co-mono/packages/coding-agent/docs/extension-loading.md

Extension Loading

Unified system for loading hooks, tools, skills, and themes from local files, directories, npm packages, and git repositories.

Extension Types

Type	Root Entry	Subdir Entry	Purpose
Hooks	*.ts / *.js	index.ts / index.js / package.json main	Event handlers for agent lifecycle
Tools	*.ts / *.js	index.ts / index.js / package.json main	Custom tools for the agent
Skills	*.md	SKILL.md	Context/instructions loaded into agent
Themes	*.theme.json	*.theme.json (recursive)	Color schemes for TUI

Note: Themes use *.theme.json pattern scanned recursively at all levels, allowing flat theme packs without requiring subdirectories.

Sources

Extensions can be loaded from:

File Paths

./my-hook.ts
~/global-hook.ts
/absolute/path/hook.ts

Directories

./my-hooks/
~/.pi/agent/hooks/

npm Packages

npm:package-name
npm:package-name@1.2.3
npm:package-name@latest
npm:@scope/package-name
npm:@scope/package-name@1.2.3

Git Repositories

git:https://github.com/user/repo
git:https://github.com/user/repo@v1.0.0      # tag
git:https://github.com/user/repo@abc123f     # commit
git:https://github.com/user/repo#branch      # branch

Storage Layout

Permanent (settings.json)

~/.pi/agent/
  hooks/
    my-local-hook.ts                    # root-level file
    complex-hook/                       # directory with entry point
      index.ts
      utils.ts
    npm/
      my-hook@1.2.3/                    # npm package
        package.json
        node_modules/
        index.js
      @scope/
        scoped-hook@2.0.0/
          ...
    git/
      github.com/user/repo@v1.0.0/      # git repo
        ...
  tools/
    ... (same structure)
  skills/
    ... (same structure, but SKILL.md instead of index.ts)
  themes/
    dark.theme.json                     # root-level theme
    light.theme.json
    community-pack/                     # theme pack (no entry point needed)
      nord.theme.json
      dracula.theme.json
    npm/
      cool-themes@1.0.0/
        monokai.theme.json
        solarized.theme.json

Ephemeral (CLI flags)

/tmp/pi-extensions/
  hooks/
    npm/
      my-hook@1.0.0/
    git/
      github.com/user/repo@v1.0.0/
  tools/
    ...
  skills/
    ...
  themes/
    ...

Temp directory persists until OS clears /tmp/. No re-download needed across sessions (usually).

Entry Point Resolution

For each discovered directory, resolve entry point in order:

Hooks & Tools

1. index.ts (if exists)
2. index.js (if exists)
3. main field in package.json (if exists)

Skills

1. SKILL.md (required)

Themes

Themes use recursive pattern matching instead of fixed entry points:

• Scan recursively for *.theme.json files at all levels
• Each matching file is a separate theme
• Path derived from filename (e.g., dark.theme.json → dark, pack/nord.theme.json → pack/nord)

Scanning Algorithm

scan(baseDir, config):
  results = []
  
  for entry in baseDir:
    skip if entry.name starts with "."
    skip if entry.name == "node_modules"
    skip if entry.name ends with ".installing"
    
    if entry is file:
      if matches rootPattern (e.g., *.ts, *.js, *.md, *.theme.json):
        results.add(entry)
    
    if entry is directory:
      if config.recursivePattern:
        # For themes: scan recursively for *.theme.json everywhere
        results.addAll(scan(directory, config))
      else if has entryPoint (index.ts, index.js, SKILL.md):
        results.add(directory)  # load as single extension
      else:
        results.addAll(scan(directory, config))  # recurse to find extensions
  
  return results

Default directories scanned (always, regardless of settings.json):

• ~/.pi/agent/<type>/
• <cwd>/.pi/<type>/

Extension Packs

A key use case is pulling in a pack (collection) of extensions via a directory, npm package, or git repo, then filtering to a subset.

