registered under clean, un-prefixed names.
+  test("exposes both critical-thinking prompts under distinct un-prefixed names", async () => {
     const { prompts } = await client.listPrompts();
     const criticalThinking = prompts.filter((p) =>
       p.name.includes("critical-thinking-task-designer"),
     );
 
     expect(criticalThinking.length).toBe(2);
     expect(criticalThinking.map((p) => p.name).sort()).toEqual([
-      "curriculum-assessment__critical-thinking-task-designer",
-      "literacy-critical-thinking__critical-thinking-task-designer",
+      "critical-thinking-task-designer",
+      "discipline-specific-critical-thinking-task-designer",
     ]);
+    // No domain-prefixed (collision) form should remain.
+    expect(prompts.some((p) => p.name.includes("__"))).toBe(false);
   });
 });
 

mcp-server/tests/mcp-server.spec.ts

@@ -1,6 +1,6 @@
 {
   "version": "2.0",
-  "generated": "2026-05-27T14:54:56.907578+00:00",
+  "generated": "2026-06-26T11:24:25.994801+00:00",
   "standard": "agent-skills-1.0",
   "total_skills": 165,
   "domains": [
@@ -1051,41 +1051,6 @@
       },
       "path": "skills/curriculum-assessment/criterion-referenced-rubric-generator/SKILL.md"
     },
-    {
-      "id": "curriculum-assessment/critical-thinking-task-designer",
-      "name": "critical-thinking-task-designer",
-      "display_name": "Critical Thinking Task Designer",
-      "domain": "curriculum-assessment",
-      "description": "Design discipline-specific critical thinking tasks grounded in knowledge-contingent reasoning rather than generic skills. Use when embedding higher-order thinking into subject content.",
-      "disable_model_invocation": false,
-      "evidence_strength": "strong",
-      "tags": [
-        "critical-thinking",
-        "disciplinary-thinking",
-        "horizontal-knowledge",
-        "knowledge-contingent",
-        "task-design",
-        "intellectual-resources",
-        "Bailin",
-        "Willingham",
-        "domain-specific"
-      ],
-      "teacher_time": "10 minutes",
-      "chains_with": [
-        "curriculum-knowledge-architecture-designer",
-        "kud-knowledge-type-mapper",
-        "coherent-rubric-logic-builder",
-        "learning-target-authoring-guide",
-        "ai-output-critical-audit-designer"
-      ],
-      "chain_edges": {
-        "receives_from": [],
-        "feeds_into": [],
-        "output_field": null,
-        "input_field": null
-      },
-      "path": "skills/curriculum-assessment/critical-thinking-task-designer/SKILL.md"
-    },
     {
       "id": "curriculum-assessment/curriculum-knowledge-architecture-designer",
       "name": "curriculum-knowledge-architecture-designer",
@@ -1150,6 +1115,41 @@
       },
       "path": "skills/curriculum-assessment/differentiation-adapter/SKILL.md"
     },
+    {
+      "id": "curriculum-assessment/discipline-specific-critical-thinking-task-designer",
+      "name": "discipline-specific-critical-thinking-task-designer",
+      "display_name": "Discipline-Specific Critical Thinking Task Designer",
+      "domain": "curriculum-assessment",
+      "description": "Design discipline-specific critical thinking tasks grounded in knowledge-contingent reasoning rather than generic skills. Use when embedding higher-order thinking into subject content.",
+      "disable_model_invocation": false,
+      "evidence_strength": "strong",
+      "tags": [
+        "critical-thinking",
+        "disciplinary-thinking",
+        "horizontal-knowledge",
+        "knowledge-contingent",
+        "task-design",
+        "intellectual-resources",
+        "Bailin",
+        "Willingham",
+        "domain-specific"
+      ],
+      "teacher_time": "10 minutes",
+      "chains_with": [
+        "curriculum-knowledge-architecture-designer",
+        "kud-knowledge-type-mapper",
+        "coherent-rubric-logic-builder",
+        "learning-target-authoring-guide",
+        "ai-output-critical-audit-designer"
+      ],
+      "chain_edges": {
+        "receives_from": [],
+        "feeds_into": [],
+        "output_field": null,
+        "input_field": null
+      },
+      "path": "skills/curriculum-assessment/discipline-specific-critical-thinking-task-designer/SKILL.md"
+    },
     {
       "id": "curriculum-assessment/formative-assessment-technique-selector",
       "name": "formative-assessment-technique-selector",

registry.json

@@ -1,15 +1,15 @@
 ---
 # AGENT SKILLS STANDARD FIELDS (v2)
-name: critical-thinking-task-designer
+name: discipline-specific-critical-thinking-task-designer
 description: "Design discipline-specific critical thinking tasks grounded in knowledge-contingent reasoning rather than generic skills. Use when embedding higher-order thinking into subject content."
 disable-model-invocation: false
 user-invocable: true
 effort: medium
 
