feat(provider-adapter): implement multi-provider abstraction layer (Phase 1)

Add provider types, registry, capabilities, and message adapter registry.
Rename sdk-messages→claude-messages, agent-runner→claude-runner,
ClaudeSession→AgentSession. Update Rust AgentQueryOptions with provider
and provider_config fields. Capability-driven AgentPane rendering.

v2/bterminal-core/src/sidecar.rs

@@ -12,6 +12,8 @@ use crate::event::EventSink;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct AgentQueryOptions {
+    #[serde(default = "default_provider")]
+    pub provider: String,
     pub session_id: String,
     pub prompt: String,
     pub cwd: Option<String>,
@@ -24,6 +26,13 @@ pub struct AgentQueryOptions {
     pub model: Option<String>,
     pub claude_config_dir: Option<String>,
     pub additional_directories: Option<Vec<String>>,
+    /// Provider-specific configuration blob (passed through to sidecar as-is)
+    #[serde(default)]
+    pub provider_config: serde_json::Value,
+}
+
+fn default_provider() -> String {
+    "claude".to_string()
 }
 
 /// Directories to search for sidecar scripts.
@@ -66,12 +75,13 @@ impl SidecarManager {
 
         log::info!("Starting sidecar: {} {}", cmd.program, cmd.args.join(" "));
 
-        // Build a clean environment stripping CLAUDE* vars to prevent
+        // Build a clean environment stripping provider-specific vars to prevent
-        // the SDK from detecting nesting when BTerminal is launched from a Claude Code terminal.
+        // SDKs from detecting nesting when BTerminal is launched from a provider terminal.
-        // Whitelist CLAUDE_CODE_EXPERIMENTAL_* so feature flags (e.g. agent teams) pass through.
+        // Per-provider prefixes: CLAUDE* (whitelist CLAUDE_CODE_EXPERIMENTAL_*),
+        // CODEX* and OLLAMA* for future providers.
         let clean_env: Vec<(String, String)> = std::env::vars()
             .filter(|(k, _)| {
-                !k.starts_with("CLAUDE") || k.starts_with("CLAUDE_CODE_EXPERIMENTAL_")
+                strip_provider_env_var(k)
             })
             .collect();
 
@@ -177,8 +187,23 @@ impl SidecarManager {
             return Err("Sidecar not ready".to_string());
         }
 
+        // Validate that the requested provider has a runner available
+        let runner_name = format!("{}-runner.mjs", options.provider);
+        let runner_exists = self
+            .config
+            .search_paths
+            .iter()
+            .any(|base| base.join("dist").join(&runner_name).exists());
+        if !runner_exists {
+            return Err(format!(
+                "No sidecar runner found for provider '{}' (expected {})",
+                options.provider, runner_name
+            ));
+        }
+
         let msg = serde_json::json!({
             "type": "query",
+            "provider": options.provider,
             "sessionId": options.session_id,
             "prompt": options.prompt,
             "cwd": options.cwd,
@@ -191,6 +216,7 @@ impl SidecarManager {
             "model": options.model,
             "claudeConfigDir": options.claude_config_dir,
             "additionalDirectories": options.additional_directories,
+            "providerConfig": options.provider_config,
         });
 
         self.send_message(&msg)
@@ -227,8 +253,16 @@ impl SidecarManager {
         *self.ready.lock().unwrap()
     }
 
+    /// Resolve a sidecar runner command. Uses the default claude-runner for startup.
+    /// Future providers will have their own runners (e.g. codex-runner.mjs).
     fn resolve_sidecar_command(&self) -> Result<SidecarCommand, String> {
-        // Single bundled .mjs works with both Deno and Node.js.
+        self.resolve_sidecar_for_provider("claude")
+    }
+
+    /// Resolve a sidecar command for a specific provider's runner file.
+    fn resolve_sidecar_for_provider(&self, provider: &str) -> Result<SidecarCommand, String> {
+        let runner_name = format!("{}-runner.mjs", provider);
+
         // Try Deno first (faster startup, better perf), fall back to Node.js.
         let has_deno = Command::new("deno")
             .arg("--version")
@@ -246,7 +280,7 @@ impl SidecarManager {
         let mut checked = Vec::new();
 
         for base in &self.config.search_paths {
-            let mjs_path = base.join("dist").join("agent-runner.mjs");
+            let mjs_path = base.join("dist").join(&runner_name);
             if mjs_path.exists() {
                 if has_deno {
                     return Ok(SidecarCommand {
@@ -279,13 +313,27 @@ impl SidecarManager {
             ""
         };
         Err(format!(
-            "Sidecar not found. Checked: {}{}",
+            "Sidecar not found for provider '{}'. Checked: {}{}",
+            provider,
             paths.join(", "),
             runtime_note,
         ))
     }
 }
 