Example: Skill pack

npm:pi-skills@1.0.0 contains:
  skills/
    brave-search/SKILL.md
    browser-tools/SKILL.md
    transcribe/SKILL.md
    youtube-transcript/SKILL.md
    ... (10+ skills)

You want only 2 of them:

{
  "skills": {
    "paths": ["npm:pi-skills@1.0.0"],
    "filter": ["brave-search", "youtube-transcript"]
  }
}

Example: Theme pack

npm:community-themes@1.0.0 contains:
  themes/
    nord.theme.json
    dracula.theme.json
    solarized-dark.theme.json
    solarized-light.theme.json
    monokai.theme.json

Exclude solarized variants:

{
  "themes": {
    "paths": ["npm:community-themes@1.0.0"],
    "filter": ["!solarized-*"]
  }
}

Example: Hook pack

npm:audit-hooks@1.0.0 contains:
  hooks/
    file-audit/index.ts
    command-audit/index.ts
    network-audit/index.ts
    debug-logger/index.ts

All except debug:

{
  "hooks": {
    "paths": ["npm:audit-hooks@1.0.0"],
    "filter": ["!debug-*"]
  }
}

Filtering

Single filter array with ! prefix for exclusion. Patterns are matched against extension paths (directory or filename without extension).

{
  "filter": ["pattern1", "pattern2", "!excluded-pattern"]
}

Logic:

1. Collect all patterns without ! prefix → include patterns
2. Collect all patterns with ! prefix → exclude patterns
3. If include patterns exist: start with extensions matching any include pattern
4. If no include patterns: start with all extensions
5. Remove extensions matching any exclude pattern

Examples:

["brave-search"]                    // only brave-search
["brave-*", "docker"]               // brave-search, brave-api, docker
["!transcribe"]                     // all except transcribe
["audit-*", "!audit-debug"]         // audit-* except audit-debug

Patterns are glob patterns matched against extension paths.

CLI Arguments

Adding Sources

pi --hook <path|npm:|git:>      # add hook source (repeatable)
pi --tool <path|npm:|git:>      # add custom tool source (repeatable)
pi --skill <path|npm:|git:>     # add skill source (repeatable)
pi --theme <path|npm:|git:>     # add theme source (repeatable)

Installation locations for npm/git sources:

Source	Install location
CLI flags	/tmp/pi-extensions/<type>/npm/ or git/
Global settings (~/.pi/agent/settings.json)	~/.pi/agent/<type>/npm/ or git/
Project settings (<cwd>/.pi/settings.json)	<cwd>/.pi/<type>/npm/ or git/

File/directory paths are used directly (no installation).

• CLI = ephemeral: cached in temp until OS clears /tmp/
• Global settings = permanent: installed to user's agent directory
• Project settings = project-local: installed to project's .pi/ directory

Examples:

• --hook npm:my-hook@1.0.0 → /tmp/pi-extensions/hooks/npm/my-hook@1.0.0/
• Global settings.json npm:my-hook@1.0.0 → ~/.pi/agent/hooks/npm/my-hook@1.0.0/
• Project settings.json npm:my-hook@1.0.0 → <cwd>/.pi/hooks/npm/my-hook@1.0.0/

This encourages: try via CLI, if you like it, add to settings.json for permanent install.

Filtering

pi --hooks "pattern1,pattern2,!excluded"       # filter hooks
pi --custom-tools "pattern1,!excluded"         # filter custom tools
pi --skills "pattern1,pattern2"                # filter skills
pi --themes "pattern1"                         # filter themes

Disabling

pi --no-hooks                   # disable all hooks
pi --no-custom-tools            # disable all custom tools
pi --no-skills                  # disable all skills (already exists)

Built-in Tools

pi --tools read,bash,edit,write    # select which built-in tools to enable (unchanged)

Settings Hierarchy

Extensions are configured in settings.json at two levels:

• Global: ~/.pi/agent/settings.json
• Project: <cwd>/.pi/settings.json

Merge behavior:

• paths: additive - project paths are added to global paths
• filter: override - project filter replaces global filter if specified

Example:

// Global: ~/.pi/agent/settings.json
{
  "hooks": {
    "paths": ["npm:audit-hooks@1.0.0"],
    "filter": ["!debug-*"]
  }
}

// Project: .pi/settings.json
{
  "hooks": {
    "paths": ["./project-hooks/"],
    "filter": ["audit-*"]           // overrides global filter
  }
}

// Effective:
{
  "hooks": {
    "paths": ["npm:audit-hooks@1.0.0", "./project-hooks/"],
    "filter": ["audit-*"]
  }
}

settings.json Structure

{
  "hooks": {
    "paths": [
      "./my-hooks/",
      "npm:@scope/hook@1.0.0",
      "git:https://github.com/user/hooks@v1.0.0"
    ],
    "filter": ["audit-*", "!audit-debug"]
  },
  "tools": {
    "paths": ["npm:cool-tools@2.0.0"],
    "filter": ["!dangerous-tool"]
  },
  "skills": {
    "paths": ["npm:pi-skills@1.0.0", "~/my-skills/"],
    "filter": ["brave-search", "git-*", "!git-legacy"]
  },
  "themes": {
    "paths": ["npm:community-themes@1.0.0"]
  }
}

Migration from current format:

• hooks: string[] → hooks.paths: string[]
• customTools: string[] → tools.paths: string[]
• skills.customDirectories → skills.paths
• skills.includeSkills → skills.filter (patterns without !)
• skills.ignoredSkills → skills.filter (patterns with ! prefix)

Installation Flow

Target directory depends on source:

• CLI flags: /tmp/pi-extensions/<type>/npm/ or git/
• Global settings.json: ~/.pi/agent/<type>/npm/ or git/
• Project settings.json: <cwd>/.pi/<type>/npm/ or git/

Atomic Installation

To prevent corrupted state from interrupted installs (Ctrl+C):

1. Install to <target>.installing/ (temporary)
2. On success, atomically rename to <target>/
3. If interrupted, <target>/ doesn't exist → next run retries cleanly
4. Scanner filters out *.installing directories (see Scanning Algorithm)

npm Packages

1. Parse specifier: npm:@scope/pkg@1.2.3 → name: @scope/pkg, version: 1.2.3
2. Determine target dir based on source (CLI → temp, global → agent dir, project → cwd/.pi/)
3. If <target>/ exists and has matching version in package.json → skip install
4. Otherwise:
   • Remove stale <target>.installing/ if exists
   • npm pack @scope/pkg@1.2.3 → download tarball
   • Extract to <target>.installing/
   • If package.json has dependencies → run npm install
   • Rename <target>.installing/ → <target>/

Git Repositories

1. Parse specifier: git:https://github.com/user/repo@v1.0.0
2. Determine target dir based on source (CLI → temp, global → agent dir, project → cwd/.pi/)
3. If <target>/ exists → skip clone
4. Otherwise:
   • Remove stale <target>.installing/ if exists
   • git clone <url> to <target>.installing/
   • git checkout <tag|commit|branch>
   • If package.json has dependencies → run npm install
   • Rename <target>.installing/ → <target>/

Update Command

pi update                  # update all extensions
pi update hooks            # update only hooks
pi update tools skills     # update specific types

Behavior:

• For npm:pkg@<version>: check if newer version of that exact spec exists (e.g., @latest resolves to newer)
• For git:repo#branch: git pull
• For git:repo@tag or git:repo@commit: no-op (pinned)
• Local files/directories: no-op

Loading Flow (Full)

1. Collect sources:

   • Default directories: ~/.pi/agent/<type>/, ./.pi/<type>/
   • settings.json <type>.paths
   • CLI --<type> arguments