 # EXISTING FIELDS
 
-skill_id: "curriculum-assessment/critical-thinking-task-designer"
-skill_name: "Critical Thinking Task Designer"
+skill_id: "curriculum-assessment/discipline-specific-critical-thinking-task-designer"
+skill_name: "Discipline-Specific Critical Thinking Task Designer"
 domain: "curriculum-assessment"
 version: "1.0"
 evidence_strength: "strong"

…critical-thinking-task-designer/SKILL.md …critical-thinking-task-designer/SKILL.mdskills/curriculum-assessment/critical-thinking-task-designer/SKILL.md renamed to skills/curriculum-assessment/discipline-specific-critical-thinking-task-designer/SKILL.md skills/curriculum-assessment/critical-thinking-task-designer/SKILL.md renamed to skills/curriculum-assessment/discipline-specific-critical-thinking-task-designer/SKILL.md

@@ -6,6 +6,7 @@ import * as yaml from "yaml";
 const SKILLS_DIR = path.join(__dirname, "..", "skills");
 const REGISTRY_PATH = path.join(__dirname, "..", "registry.json");
 const PLUGIN_PATH = path.join(__dirname, "..", ".claude-plugin", "plugin.json");
+const CODEX_PLUGIN_PATH = path.join(__dirname, "..", ".codex-plugin", "plugin.json");
 
 // Helper: collect all SKILL.md paths
 function getAllSkillPaths(): string[] {
@@ -188,7 +189,7 @@ test.describe("Plugin Manifest Validation", () => {
     name: string;
     display_name: string;
     version: string;
-    skills: string;
+    skills: string[];
     license: string;
   };
 
@@ -202,10 +203,33 @@ test.describe("Plugin Manifest Validation", () => {
     expect(plugin.version).toBe("2.1.0");
   });
 
-  test("plugin.json skills directory exists", () => {
-    const skillsDir = path.join(__dirname, "..", plugin.skills);
-    expect(fs.existsSync(skillsDir)).toBe(true);
-    expect(fs.statSync(skillsDir).isDirectory()).toBe(true);
+  // Claude Code and Codex scan only one directory level deep, while skills are
+  // nested two levels deep (skills/<domain>/<skill>/SKILL.md). The `skills`
+  // field must therefore be an explicit array of every domain folder, not the
+  // bare "./skills/" root (which would discover zero skills).
+  test("plugin.json skills field lists every domain folder", () => {
+    const domainsOnDisk = fs
+      .readdirSync(SKILLS_DIR)
+      .filter((d) => fs.statSync(path.join(SKILLS_DIR, d)).isDirectory())
+      .map((d) => `./skills/${d}`)
+      .sort();
+
+    expect(Array.isArray(plugin.skills)).toBe(true);
+    expect([...plugin.skills].sort()).toEqual(domainsOnDisk);
+
+    for (const entry of plugin.skills) {
+      const skillsDir = path.join(__dirname, "..", entry);
+      expect(fs.existsSync(skillsDir)).toBe(true);
+      expect(fs.statSync(skillsDir).isDirectory()).toBe(true);
+    }
+  });
+
+  // The Codex manifest must stay in lockstep with the Claude manifest so the
+  // same domain folders load on both surfaces (see CONTRIBUTING.md governance).
+  test("codex plugin.json skills field matches the claude manifest", () => {
+    const codex = JSON.parse(fs.readFileSync(CODEX_PLUGIN_PATH, "utf-8"));
+    expect(Array.isArray(codex.skills)).toBe(true);
+    expect([...codex.skills].sort()).toEqual([...plugin.skills].sort());
   });
 
   test("plugin.json has correct license", () => {