feat(config): template-config UI forms (configure sheet + editor)

Introduces the TemplateConfigSheet form and its view models, plus
the install-flow integration points: a new .awaitingConfig stage in
TemplateInstallerViewModel, the configureView step in the install
sheet, and the dashboard-header Configuration button wiring in
ProjectsView. This is the schemaful-template v2.3 UI that every
subsequent config commit builds on.

Originally landed alongside scaffolding for an iOS target in b289a83;
this is the split that keeps the template-config work and drops the
iOS scaffolding (the real iOS port is on scarf-mobile-development).

scarf/scarf/Features/Projects/Views/ProjectsView.swift

@@ -26,6 +26,7 @@ struct ProjectsView: View {
     @State private var showingInstallURLPrompt = false
     @State private var installURLInput = ""
     @State private var showingUninstallSheet = false
+    @State private var configEditorProject: ProjectEntry?
 
     private let uninstaller: ProjectTemplateUninstaller
 
@@ -36,6 +37,14 @@ struct ProjectsView: View {
         self.uninstaller = ProjectTemplateUninstaller(context: context)
     }
 
+    /// True when the given project has a cached manifest (i.e. was
+    /// installed from a schemaful template). Cheap — just a file
+    /// existence check via the transport.
+    private func isConfigurable(_ project: ProjectEntry) -> Bool {
+        let path = ProjectConfigService.manifestCachePath(for: project)
+        return serverContext.makeTransport().fileExists(path)
+    }
+
     @State private var selectedTab: DashboardTab = .dashboard
 
     var body: some View {

scarf/scarf/Features/Templates/ViewModels/TemplateConfigEditorViewModel.swift

@@ -0,0 +1,118 @@
+import Foundation
+import Observation
+import os
+
+/// Drives the post-install "Configuration" button on the project
+/// dashboard. Loads `<project>/.scarf/manifest.json` + `config.json`,
+/// hands a `TemplateConfigViewModel` seeded with current values to the
+/// sheet, then writes the edited values back on commit.
+///
+/// Smaller surface than `TemplateInstallerViewModel` — no unzipping,
+/// no parent-dir picking, no cron CLI. Just: read → edit → save.
+@Observable
+@MainActor
+final class TemplateConfigEditorViewModel {
+    private static let logger = Logger(subsystem: "com.scarf", category: "TemplateConfigEditorViewModel")
+
+    enum Stage: Sendable {
+        case idle
+        case loading
+        /// Manifest + config loaded; the sheet is displaying the form.
+        case editing
+        case saving
+        case succeeded
+        case failed(String)
+        /// Project wasn't installed from a schemaful template — no
+        /// manifest cache on disk. The dashboard button is hidden in
+        /// this case so we shouldn't hit this stage normally.
+        case notConfigurable
+    }
+
+    let context: ServerContext
+    let project: ProjectEntry
+    private let configService: ProjectConfigService
+
+    init(context: ServerContext, project: ProjectEntry) {
+        self.context = context
+        self.project = project
+        self.configService = ProjectConfigService(context: context)
+    }
+
+    var stage: Stage = .idle
+    var manifest: ProjectTemplateManifest?
+    var currentValues: [String: TemplateConfigValue] = [:]
+
+    /// Non-nil while `.editing`; used to construct the sheet's VM.
+    var formViewModel: TemplateConfigViewModel?
+
+    /// Load the cached manifest + current config values, then move to
+    /// `.editing` so the sheet can render the form.
+    func begin() {
+        stage = .loading
+        let service = configService
+        let project = project
+        Task.detached { [weak self] in
+            do {
+                guard let cachedManifest = try service.loadCachedManifest(project: project),
+                      let schema = cachedManifest.config,
+                      !schema.isEmpty else {
+                    await MainActor.run { [weak self] in
+                        self?.stage = .notConfigurable
+                    }
+                    return
+                }
+                let configFile = try service.load(project: project)
+                await MainActor.run { [weak self] in
+                    guard let self else { return }
+                    self.manifest = cachedManifest
+                    self.currentValues = configFile?.values ?? [:]
+                    self.formViewModel = TemplateConfigViewModel(
+                        schema: schema,
+                        templateId: cachedManifest.id,
+                        templateSlug: cachedManifest.slug,
+                        initialValues: self.currentValues,
+                        mode: .edit(project: project)
+                    )
+                    self.stage = .editing
+                }
+            } catch {
+                Self.logger.error("couldn't load config for \(project.path, privacy: .public): \(error.localizedDescription, privacy: .public)")
+                await MainActor.run { [weak self] in
+                    self?.stage = .failed(error.localizedDescription)
+                }
+            }
+        }
+    }
+
+    /// Called when the sheet's commit succeeded. Persists the edited
+    /// values to `<project>/.scarf/config.json`. Secrets are already
+    /// in the Keychain — the VM's commit step wrote them.
+    func save(values: [String: TemplateConfigValue]) {
+        guard let manifest else { return }
+        stage = .saving
+        let service = configService
+        let project = project
+        Task.detached { [weak self] in
+            do {
+                try service.save(
+                    project: project,
+                    templateId: manifest.id,
+                    values: values
+                )
+                await MainActor.run { [weak self] in
+                    self?.stage = .succeeded
+                }
+            } catch {
+                Self.logger.error("couldn't save config for \(project.path, privacy: .public): \(error.localizedDescription, privacy: .public)")
+                await MainActor.run { [weak self] in
+                    self?.stage = .failed(error.localizedDescription)
+                }
+            }
+        }
+    }
+
+    func cancel() {
+        stage = .idle
+        formViewModel = nil
+    }
+}