2. Install remote sources:

   • Process npm: and git: specifiers
   • Install to ~/.pi/agent/<type>/npm/ or git/

3. Scan all sources:

   • Recursively discover extensions
   • Compute relative path for each

4. Apply filter:

   • Combine settings.json <type>.filter and CLI --<type>s patterns
   • Filter by path (no loading yet)

5. Load survivors:

   • Parse/execute only extensions that passed filter
   • Validate (frontmatter, exports, schema)
   • Report errors for invalid extensions

---

Implementation Plan

Overview

This implementation consolidates four separate loading systems (hooks, tools, skills, themes) into a unified extension loading framework with shared logic for source resolution, installation, scanning, filtering, and loading.

New Files

src/core/extensions/types.ts

Extension type definitions shared across all loaders.

export type ExtensionType = "hooks" | "tools" | "skills" | "themes";

export interface ExtensionSource {
  type: "file" | "directory" | "npm" | "git";
  specifier: string;        // original specifier from config/CLI
  resolvedPath?: string;    // resolved local path after install
}

export interface DiscoveredExtension {
  path: string;             // relative path (e.g., "brave-search", "npm/@scope/pkg@1.0.0")
  absolutePath: string;     // absolute filesystem path
  entryPoint: string;       // resolved entry point file
  source: ExtensionSource;
}

export interface ExtensionConfig {
  paths?: string[];
  filter?: string[];
}

export interface ExtensionTypeConfig {
  rootPatterns: string[];           // e.g., ["*.ts", "*.js"]
  subdirEntryPoints: string[];      // e.g., ["index.ts", "index.js"]
  packageJsonFallback: boolean;     // whether to check package.json main
}

export const EXTENSION_CONFIGS: Record<ExtensionType, ExtensionTypeConfig> = {
  hooks: {
    rootPatterns: ["*.ts", "*.js"],
    subdirEntryPoints: ["index.ts", "index.js"],
    packageJsonFallback: true,
    recursivePattern: false,
  },
  tools: {
    rootPatterns: ["*.ts", "*.js"],
    subdirEntryPoints: ["index.ts", "index.js"],
    packageJsonFallback: true,
    recursivePattern: false,
  },
  skills: {
    rootPatterns: ["*.md"],
    subdirEntryPoints: ["SKILL.md"],
    packageJsonFallback: false,
    recursivePattern: false,
  },
  themes: {
    rootPatterns: ["*.theme.json"],
    subdirEntryPoints: [],              // not used
    packageJsonFallback: false,
    recursivePattern: true,             // scan for *.theme.json at all levels
  },
};

src/core/extensions/source-resolver.ts

Handles parsing and installing npm/git sources.

export function parseSource(specifier: string): ExtensionSource;
export type InstallLocation = "cli" | "global" | "project";

export async function installSource(
  source: ExtensionSource,
  type: ExtensionType,
  location: InstallLocation,
  cwd: string,                  // needed for project-local installs
): Promise<string>;
export function isRemoteSource(specifier: string): boolean;
export function getInstallDir(type: ExtensionType, location: InstallLocation, cwd: string): string;

Key functions:

• parseNpmSpecifier(spec): Parse npm:@scope/pkg@1.2.3 → { name, version }
• parseGitSpecifier(spec): Parse git:url@tag or git:url#branch
• installNpmPackage(name, version, targetDir): npm pack + extract + npm install
• installGitRepo(url, ref, targetDir): git clone + checkout + npm install
• getTargetDir(type, ephemeral): Returns temp dir or agent dir based on source

src/core/extensions/scanner.ts

Unified recursive scanning for all extension types.

export function scanDirectory(
  baseDir: string,
  config: ExtensionTypeConfig,
): DiscoveredExtension[];

export function resolveEntryPoint(
  dir: string,
  config: ExtensionTypeConfig,
): string | null;

export function getRelativePath(
  absolutePath: string,
  baseDir: string,
  config: ExtensionTypeConfig,
): string;  // strips entry point filename and extension

src/core/extensions/filter.ts

Filter logic using glob patterns with ! exclusion. Matches against extension.path.

