npx claudepluginhub charleswiltgen/axiom --plugin axiomThis skill uses the workspace's default tool permissions.
**Core principle**: Xcode MCP gives you programmatic IDE access. Use workflow loops, not isolated tool calls.
Provides Ktor server patterns for routing DSL, plugins (auth, CORS, serialization), Koin DI, WebSockets, services, and testApplication testing.
Conducts multi-source web research with firecrawl and exa MCPs: searches, scrapes pages, synthesizes cited reports. For deep dives, competitive analysis, tech evaluations, or due diligence.
Provides demand forecasting, safety stock optimization, replenishment planning, and promotional lift estimation for multi-location retailers managing 300-800 SKUs.
Core principle: Xcode MCP gives you programmatic IDE access. Use workflow loops, not isolated tool calls.
Most tools require a tabIdentifier. Always call XcodeListWindows first.
1. XcodeListWindows → list of (tabIdentifier, workspacePath) pairs
2. Match workspacePath to your project
3. Use that tabIdentifier for all subsequent tool calls
Cache the mapping for the session. Only re-fetch if:
If XcodeListWindows returns empty: Xcode has no project open. Ask the user to open their project.
Iteratively build, diagnose, and fix until the project compiles.
1. BuildProject(tabIdentifier)
2. Check buildResult — if success, done
3. GetBuildLog(tabIdentifier) → parse errors
4. XcodeListNavigatorIssues(tabIdentifier) → canonical diagnostics
5. XcodeUpdate(file, fix) for each diagnostic
6. Go to step 1 (max 5 iterations)
7. If same error persists after 3 attempts → fall back to axiom-xcode-debugging
Why XcodeListNavigatorIssues over build log parsing: The Issue Navigator provides structured, deduplicated diagnostics. Build logs contain raw compiler output with noise.
When to fall back to axiom-xcode-debugging: When the error is environmental (zombie processes, stale Derived Data, simulator issues) rather than code-level. MCP tools operate on code; environment issues need CLI diagnostics.
Fast iteration on failing tests.
1. GetTestList(tabIdentifier) → discover available tests
2. RunSomeTests(tabIdentifier, [specific failing tests]) for fast iteration
3. Parse failures → identify code to fix
4. XcodeUpdate(file, fix) to patch code
5. Go to step 2 (max 5 iterations per test)
6. RunAllTests(tabIdentifier) as final verification
Why RunSomeTests first: Running a single test takes seconds. Running all tests takes minutes. Iterate on the failing test, then verify the full suite once it passes.
Parsing test results: Look for testResult field in the response. Failed tests include failure messages with file paths and line numbers.
Render SwiftUI previews and verify UI changes visually.
1. RenderPreview(tabIdentifier, sourceFilePath, previewDefinitionIndexInFile: 0) → image artifact
2. Review the rendered image for correctness
3. If making changes: XcodeUpdate → RenderPreview again
4. Compare before/after for regressions
Use cases: Verifying layout changes, checking dark mode appearance, confirming Liquid Glass effects render correctly.
Use Xcode's Issue Navigator as the canonical diagnostics source.
1. XcodeListNavigatorIssues(tabIdentifier) → all current issues
2. For specific files: XcodeRefreshCodeIssuesInFile(tabIdentifier, file)
3. Prioritize: errors > warnings > notes
4. Fix errors first, rebuild, re-check
Why this over grep-for-errors: The Issue Navigator tracks live diagnostics including type-check errors, missing imports, and constraint issues that only Xcode's compiler frontend surfaces.
Query Apple's documentation corpus through MCP.
1. DocumentationSearch(query) → documentation results
2. Cross-reference with axiom-apple-docs for bundled Xcode guides
Note: DocumentationSearch searches Apple's online documentation and WWDC transcripts. For the 20 for-LLM guides bundled inside Xcode, use axiom-apple-docs instead.
| Operation | Tool | Notes |
|---|---|---|
| Read file contents | XcodeRead | Sees Xcode's project view (generated files, resolved packages) |
| Create new file | XcodeWrite | Creates file — auto-adds to project structure |
| Edit existing file | XcodeUpdate | str_replace-style patches — safer than full rewrites |
| Search for files | XcodeGlob | Pattern matching within the project |
| Search file contents | XcodeGrep | Content search with line numbers |
| List directory | XcodeLS | Directory listing |
| Create directory | XcodeMakeDir | Creates directories |
| Operation | Tool | Risk |
|---|---|---|
| Delete file/directory | XcodeRM | Moves to Trash by default (deleteFiles: true) — confirm with user |
| Move/rename file | XcodeMV | May break imports and references |
Always confirm destructive operations with the user before calling XcodeRM or XcodeMV.
| Scenario | Use MCP | Use Standard (Read/Write/Grep) |
|---|---|---|
| Files in the Xcode project view | Yes — includes generated/resolved files | May miss generated files |
| Files outside the project | No | Yes — standard tools work everywhere |
| Need build context (diagnostics after edit) | Yes — edit + rebuild in one workflow | No build integration |
| Simple file read/edit | Either works | Slightly faster (no MCP overhead) |
ExecuteSnippet(tabIdentifier, codeSnippet: "print(MyModel.self)", sourceFilePath: "Sources/MyModel.swift")
Runs code in the context of a specific Swift file — has access to that file's fileprivate declarations. Not a generic REPL. No language parameter (Swift only).
Tab identifiers become invalid when:
Fix: Re-call XcodeListWindows to get fresh identifiers.
XcodeWrite — creates a new file. Fails if file exists (in some clients).XcodeUpdate — patches an existing file with oldString/newString replacement. One replacement per call (use replaceAll: true for all occurrences).Common mistake: Using XcodeWrite to edit an existing file overwrites its entire contents. Use XcodeUpdate for edits.
Xcode's mcpbridge has a known MCP spec violation: it populates content but omits structuredContent when tools declare outputSchema. This breaks strict MCP clients (Cursor, some Zed configurations).
Workaround: Use XcodeMCPWrapper as a proxy for strict clients.
After XcodeUpdate, the project may need a build to surface new diagnostics. Don't assume edits are correct without rebuilding.
| Thought | Reality |
|---|---|
| "I'll just use xcodebuild" | MCP gives IDE state + navigator diagnostics + previews that CLI doesn't |
| "Read tool works fine for Xcode files" | XcodeRead sees Xcode's project view including generated files and resolved packages |
| "Skip tab identifier, I only have one project" | Most tools fail silently without tabIdentifier — always call XcodeListWindows first |
| "Run all tests every time" | RunSomeTests for iteration, RunAllTests for verification — saves minutes per cycle |
| "I'll parse the build log for errors" | XcodeListNavigatorIssues provides structured, deduplicated diagnostics |
| "XcodeWrite to update a file" | XcodeUpdate for edits. XcodeWrite creates/overwrites. Wrong tool = data loss. |
| "One tool call is enough" | Workflows (BuildFix, TestFix) use loops. Isolated calls miss the iteration pattern. |
Skills: axiom-xcode-mcp-setup, axiom-xcode-mcp-ref, axiom-xcode-debugging