scarf/scarf/Features/Templates/ViewModels/TemplateConfigViewModel.swift

@@ -0,0 +1,198 @@
+import Foundation
+import Observation
+import os
+
+/// Drives the configure form for template install + post-install editing.
+///
+/// **Timing of secret storage.** The VM keeps freshly-entered secret bytes
+/// in-memory (`pendingSecrets`) until the user clicks the commit button.
+/// Only then does `commit()` push each secret through
+/// `ProjectConfigService.storeSecret` and get back a `keychainRef` URI.
+/// This means cancelling the sheet never leaves an orphan Keychain
+/// entry behind — the form is transactional from the user's POV.
+///
+/// **Validation.** Runs via `ProjectConfigService.validateValues` every
+/// time the user attempts to commit. Per-field errors are tracked in
+/// `errors` so the sheet can surface them inline with the offending field.
+/// No live validation on every keystroke — that creates a messy
+/// "error appears the moment you start typing" UX.
+@Observable
+@MainActor
+final class TemplateConfigViewModel {
+    private static let logger = Logger(subsystem: "com.scarf", category: "TemplateConfigViewModel")
+
+    enum Mode: Sendable {
+        /// User is filling in values for the first time as part of the
+        /// install flow. Secrets will be written to the Keychain when
+        /// `commit` succeeds.
+        case install
+        /// User is editing values for an already-installed project.
+        /// Existing keychain refs are preserved for fields the user
+        /// doesn't touch; only secrets the user actually changes get
+        /// re-written to the Keychain.
+        case edit(project: ProjectEntry)
+    }
+
+    let schema: TemplateConfigSchema
+    let templateId: String
+    let templateSlug: String
+    let mode: Mode
+    private let configService: ProjectConfigService
+
+    /// Current form values, keyed by field key. Non-secret values live
+    /// here directly; secret fields either hold a `.keychainRef(...)`
+    /// (existing, untouched in edit mode) or nothing at all (user
+    /// hasn't entered a secret yet, or they just cleared it).
+    var values: [String: TemplateConfigValue] = [:]
+
+    /// Raw secret bytes waiting to be written to the Keychain on
+    /// `commit()`. Indexed by field key. `values[key]` stays as its
+    /// current `.keychainRef(...)` (for edit mode) or missing (for
+    /// install mode) until commit swaps it for the freshly-written
+    /// ref URI.
+    var pendingSecrets: [String: Data] = [:]
+
+    /// One error per field with a problem. Populated by `commit()` on
+    /// validation failure; the sheet surfaces the message inline below
+    /// the offending control.
+    var errors: [String: String] = [:]
+
+    init(
+        schema: TemplateConfigSchema,
+        templateId: String,
+        templateSlug: String,
+        initialValues: [String: TemplateConfigValue] = [:],
+        mode: Mode,
+        configService: ProjectConfigService = ProjectConfigService()
+    ) {
+        self.schema = schema
+        self.templateId = templateId
+        self.templateSlug = templateSlug
+        self.mode = mode
+        self.configService = configService
+        self.values = Self.applyDefaults(schema: schema, initial: initialValues)
+    }
+
+    // MARK: - Field setters (the sheet calls these as controls change)
+
+    func setString(_ key: String, _ value: String) {
+        values[key] = .string(value)
+        errors.removeValue(forKey: key)
+    }
+
+    func setNumber(_ key: String, _ value: Double) {
+        values[key] = .number(value)
+        errors.removeValue(forKey: key)
+    }
+
+    func setBool(_ key: String, _ value: Bool) {
+        values[key] = .bool(value)
+        errors.removeValue(forKey: key)
+    }
+
+    func setList(_ key: String, _ items: [String]) {
+        values[key] = .list(items)
+        errors.removeValue(forKey: key)
+    }
+
+    /// Stage a new secret value. Doesn't hit the Keychain until
+    /// `commit()`. An empty `value` clears both the pending secret and