export function applyFilter(
  extensions: DiscoveredExtension[],
  patterns: string[],
): DiscoveredExtension[];

export function parseFilterPatterns(patterns: string[]): {
  include: string[];
  exclude: string[];
};

export function matchesPattern(path: string, pattern: string): boolean;

src/core/extensions/loader.ts

Main entry point coordinating the full loading flow.

export interface LoadExtensionsOptions {
  type: ExtensionType;
  cwd: string;
  agentDir: string;
  globalPaths: string[];              // from global settings.json → install to agentDir
  projectPaths: string[];             // from project settings.json → install to cwd/.pi/
  cliPaths: string[];                 // from CLI flags → install to /tmp/
  filter: string[];                   // combined filter patterns
}

export interface LoadExtensionsResult<T> {
  extensions: T[];
  errors: Array<{ path: string; error: string }>;
}

export async function discoverExtensions(
  options: LoadExtensionsOptions,
): Promise<DiscoveredExtension[]>;

src/core/extensions/index.ts

Public exports.

Modified Files

src/config.ts

Add directory getters:

export function getHooksDir(): string {
  return join(getAgentDir(), "hooks");
}

export function getSkillsDir(): string {
  return join(getAgentDir(), "skills");
}

// getToolsDir() already exists
// getThemesDir() = bundled themes (in package)
// getCustomThemesDir() = ~/.pi/agent/themes/ (user themes) - already exists

src/core/settings-manager.ts

Update Settings interface:

// Old:
hooks?: string[];
customTools?: string[];
skills?: SkillsSettings;

// New:
hooks?: ExtensionConfig;
tools?: ExtensionConfig;
skills?: ExtensionConfig;  // simplified from SkillsSettings
themes?: ExtensionConfig;

Add migration logic for old format:

function migrateSettings(settings: unknown): Settings {
  // Convert hooks: string[] → hooks: { paths: string[] }
  // Convert customTools: string[] → tools: { paths: string[] }
  // Convert skills.customDirectories → skills.paths
  // Convert skills.includeSkills/ignoredSkills → skills.filter
}

Add unified getters:

getExtensionConfig(type: ExtensionType): ExtensionConfig;
getExtensionPaths(type: ExtensionType): string[];
getExtensionFilter(type: ExtensionType): string[];

Update merge logic (paths are additive, filter overrides):

function mergeExtensionConfig(global: ExtensionConfig, project: ExtensionConfig): ExtensionConfig {
  return {
    paths: [...(global.paths ?? []), ...(project.paths ?? [])],  // additive
    filter: project.filter ?? global.filter,                      // override
  };
}

src/cli/args.ts

Update Args interface:

// Built-in tools (unchanged)
tools?: ToolName[];          // --tools read,bash,edit,write

// Source flags
hooks?: string[];            // --hook (existing, repeatable)
customTools?: string[];      // --tool (existing, repeatable)
skills?: string[];           // --skill (new, repeatable)
themes?: string[];           // --theme (new, repeatable)

// Filter flags
hooksFilter?: string[];      // --hooks "patterns"
customToolsFilter?: string[];// --custom-tools "patterns"
skillsFilter?: string[];     // --skills "patterns" (existing)
themesFilter?: string[];     // --themes "patterns"

// Disable flags
noHooks?: boolean;           // --no-hooks
noCustomTools?: boolean;     // --no-custom-tools
noSkills?: boolean;          // --no-skills (existing)

Update argument parsing:

// --tools (built-in tools, unchanged)
} else if (arg === "--tools" && i + 1 < args.length) {
  // ... existing logic for built-in tools

// --tool (add custom tool source)
} else if (arg === "--tool" && i + 1 < args.length) {
  result.customTools = result.customTools ?? [];
  result.customTools.push(args[++i]);

