feat: separate core vs niche skills and enforce research-first default

* Initial plan

* docs: document core skill scope

---------

Co-authored-by: openai-code-agent[bot] <242516109+Codex@users.noreply.github.com>

skills/configure-ecc/SKILL.md

@@ -64,7 +64,23 @@ mkdir -p $TARGET/skills $TARGET/rules
 
 ## Step 2: Select & Install Skills
 
-### 2a: Choose Skill Categories
+### 2a: Choose Scope (Core vs Niche)
+
+Default to **Core (recommended for new users)** — copy `.agents/skills/*` plus `skills/search-first/` for research-first workflows. This bundle covers engineering, evals, verification, security, strategic compaction, frontend design, and Anthropic cross-functional skills (article-writing, content-engine, market-research, frontend-slides).
+
+Use `AskUserQuestion` (single select):
+```
+Question: "Install core skills only, or include niche/framework packs?"
+Options:
+  - "Core only (recommended)" — "tdd, e2e, evals, verification, research-first, security, frontend patterns, compacting, cross-functional Anthropic skills"
+  - "Core + selected niche" — "Add framework/domain-specific skills after core"
+  - "Niche only" — "Skip core, install specific framework/domain skills"
+Default: Core only
+```
+
+If the user chooses niche or core + niche, continue to category selection below and only include those niche skills they pick.
+
+### 2b: Choose Skill Categories
 
 There are 27 skills organized into 4 categories. Use `AskUserQuestion` with `multiSelect: true`:
 
@@ -77,7 +93,7 @@ Options:
   - "All skills" — "Install every available skill"
 ```
 
-### 2b: Confirm Individual Skills
+### 2c: Confirm Individual Skills
 
 For each selected category, print the full list of skills below and ask the user to confirm or deselect specific ones. If the list exceeds 4 items, print the list as text and use `AskUserQuestion` with an "Install all listed" option plus "Other" for the user to paste specific names.
 
@@ -140,7 +156,7 @@ For each selected category, print the full list of skills below and ask the user
 |-------|-------------|
 | `project-guidelines-example` | Template for creating project-specific skills |
 
-### 2c: Execute Installation
+### 2d: Execute Installation
 
 For each selected skill, copy the entire skill directory:
 ```bash

skills/search-first/SKILL.md

@@ -61,10 +61,11 @@ Use this skill when:
 
 Before writing a utility or adding functionality, mentally run through:
 
+0. Does this already exist in the repo? → `rg` through relevant modules/tests first
 1. Is this a common problem? → Search npm/PyPI
 2. Is there an MCP for this? → Check `~/.claude/settings.json` and search
 3. Is there a skill for this? → Check `~/.claude/skills/`
-4. Is there a GitHub template? → Search GitHub
+4. Is there a GitHub implementation/template? → Run GitHub code search for maintained OSS before writing net-new code
 
 ### Full Mode (agent)