+    /// the field's stored keychainRef — only valid in edit mode, where
+    /// "empty" means "I want to remove this secret."
+    func setSecret(_ key: String, _ value: String) {
+        if value.isEmpty {
+            pendingSecrets.removeValue(forKey: key)
+            values.removeValue(forKey: key)
+        } else {
+            pendingSecrets[key] = Data(value.utf8)
+            // Keep any existing ref around; the sheet can display
+            // "(changed)" while the ref is still the old one. commit()
+            // overwrites on disk.
+        }
+        errors.removeValue(forKey: key)
+    }
+
+    // MARK: - Commit
+
+    /// Validate, persist secrets to the Keychain, and hand back the
+    /// final values dictionary. On validation failure, `errors` is
+    /// populated and the method returns `nil` without touching the
+    /// Keychain — the form is transactional.
+    ///
+    /// In install mode, `project` is required (secrets need a path
+    /// hash for their Keychain account). In edit mode it falls out of
+    /// the `.edit(project:)` associated value.
+    func commit(project: ProjectEntry? = nil) -> [String: TemplateConfigValue]? {
+        // Build the value set we're about to validate. For secrets
+        // that have a pending update, we treat them as present (we'll
+        // write them in a moment); for secrets already stored as
+        // keychainRef, we treat them as present too. Only a completely
+        // empty secret field is "missing."
+        var candidate = values
+        for key in pendingSecrets.keys {
+            // The field is about to have a fresh keychainRef — for
+            // validation purposes, use a placeholder ref so the type
+            // check passes. The real ref replaces it below.
+            candidate[key] = .keychainRef("pending://\(key)")
+        }
+        let validationErrors = ProjectConfigService.validateValues(candidate, against: schema)
+        guard validationErrors.isEmpty else {
+            var byField: [String: String] = [:]
+            for err in validationErrors {
+                guard let key = err.fieldKey else { continue }
+                byField[key] = err.message
+            }
+            self.errors = byField
+            return nil
+        }
+
+        // Validation passed — write the pending secrets to the Keychain.
+        let targetProject: ProjectEntry
+        switch mode {
+        case .install:
+            guard let project else {
+                Self.logger.error("commit(project:) called in install mode without a project")
+                return nil
+            }
+            targetProject = project
+        case .edit(let proj):
+            targetProject = proj
+        }
+
+        for (key, secret) in pendingSecrets {
+            do {
+                let ref = try configService.storeSecret(
+                    templateSlug: templateSlug,
+                    fieldKey: key,
+                    project: targetProject,
+                    secret: secret
+                )
+                values[key] = ref
+            } catch {
+                Self.logger.error("failed to store secret for \(key, privacy: .public): \(error.localizedDescription, privacy: .public)")
+                errors[key] = "Couldn't save secret to the Keychain: \(error.localizedDescription)"
+                return nil
+            }
+        }
+        pendingSecrets.removeAll()
+        errors.removeAll()
+        return values
+    }
+
+    // MARK: - Helpers
+
+    /// Seed the form with any author-supplied defaults for fields that
+    /// don't already have an initial value (from a saved config.json).
+    nonisolated private static func applyDefaults(
+        schema: TemplateConfigSchema,
+        initial: [String: TemplateConfigValue]
+    ) -> [String: TemplateConfigValue] {
+        var out = initial
+        for field in schema.fields where out[field.key] == nil {
+            if let def = field.defaultValue {
+                out[field.key] = def
+            }
+        }
+        return out
+    }
+}