// --custom-tools (filter custom tools)
} else if (arg === "--custom-tools" && i + 1 < args.length) {
  result.customToolsFilter = args[++i].split(",").map(s => s.trim());

// --no-custom-tools
} else if (arg === "--no-custom-tools") {
  result.noCustomTools = true;

// --skill (add source) - new
} else if (arg === "--skill" && i + 1 < args.length) {
  result.skills = result.skills ?? [];
  result.skills.push(args[++i]);

// --theme (add source) - new  
} else if (arg === "--theme" && i + 1 < args.length) {
  result.themes = result.themes ?? [];
  result.themes.push(args[++i]);

// --themes (filter) - new
} else if (arg === "--themes" && i + 1 < args.length) {
  result.themesFilter = args[++i].split(",").map(s => s.trim());

// --hooks (filter) - new
} else if (arg === "--hooks" && i + 1 < args.length) {
  result.hooksFilter = args[++i].split(",").map(s => s.trim());

// --no-hooks - new
} else if (arg === "--no-hooks") {
  result.noHooks = true;

Add pi update command handling.

src/core/hooks/loader.ts

Refactor to use extension system:

import { discoverExtensions, type DiscoveredExtension } from "../extensions/index.js";

export async function discoverAndLoadHooks(
  options: {
    cwd: string;
    agentDir?: string;
    configuredPaths?: string[];
    cliPaths?: string[];
    filter?: string[];
  }
): Promise<LoadHooksResult> {
  const discovered = await discoverExtensions({
    type: "hooks",
    defaultDirs: [join(agentDir, "hooks"), join(cwd, ".pi", "hooks")],
    configuredPaths: options.configuredPaths ?? [],
    cliPaths: options.cliPaths ?? [],
    filter: options.filter ?? [],
  });

  // Load each discovered hook using existing jiti logic
  const results = await Promise.all(
    discovered.map(ext => loadHook(ext.entryPoint, cwd))
  );
  
  // ... rest of existing logic
}

Remove duplicate code:

• expandPath() → use from extensions/source-resolver.ts
• resolveHookPath() → use from extensions/scanner.ts
• Discovery logic → use discoverExtensions()

src/core/custom-tools/loader.ts

Same refactoring pattern as hooks/loader.ts.

src/core/skills.ts

Refactor loadSkills() and loadSkillsFromDir():

export function loadSkills(options: LoadSkillsOptions): LoadSkillsResult {
  const discovered = await discoverExtensions({
    type: "skills",
    defaultDirs: [
      // existing default dirs
      join(homedir(), ".codex", "skills"),
      join(homedir(), ".claude", "skills"),
      join(agentDir, "skills"),
      join(cwd, ".pi", "skills"),
    ],
    configuredPaths: options.paths ?? [],
    cliPaths: options.cliPaths ?? [],
    filter: options.filter ?? [],
  });

  // Load each discovered skill using existing parsing logic
  // ...
}

Remove:

• loadSkillsFromDirInternal() recursive logic → use scanner.ts
• matchesIncludePatterns()/matchesIgnorePatterns() → use filter.ts

src/modes/interactive/theme/theme.ts

Refactor getAvailableThemes() and loadThemeJson():

export function getAvailableThemes(): string[] {
  const discovered = discoverExtensions({
    type: "themes",
    defaultDirs: [getThemesDir(), getCustomThemesDir()],
    configuredPaths: settingsManager.getExtensionPaths("themes"),
    cliPaths: [],  // from args
    filter: settingsManager.getExtensionFilter("themes"),
  });

  return discovered.map(ext => ext.path);
}

src/core/sdk.ts

Update to pass new options structure:

// Hooks
const { hooks, errors } = await discoverAndLoadHooks({
  cwd,
  agentDir,
  configuredPaths: settingsManager.getExtensionPaths("hooks"),
  cliPaths: options.additionalHookPaths,
  filter: [...settingsManager.getExtensionFilter("hooks"), ...(options.hooksFilter ?? [])],
});

// Tools
const result = await discoverAndLoadCustomTools({
  cwd,
  agentDir,
  configuredPaths: settingsManager.getExtensionPaths("tools"),
  cliPaths: options.additionalToolPaths,
  filter: [...settingsManager.getExtensionFilter("tools"), ...(options.toolsFilter ?? [])],
  builtInToolNames: Object.keys(allTools),
});

src/modes/interactive/interactive-mode.ts

Update skill loading to use new options structure.

