Apple Documentation Router

Apple bundles for-LLM markdown documentation inside Xcode. These are authoritative, up-to-date guides and diagnostics written by Apple engineers. Read them directly with Claude Code's native Read tool — no MCP server or special tool required.

When to Use

• You need the exact API signature or behavior from Apple
• An Axiom skill references an Apple framework and you want the official source
• A Swift compiler diagnostic needs explanation
• The user asks about a specific Apple framework feature

Priority: Axiom skills provide opinionated guidance (decision trees, anti-patterns, pressure scenarios). Apple docs provide authoritative API details. Use both together.

How to Read These Docs

The session-start hook resolves Xcode's location and echoes the literal base directories into session context (look for "Apple for-LLM Documentation: Xcode detected at <path>"). Use the Read tool with <that base>/<filename>.

Default Xcode location (/Applications/Xcode.app) base directories:

Content	Base directory
AdditionalDocumentation guides	/Applications/Xcode.app/Contents/PlugIns/IDEIntelligenceChat.framework/Versions/A/Resources/AdditionalDocumentation/
Swift compiler diagnostics	/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/share/doc/swift/diagnostics/

Example invocation Claude should produce:

Read /Applications/Xcode.app/Contents/PlugIns/IDEIntelligenceChat.framework/Versions/A/Resources/AdditionalDocumentation/SwiftUI-Implementing-Liquid-Glass-Design.md

Xcode-beta users: the session-start hook respects AXIOM_XCODE_PATH and reports the resolved path in session context — use that path, not the default above.

Guide Files (AdditionalDocumentation)

20 files. Read with the path pattern {guides base}/{filename}.

UI & Design

Topic	Filename
Liquid Glass in SwiftUI	SwiftUI-Implementing-Liquid-Glass-Design.md
Liquid Glass in UIKit	UIKit-Implementing-Liquid-Glass-Design.md
Liquid Glass in AppKit	AppKit-Implementing-Liquid-Glass-Design.md
Liquid Glass in WidgetKit	WidgetKit-Implementing-Liquid-Glass-Design.md
SwiftUI new toolbar features	SwiftUI-New-Toolbar-Features.md
SwiftUI styled text editing	SwiftUI-Styled-Text-Editing.md
SwiftUI WebKit integration	SwiftUI-WebKit-Integration.md
SwiftUI AlarmKit integration	SwiftUI-AlarmKit-Integration.md
Swift Charts 3D visualization	Swift-Charts-3D-Visualization.md
Foundation AttributedString updates	Foundation-AttributedString-Updates.md

Data & Persistence

Topic	Filename
SwiftData class inheritance	SwiftData-Class-Inheritance.md

Concurrency & Performance

Topic	Filename
Swift concurrency updates	Swift-Concurrency-Updates.md
InlineArray and Span	Swift-InlineArray-Span.md

Apple Intelligence

Topic	Filename
Foundation Models (on-device LLM)	FoundationModels-Using-on-device-LLM-in-your-app.md

System Integration

Topic	Filename
App Intents updates	AppIntents-Updates.md
StoreKit updates	StoreKit-Updates.md
MapKit GeoToolbox PlaceDescriptors	MapKit-GeoToolbox-PlaceDescriptors.md
Widgets for visionOS	Widgets-for-visionOS.md

Accessibility

Topic	Filename
Assistive Access in iOS	Implementing-Assistive-Access-in-iOS.md

Computer Vision

Topic	Filename
Visual Intelligence in iOS	Implementing-Visual-Intelligence-in-iOS.md

Swift Compiler Diagnostics

46 files in the diagnostics directory. Read with the path pattern {diagnostics base}/{filename}.

Concurrency Diagnostics

Diagnostic	Filename
Actor-isolated call from nonisolated context	actor-isolated-call.md
Conformance isolation	conformance-isolation.md
Isolated conformances	isolated-conformances.md
Nonisolated nonsending by default	nonisolated-nonsending-by-default.md
Sendable closure captures	sendable-closure-captures.md
Sendable metatypes	sendable-metatypes.md
Explicit Sendable annotations	explicit-sendable-annotations.md
Sending closure risks data race	sending-closure-risks-data-race.md
Sending risks data race	sending-risks-data-race.md
Mutable global variable	mutable-global-variable.md
Preconcurrency import	preconcurrency-import.md
Dynamic exclusivity	dynamic-exclusivity.md
Exclusivity violation	exclusivity-violation.md