scarf/scarf/Features/Templates/ViewModels/TemplateInstallerViewModel.swift

@@ -18,6 +18,10 @@ final class TemplateInstallerViewModel {
         case fetching(sourceDescription: String)
         case inspecting
         case awaitingParentDirectory
+        /// Template declared a non-empty config schema; the sheet
+        /// presents `TemplateConfigSheet` before continuing to the
+        /// preview. Schema-less templates skip this stage entirely.
+        case awaitingConfig
         case planned
         case installing
         case succeeded(installed: ProjectEntry)
@@ -139,14 +143,20 @@ final class TemplateInstallerViewModel {
         guard let inspection else { return }
         chosenParentDirectory = parentDir
         let service = templateService
-        let context = context
         Task.detached { [weak self] in
             do {
                 let plan = try service.buildPlan(inspection: inspection, parentDir: parentDir)
-                _ = context
                 await MainActor.run { [weak self] in
-                    self?.plan = plan
-                    self?.stage = .planned
+                    guard let self else { return }
+                    self.plan = plan
+                    // If the template declares a non-empty config
+                    // schema, insert the configure step before the
+                    // preview sheet. Otherwise go straight to .planned.
+                    if let schema = plan.configSchema, !schema.isEmpty {
+                        self.stage = .awaitingConfig
+                    } else {
+                        self.stage = .planned
+                    }
                 }
             } catch {
                 await MainActor.run { [weak self] in
@@ -156,6 +166,26 @@ final class TemplateInstallerViewModel {
         }
     }
 
+    /// Called by `TemplateInstallSheet` once the user has filled in
+    /// the configure form and `TemplateConfigViewModel.commit()`
+    /// succeeded. Stashes the values in the plan and advances to the
+    /// preview stage (`.planned`). Secrets in `values` are already
+    /// `.keychainRef(...)` — the VM's commit step wrote them to the
+    /// Keychain.
+    func submitConfig(values: [String: TemplateConfigValue]) {
+        guard var plan else { return }
+        plan.configValues = values
+        self.plan = plan
+        stage = .planned
+    }
+
+    /// Called when the user cancels out of the configure step without
+    /// committing. Returns to `.awaitingParentDirectory` so they can
+    /// try again (or dismiss the whole sheet).
+    func cancelConfig() {
+        stage = .awaitingParentDirectory
+    }
+
     func confirmInstall() {
         guard let plan else { return }
         stage = .installing