Migration & Backwards Compatibility

Settings Migration

When loading settings.json, detect old format and migrate:

// Old format detection
if (Array.isArray(settings.hooks)) {
  settings.hooks = { paths: settings.hooks };
}
if (Array.isArray(settings.customTools)) {
  settings.tools = { paths: settings.customTools };
  delete settings.customTools;
}
if (settings.skills?.customDirectories) {
  settings.skills.paths = settings.skills.customDirectories;
  delete settings.skills.customDirectories;
}
// ... etc

CLI Compatibility

• --tools with built-in tool names still works (detected by checking if values match known tool names)
• Alternatively, deprecation warning and suggest --builtin-tools

Implementation Order

1. Phase 1: Core extension framework

   • Create src/core/extensions/ directory
   • Implement types.ts, scanner.ts, filter.ts
   • Unit tests for scanning and filtering

2. Phase 2: Source resolution

   • Implement source-resolver.ts (npm + git)
   • Add npm pack and git clone logic
   • Unit tests for source parsing and installation

3. Phase 3: Settings migration

   • Update settings-manager.ts with new types
   • Add migration logic
   • Update config.ts with new directory getters

4. Phase 4: Refactor loaders

   • Refactor hooks/loader.ts
   • Refactor custom-tools/loader.ts
   • Refactor skills.ts
   • Refactor theme.ts
   • Remove duplicate code

5. Phase 5: CLI updates

   • Add new flags to args.ts
   • Update help text
   • Add pi update command

6. Phase 6: Integration

   • Update sdk.ts
   • Update interactive-mode.ts
   • End-to-end testing

7. Phase 7: Documentation

   • Update README.md
   • Update docs/hooks.md, docs/custom-tools.md
   • Add examples for npm/git extensions

Testing Strategy

Unit Tests

• test/extensions/scanner.test.ts: Directory scanning, entry point resolution
• test/extensions/filter.test.ts: Pattern matching, include/exclude logic
• test/extensions/source-resolver.test.ts: npm/git specifier parsing

Integration Tests

• test/extensions/npm-install.test.ts: Full npm package installation flow
• test/extensions/git-clone.test.ts: Full git repository cloning flow
• test/extensions/loading.test.ts: End-to-end extension discovery and loading

Migration Tests

• test/settings-migration.test.ts: Old → new settings format conversion

File Summary

New Files (7)

• src/core/extensions/types.ts
• src/core/extensions/source-resolver.ts
• src/core/extensions/scanner.ts
• src/core/extensions/filter.ts
• src/core/extensions/loader.ts
• src/core/extensions/index.ts
• docs/extension-loading.md (this file)

Modified Files (9)

• src/config.ts - add directory getters
• src/core/settings-manager.ts - new types, migration
• src/cli/args.ts - new flags, update parsing
• src/core/hooks/loader.ts - refactor to use extensions
• src/core/custom-tools/loader.ts - refactor to use extensions
• src/core/skills.ts - refactor to use extensions
• src/modes/interactive/theme/theme.ts - refactor to use extensions
• src/core/sdk.ts - update option passing
• src/modes/interactive/interactive-mode.ts - update skill loading

Deleted Code (moved to extensions/)

• Duplicate expandPath(), normalizeUnicodeSpaces() functions
• Duplicate discovery/scanning logic
• Duplicate path resolution logic