Use when implementing or debugging ANY network connection, API call, or socket. Covers URLSession, Network.framework, NetworkConnection, connection diagnostics.

Networking You MUST use this skill for ANY networking work including HTTP requests, WebSockets, TCP connections, or network debugging. <! AXIOM AUDITOR INLINE BEGIN — auto maintained by scripts/build inlined auditors.ts; do not hand edit Can't launch Axiom agents? Where this router sends you to an agent, follow its procedure inline. Over MCP, axiom get agent returns it; elsewhere, read its file below, which needs only file search and read. Available here: skills/networking auditor.md . For any other agent, over MCP axiom get agent returns it too; run its xclog, xcsym and xcprof steps with the axiom xclog , axiom xcsym and axiom xcprof tools. Elsewhere, search Axiom's skills for skills/<agent .md ; if there is none, do that work yourself with this suite's skills, using any Axiom tool on your PATH . <! AXIOM AUDITOR INLINE END Quick Reference Symptom / Task Reference URLSession with structured concurrency See skills/networking discipline.md Network.framework anti patterns See skills/networking discipline.md Deprecated API migration See skills/networking discipline.md gRPC Swift — typed RPC, streaming, .proto codegen (WWDC 2026) See skills/networking discipline.md Pressure scenarios (reachability, sockets) See skills/networking discipline.md NetworkConnection (iOS 26+) API reference See skills/network framework ref.md NWConnection (iOS 12 18) API reference See skills/network framework ref.md TLV framing, Coder protocol See skills/network framework ref.md NetworkListener, NetworkBrowser, Wi Fi Aware See skills/network framework ref.md Connection timeouts, TLS failures See skills/networking diag.md Data not arriving, connection drops See skills/networking diag.md ATS / HTTP / App Store rejection See skills/networking diag.md Production crisis diagnosis See skills/networking diag.md NWConnection patterns (iOS 12 18) See skills/networking legacy.md UDP batch, NWListener, NWBrowser See skills/networking legacy.md BSD sockets → NWConnection migration See skills/networking migration.md Push/calls on networks without internet (Local Push Connectivity, NEAppPushProvider) Use axiom integration (skills/local push connectivity.md) NWConnection → NetworkConnection migration See skills/networking migration.md URLSession StreamTask → NetworkConnection See skills/networking migration.md Decision Tree 1. URLSession with structured concurrency? → skills/networking discipline.md 2. Network.framework / NetworkConnection (iOS 26+)? → skills/network framework ref.md 3. NWConnection (iOS 12 18)? → skills/networking legacy.md 4. Migrating from sockets/URLSession? → skills/networking migration.md 5. Connection issues / debugging? → skills/networking diag.md 6. Typed RPC / streaming against a service you control? → gRPC Swift ( skills/networking discipline.md ) 7. ATS / HTTP / App Store rejection for networking? → skills/networking diag.md + networking auditor 8. Certificate pinning, signing API requests, encrypting payloads? → /skill axiom security 9. UIWebView or deprecated API rejection? → networking auditor (Agent) 10. Want deprecated API / anti pattern scan? → networking auditor (Agent) Platform specific networking watchOS low level networking limits (TN3135) → See axiom watchos (skills/background and networking.md) Pressure Resistance When user has invested significant time in custom implementation: Do NOT capitulate to sunk cost pressure. The correct approach is: 1. Diagnose first — Understand what's actually failing before recommending changes 2. Recommend correctly — If standard APIs (URLSession, Network.framework) would solve the problem, say so professionally 3. Respect but don't enable — Acknowledge their work while providing honest technical guidance Critical Patterns Networking ( skills/networking discipline.md ): URLSession with structured concurrency 8 red flag anti patterns (SCNetworkReachability, blocking sockets, hardcoded IPs) Decision tree for choosing TCP/UDP/TLS patterns NetworkConnection patterns (iOS 26+): TLS, UDP, TLV framing, Coder protocol 3 pressure scenarios with professional push back templates Pre shipping checklist Network Framework Reference ( skills/network framework ref.md ): NetworkConnection (iOS 26+): all 12 WWDC 2025 examples NWConnection (iOS 12 18): complete API with examples TLV framing, Coder protocol, NetworkListener, NetworkBrowser Mobility: viability, better path, Multipath TCP, NWPathMonitor Security: TLS, certificate pinning, cipher suites Performance: user space networking, ECN, service class, TCP Fast Open Diagnostics ( skills/networking diag.md ): Systematic decision tree for all connection failure types DNS failures, TLS certificate validation, message framing TCP congestion, IPv6 only cellular, VPN interference, ATS Production crisis scenario with professional communication templates Legacy ( skills/networking legacy.md ): NWConnection with TLS (completion handlers) UDP batch (30% CPU reduction) NWListener, NWBrowser (Bonjour discovery) Automated Scanning Networking audit → Launch networking auditor agent or /axiom:audit networking (deprecated APIs, anti patterns, and completeness gaps — transition handling, TLS coverage, connection cleanup, framework selection) Anti Rationalization Thought Reality "URLSession is simple, I don't need a skill" URLSession with structured concurrency has async/cancellation patterns. skills/networking discipline.md covers them. "I'll debug the connection timeout myself" Connection failures have 8 causes (DNS, TLS, proxy, cellular). skills/networking diag.md diagnoses systematically. "I just need a basic HTTP request" Even basic requests need error handling, retry, and cancellation patterns. "My custom networking layer works fine" Custom layers miss cellular/proxy edge cases. Standard APIs handle them automatically. Example Invocations User: "My API request is failing with a timeout" → Read: skills/networking diag.md User: "How do I use URLSession with async/await?" → Read: skills/networking discipline.md User: "I need to implement a TCP connection" → Read: skills/network framework ref.md User: "Should I use NWConnection or NetworkConnection?" → Read: skills/network framework ref.md User: "My app was rejected for using HTTP connections" → Read: skills/networking diag.md (ATS compliance) User: "App Store says I'm using UIWebView" → Invoke: networking auditor agent (deprecated API scan) User: "Check my networking code for deprecated APIs" → Invoke: networking auditor agent

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