scarf/scarf/Features/Templates/Views/TemplateConfigSheet.swift

@@ -0,0 +1,384 @@
+import SwiftUI
+
+/// The configure form rendered for template install + post-install
+/// editing. One row per schema field; controls dispatch by field type.
+/// Commit button returns the finalized values via `onCommit` — in
+/// install mode the caller stashes them in the install plan; in edit
+/// mode the caller writes them straight to `<project>/.scarf/config.json`.
+struct TemplateConfigSheet: View {
+    @Environment(\.dismiss) private var dismiss
+
+    @State var viewModel: TemplateConfigViewModel
+    let title: LocalizedStringKey
+    let commitLabel: LocalizedStringKey
+    /// In install mode the caller passes the planned `ProjectEntry`
+    /// (project dir path is the unique key for the Keychain secret).
+    /// In edit mode the VM already holds the project; pass `nil` here.
+    let project: ProjectEntry?
+    let onCommit: ([String: TemplateConfigValue]) -> Void
+    let onCancel: () -> Void
+
+    var body: some View {
+        VStack(spacing: 0) {
+            header
+            Divider()
+            ScrollView {
+                VStack(alignment: .leading, spacing: 18) {
+                    if viewModel.schema.fields.isEmpty {
+                        ContentUnavailableView(
+                            "No fields",
+                            systemImage: "slider.horizontal.3",
+                            description: Text("This template has no configuration fields.")
+                        )
+                        .frame(maxWidth: .infinity, minHeight: 120)
+                    } else {
+                        ForEach(viewModel.schema.fields) { field in
+                            fieldRow(field)
+                        }
+                    }
+                    if let rec = viewModel.schema.modelRecommendation {
+                        modelRecommendation(rec)
+                    }
+                }
+                .padding(20)
+            }
+            Divider()
+            footer
+        }
+        .frame(minWidth: 560, minHeight: 480)
+    }
+
+    // MARK: - Header / footer
+
+    @ViewBuilder
+    private var header: some View {
+        HStack {
+            VStack(alignment: .leading, spacing: 2) {
+                Text(title).font(.title2.bold())
+                Text(viewModel.templateId)
+                    .font(.caption.monospaced())
+                    .foregroundStyle(.secondary)
+            }
+            Spacer()
+        }
+        .padding(16)
+    }
+
+    @ViewBuilder
+    private var footer: some View {
+        HStack {
+            Button("Cancel") {
+                onCancel()
+                dismiss()
+            }
+            .keyboardShortcut(.cancelAction)
+            Spacer()
+            Button(commitLabel) {
+                if let finalized = viewModel.commit(project: project) {
+                    onCommit(finalized)
+                    dismiss()
+                }
+            }
+            .keyboardShortcut(.defaultAction)
+            .buttonStyle(.borderedProminent)
+        }
+        .padding(16)
+    }
+
+    // MARK: - Field rows
+
+    @ViewBuilder
+    private func fieldRow(_ field: TemplateConfigField) -> some View {
+        VStack(alignment: .leading, spacing: 6) {
+            HStack(alignment: .firstTextBaseline, spacing: 4) {
+                Text(field.label).font(.headline)
+                if field.required {
+                    Text("*")
+                        .font(.headline)
+                        .foregroundStyle(.red)
+                }
+                Spacer()
+                Text(field.type.rawValue)
+                    .font(.caption2.monospaced())
+                    .foregroundStyle(.secondary)
+            }
+            if let description = field.description, !description.isEmpty {
+                Text(description)
+                    .font(.caption)
+                    .foregroundStyle(.secondary)
+                    .fixedSize(horizontal: false, vertical: true)
+            }
+            control(for: field)
+            if let err = viewModel.errors[field.key] {
+                Label(err, systemImage: "exclamationmark.triangle.fill")
+                    .font(.caption)
+                    .foregroundStyle(.red)
+            }
+        }
+        .padding(12)
+        .background(
+            RoundedRectangle(cornerRadius: 8)
+                .fill(.background.secondary)
+        )