Type System Diagnostics

Diagnostic	Filename
Existential any	existential-any.md
Existential member access limitations	existential-member-access-limitations.md
Nominal types	nominal-types.md
Multiple inheritance	multiple-inheritance.md
Protocol type non-conformance	protocol-type-non-conformance.md
Opaque type inference	opaque-type-inference.md
Foreign reference type	foreign-reference-type.md

Build & Migration Diagnostics

Diagnostic	Filename
Deprecated declaration	deprecated-declaration.md
Error in future Swift version	error-in-future-swift-version.md
Strict language features	strict-language-features.md
Strict memory safety	strict-memory-safety.md
Implementation only deprecated	implementation-only-deprecated.md
Member import visibility	member-import-visibility.md
Missing module on known paths	missing-module-on-known-paths.md
Module not testable	module-not-testable.md
Module version missing	module-version-missing.md
Clang declaration import	clang-declaration-import.md
Availability unrecognized name	availability-unrecognized-name.md
Always-available domain	always-available-domain.md
Upcoming language features	upcoming-language-features.md
Unknown warning group	unknown-warning-group.md
Compilation caching	compilation-caching.md
Embedded restrictions	embedded-restrictions.md

Swift Language Diagnostics

Diagnostic	Filename
Dynamic callable requirements	dynamic-callable-requirements.md
Property wrapper requirements	property-wrapper-requirements.md
Result builder methods	result-builder-methods.md
String interpolation conformance	string-interpolation-conformance.md
Trailing closure matching	trailing-closure-matching.md
Temporary pointers	temporary-pointers.md
Semantic copies	semantic-copies.md
Performance hints	performance-hints.md

Index

Diagnostic	Filename
Diagnostic groups (taxonomy)	diagnostic-groups.md
All diagnostics index	diagnostics.md

If a diagnostic you need isn't listed above, list the diagnostics directory first:

ls $AXIOM_XCODE_PATH/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/share/doc/swift/diagnostics/

Filenames follow the diagnostic's short name (lowercase, hyphenated).

Routing Decision Tree

User question about Apple API/framework?
├── Specific compiler error/warning → Read {diagnostics base}/<diagnostic-name>.md
├── Liquid Glass implementation     → Read {guides base}/<Framework>-Implementing-Liquid-Glass-Design.md
├── Swift concurrency patterns      → Read {guides base}/Swift-Concurrency-Updates.md
├── Foundation Models / on-device AI → Read {guides base}/FoundationModels-Using-on-device-LLM-in-your-app.md
├── SwiftData features              → Read {guides base}/SwiftData-Class-Inheritance.md
├── StoreKit / IAP                  → Read {guides base}/StoreKit-Updates.md
├── App Intents / Siri              → Read {guides base}/AppIntents-Updates.md
├── Charts / visualization          → Read {guides base}/Swift-Charts-3D-Visualization.md
├── Text editing / AttributedString → Read {guides base}/SwiftUI-Styled-Text-Editing.md or Foundation-AttributedString-Updates.md
├── WebKit in SwiftUI               → Read {guides base}/SwiftUI-WebKit-Integration.md
├── Toolbar features                → Read {guides base}/SwiftUI-New-Toolbar-Features.md
└── Other                           → ls the base directory to see what's available

Fallback When Xcode Is Unavailable

If AXIOM_XCODE_PATH is unset, or the path doesn't exist, or the IDEIntelligenceChat.framework directory is missing (older Xcode), fall back to:

1. sosumi.ai (markdown mirror of developer.apple.com — see axiom-tools/apple-docs-research.md)
2. WebFetch of the equivalent developer.apple.com URL
3. Suggest installing the latest Xcode for full Apple docs coverage

Do not silently fail — tell the user when Xcode docs aren't available locally and which fallback you used.

MCP Convenience Path

Clients using axiom-mcp can also invoke axiom_read_skill with the legacy ID (e.g., apple-guide-swiftui-implementing-liquid-glass-design). The MCP server reads the same Xcode files and returns the same content. Both paths are supported — the file-Read path works everywhere; the MCP path is a convenience for catalog/search workflows.

Research Methodology

For WWDC transcript capture (Chrome auto-capture), sosumi.ai documentation access, and multi-session research workflows, see skills/apple-docs-research.md.

Resources

Skills: axiom-swiftui, axiom-concurrency, axiom-data, axiom-ai, axiom-integration