+    }
+
+    @ViewBuilder
+    private func control(for field: TemplateConfigField) -> some View {
+        switch field.type {
+        case .string:
+            StringControl(
+                value: stringBinding(for: field),
+                placeholder: field.placeholder
+            )
+        case .text:
+            TextControl(value: stringBinding(for: field))
+        case .number:
+            NumberControl(value: numberBinding(for: field))
+        case .bool:
+            BoolControl(label: field.label, value: boolBinding(for: field))
+        case .enum:
+            EnumControl(
+                options: field.options ?? [],
+                value: stringBinding(for: field)
+            )
+        case .list:
+            ListControl(items: listBinding(for: field))
+        case .secret:
+            SecretControl(
+                fieldKey: field.key,
+                placeholder: field.placeholder,
+                viewModel: viewModel
+            )
+        }
+    }
+
+    // MARK: - Model recommendation panel
+
+    private func modelRecommendation(_ rec: TemplateModelRecommendation) -> some View {
+        VStack(alignment: .leading, spacing: 6) {
+            Label("Recommended model", systemImage: "lightbulb")
+                .font(.caption.bold())
+                .foregroundStyle(.secondary)
+            Text(rec.preferred).font(.body.monospaced())
+            if let rationale = rec.rationale, !rationale.isEmpty {
+                Text(rationale)
+                    .font(.caption)
+                    .foregroundStyle(.secondary)
+                    .fixedSize(horizontal: false, vertical: true)
+            }
+            if let alts = rec.alternatives, !alts.isEmpty {
+                Text("Also works: \(alts.joined(separator: ", "))")
+                    .font(.caption2)
+                    .foregroundStyle(.secondary)
+            }
+            Text("Scarf doesn't auto-switch your active model. Change it in Settings if you'd like.")
+                .font(.caption2)
+                .foregroundStyle(.tertiary)
+        }
+        .padding(12)
+        .background(
+            RoundedRectangle(cornerRadius: 8)
+                .fill(Color.accentColor.opacity(0.08))
+        )
+    }
+
+    // MARK: - Binding helpers (threading the VM through typed lenses)
+
+    private func stringBinding(for field: TemplateConfigField) -> Binding<String> {
+        Binding(
+            get: {
+                if case .string(let s) = viewModel.values[field.key] { return s }
+                return ""
+            },
+            set: { viewModel.setString(field.key, $0) }
+        )
+    }
+
+    private func numberBinding(for field: TemplateConfigField) -> Binding<Double> {
+        Binding(
+            get: {
+                if case .number(let n) = viewModel.values[field.key] { return n }
+                return 0
+            },
+            set: { viewModel.setNumber(field.key, $0) }
+        )
+    }
+
+    private func boolBinding(for field: TemplateConfigField) -> Binding<Bool> {
+        Binding(
+            get: {
+                if case .bool(let b) = viewModel.values[field.key] { return b }
+                return false
+            },
+            set: { viewModel.setBool(field.key, $0) }
+        )
+    }
+
+    private func listBinding(for field: TemplateConfigField) -> Binding<[String]> {
+        Binding(
+            get: {
+                if case .list(let items) = viewModel.values[field.key] { return items }
+                return []
+            },
+            set: { viewModel.setList(field.key, $0) }
+        )
+    }
+}
+
+// MARK: - Field controls
+
+private struct StringControl: View {
+    @Binding var value: String
+    let placeholder: String?
+    var body: some View {
+        TextField(placeholder ?? "", text: $value)
+            .textFieldStyle(.roundedBorder)
+    }
+}
+
+private struct TextControl: View {
+    @Binding var value: String
+    var body: some View {
+        TextEditor(text: $value)
+            .font(.body.monospaced())
+            .frame(minHeight: 80, maxHeight: 160)
+            .overlay(
+                RoundedRectangle(cornerRadius: 6)
+                    .stroke(.secondary.opacity(0.3))
+            )
+    }
+}
+
+private struct NumberControl: View {
+    @Binding var value: Double
+    var body: some View {
+        TextField("", value: $value, format: .number)
+            .textFieldStyle(.roundedBorder)
+    }
+}
+
+private struct BoolControl: View {
+    let label: String
+    @Binding var value: Bool
+    var body: some View {
+        Toggle(isOn: $value) {
+            Text(value ? "Enabled" : "Disabled")
+                .font(.caption)
+                .foregroundStyle(.secondary)
+        }
+    }
+}
+
+private struct EnumControl: View {
+    let options: [TemplateConfigField.EnumOption]
+    @Binding var value: String
+    var body: some View {
+        // Segmented for ≤ 4 options, dropdown otherwise — fits Scarf's
+        // existing settings UI.
+        if options.count <= 4 {
+            Picker("", selection: $value) {
+                ForEach(options) { opt in
+                    Text(opt.label).tag(opt.value)
+                }
+            }
+            .pickerStyle(.segmented)
+            .labelsHidden()
+        } else {
+            Picker("", selection: $value) {
+                ForEach(options) { opt in
+                    Text(opt.label).tag(opt.value)
+                }
+            }
+            .labelsHidden()
+        }
+    }
+}
+
+/// Variable-length list of string values. Each row is a text field
+/// with an inline remove button; a + button adds a trailing row.
+private struct ListControl: View {
+    @Binding var items: [String]
+    var body: some View {
+        VStack(alignment: .leading, spacing: 4) {
+            ForEach(items.indices, id: \.self) { i in
+                HStack(spacing: 6) {
+                    TextField("", text: Binding(
+                        get: { i < items.count ? items[i] : "" },
+                        set: { newValue in
+                            guard i < items.count else { return }
+                            items[i] = newValue
+                        }
+                    ))
+                    .textFieldStyle(.roundedBorder)
+                    Button {
+                        guard i < items.count else { return }
+                        items.remove(at: i)
+                    } label: {
+                        Image(systemName: "minus.circle")
+                    }
+                    .buttonStyle(.borderless)
+                    .disabled(items.count <= 1)
+                }
+            }
+            Button {
+                items.append("")
+            } label: {
+                Label("Add", systemImage: "plus.circle")
+                    .font(.caption)
+            }
+            .buttonStyle(.borderless)
+        }
+    }
+}
+
+/// Secret fields never echo the previously-stored value back. Instead
+/// we render "(unchanged)" when a Keychain ref already exists and let
+/// the user type over it if they want to replace. Empty input in edit
+/// mode signals "remove this secret entirely."
+private struct SecretControl: View {
+    let fieldKey: String
+    let placeholder: String?
+    @Bindable var viewModel: TemplateConfigViewModel
+
+    @State private var typedValue: String = ""
+    @State private var isRevealed: Bool = false
+
+    private var hasStoredRef: Bool {
+        if case .keychainRef = viewModel.values[fieldKey] { return true }
+        return false
+    }
+
+    var body: some View {
+        VStack(alignment: .leading, spacing: 4) {
+            HStack(spacing: 6) {
+                Group {
+                    if isRevealed {
+                        TextField(placeholder ?? "", text: $typedValue)
+                    } else {
+                        SecureField(placeholder ?? "", text: $typedValue)
+                    }
+                }
+                .textFieldStyle(.roundedBorder)
+                .onChange(of: typedValue) { _, new in
+                    viewModel.setSecret(fieldKey, new)
+                }
+                Button {
+                    isRevealed.toggle()
+                } label: {
+                    Image(systemName: isRevealed ? "eye.slash" : "eye")
+                }
+                .buttonStyle(.borderless)
+                .help(isRevealed ? "Hide" : "Show while typing")
+            }
+            if hasStoredRef && typedValue.isEmpty {
+                Text("Saved in Keychain — leave empty to keep the stored value.")
+                    .font(.caption2)
+                    .foregroundStyle(.secondary)
+            } else if !typedValue.isEmpty {
+                Text("Will be saved to the Keychain on commit.")
+                    .font(.caption2)
+                    .foregroundStyle(.secondary)
+            }
+        }
+    }
+}

scarf/scarf/Features/Templates/Views/TemplateInstallSheet.swift

@@ -21,6 +21,8 @@ struct TemplateInstallSheet: View {
                 progress("Inspecting template…")
             case .awaitingParentDirectory:
                 pickParentView
+            case .awaitingConfig:
+                configureView
             case .planned:
                 if let plan = viewModel.plan {
                     plannedView(plan: plan)
@@ -85,6 +87,39 @@ struct TemplateInstallSheet: View {
         }
     }
 
+    /// Configure step for schemaful templates. Inlines
+    /// `TemplateConfigSheet` into the install flow rather than pushing
+    /// a second sheet on top — keeps the user in one window. The
+    /// nested VM is created freshly each time `.awaitingConfig` is
+    /// entered so a Cancel + retry doesn't carry stale form state.
+    @ViewBuilder
+    private var configureView: some View {
+        if let plan = viewModel.plan,
+           let schema = plan.configSchema,
+           let manifest = viewModel.inspection?.manifest {
+            TemplateConfigSheet(
+                viewModel: TemplateConfigViewModel(
+                    schema: schema,
+                    templateId: manifest.id,
+                    templateSlug: manifest.slug,
+                    initialValues: plan.configValues,
+                    mode: .install
+                ),
+                title: "Configure \(manifest.name)",
+                commitLabel: "Continue",
+                project: ProjectEntry(name: plan.projectRegistryName, path: plan.projectDir),
+                onCommit: { values in
+                    viewModel.submitConfig(values: values)
+                },
+                onCancel: {
+                    viewModel.cancelConfig()
+                }
+            )
+        } else {
+            progress("Preparing…")
+        }
+    }
+
     private func plannedView(plan: TemplateInstallPlan) -> some View {
         VStack(alignment: .leading, spacing: 0) {
             manifestHeader(plan.manifest)
@@ -102,6 +137,9 @@ struct TemplateInstallSheet: View {
                     if plan.memoryAppendix != nil {
                         memorySection(plan: plan)
                     }
+                    if let schema = plan.configSchema, !schema.isEmpty {
+                        configurationSection(plan: plan, schema: schema)
+                    }
                     readmeSection
                 }
                 .padding(.vertical)
@@ -213,6 +251,50 @@ struct TemplateInstallSheet: View {
         }
     }
 
+    /// Configuration values the user entered in the configure step.
+    /// Secrets display masked so the preview never echoes a freshly
+    /// typed API key back on screen.
+    private func configurationSection(plan: TemplateInstallPlan, schema: TemplateConfigSchema) -> some View {
+        section(title: "Configuration", subtitle: "written to \(plan.projectDir)/.scarf/config.json") {
+            VStack(alignment: .leading, spacing: 4) {
+                ForEach(schema.fields) { field in
+                    HStack(alignment: .firstTextBaseline, spacing: 8) {
+                        Text(field.key)
+                            .font(.caption.monospaced())
+                            .foregroundStyle(.secondary)
+                            .frame(minWidth: 120, alignment: .leading)
+                        Text(displayValue(for: field, in: plan.configValues))
+                            .font(.caption)
+                            .lineLimit(1)
+                            .truncationMode(.tail)
+                    }
+                }
+            }
+        }
+    }
+
+    /// One-line display form for a value in the preview. Secrets are
+    /// always masked; lists show a count + first entry; strings are
+    /// truncated by `.lineLimit(1)` at the view level.
+    private func displayValue(
+        for field: TemplateConfigField,
+        in values: [String: TemplateConfigValue]
+    ) -> String {
+        switch field.type {
+        case .secret:
+            return values[field.key] == nil ? "(not set)" : "••••••• (Keychain)"
+        case .list:
+            if case .list(let items) = values[field.key] {
+                if items.isEmpty { return "(none)" }
+                if items.count == 1 { return items[0] }
+                return "\(items[0]) + \(items.count - 1) more"
+            }
+            return "(none)"
+        default:
+            return values[field.key]?.displayString ?? "(not set)"
+        }
+    }
+
     private var readmeSection: some View {
         Group {
             // The body is preloaded in the VM off MainActor when inspection