+/// Returns true if the env var should be KEPT (not stripped).
+/// Strips CLAUDE*, CODEX*, OLLAMA* prefixes to prevent nesting detection.
+/// Whitelists CLAUDE_CODE_EXPERIMENTAL_* for feature flags.
+fn strip_provider_env_var(key: &str) -> bool {
+    if key.starts_with("CLAUDE_CODE_EXPERIMENTAL_") {
+        return true;
+    }
+    if key.starts_with("CLAUDE") || key.starts_with("CODEX") || key.starts_with("OLLAMA") {
+        return false;
+    }
+    true
+}
+
 impl Drop for SidecarManager {
     fn drop(&mut self) {
         let _ = self.shutdown();

v2/package.json

@@ -14,7 +14,7 @@
     "tauri:build": "cargo tauri build",
     "test": "vitest run",
     "test:e2e": "wdio run tests/e2e/wdio.conf.js",
-    "build:sidecar": "esbuild sidecar/agent-runner.ts --bundle --platform=node --format=esm --outfile=sidecar/dist/agent-runner.mjs"
+    "build:sidecar": "esbuild sidecar/claude-runner.ts --bundle --platform=node --format=esm --outfile=sidecar/dist/claude-runner.mjs"
   },
   "devDependencies": {
     "@sveltejs/vite-plugin-svelte": "^6.2.1",

v2/sidecar/claude-runner.ts

@@ -1,6 +1,6 @@
-// Agent Runner — Node.js sidecar entry point
+// Claude Runner — Node.js sidecar entry point for Claude Code provider
-// Spawned by Rust backend, communicates via stdio NDJSON
+// Spawned by Rust SidecarManager, communicates via stdio NDJSON
-// Uses @anthropic-ai/claude-agent-sdk for proper Claude session management
+// Uses @anthropic-ai/claude-agent-sdk for Claude session management
 
 import { stdin, stdout, stderr } from 'process';
 import { createInterface } from 'readline';

v2/sidecar/package.json

@@ -4,7 +4,7 @@
   "version": "0.1.0",
   "type": "module",
   "scripts": {
-    "build": "esbuild agent-runner.ts --bundle --platform=node --target=node20 --outfile=dist/agent-runner.mjs --format=esm"
+    "build": "esbuild claude-runner.ts --bundle --platform=node --target=node20 --outfile=dist/claude-runner.mjs --format=esm"
   },
   "devDependencies": {
     "esbuild": "0.25.4"

v2/src-tauri/tauri.conf.json

@@ -44,7 +44,7 @@
       "icons/icon.ico"
     ],
     "resources": [
-      "../sidecar/dist/agent-runner.mjs"
+      "../sidecar/dist/claude-runner.mjs"
     ],
     "category": "DeveloperTool",
     "shortDescription": "Multi-session Claude agent dashboard",

v2/src/App.svelte

@@ -5,6 +5,8 @@
   import { isDetachedMode, getDetachedConfig } from './lib/utils/detach';
   import { startAgentDispatcher, stopAgentDispatcher } from './lib/agent-dispatcher';
   import { startHealthTick, stopHealthTick, clearHealthTracking } from './lib/stores/health.svelte';
+  import { registerProvider } from './lib/providers/registry.svelte';
+  import { CLAUDE_PROVIDER } from './lib/providers/claude';
   import { loadWorkspace, getActiveTab, setActiveTab, setActiveProject, getEnabledProjects } from './lib/stores/workspace.svelte';
 
   // Workspace components
@@ -65,6 +67,7 @@
     getSetting('project_max_aspect').then(v => {
       if (v) document.documentElement.style.setProperty('--project-max-aspect', v);
     });
+    registerProvider(CLAUDE_PROVIDER);
     startAgentDispatcher();
     startHealthTick();
 

v2/src/lib/adapters/agent-bridge.ts

@@ -4,7 +4,10 @@
 import { invoke } from '@tauri-apps/api/core';
 import { listen, type UnlistenFn } from '@tauri-apps/api/event';
 
+import type { ProviderId } from '../providers/types';
+
 export interface AgentQueryOptions {
+  provider?: ProviderId;
   session_id: string;
   prompt: string;
   cwd?: string;
@@ -17,6 +20,7 @@ export interface AgentQueryOptions {
   model?: string;
   claude_config_dir?: string;
   additional_directories?: string[];
+  provider_config?: Record<string, unknown>;
   remote_machine_id?: string;
 }
 

v2/src/lib/adapters/claude-messages.test.ts

@@ -1,6 +1,6 @@
 import { describe, it, expect, vi, beforeEach } from 'vitest';
-import { adaptSDKMessage } from './sdk-messages';
+import { adaptSDKMessage } from './claude-messages';
-import type { InitContent, TextContent, ThinkingContent, ToolCallContent, ToolResultContent, StatusContent, CostContent } from './sdk-messages';
+import type { InitContent, TextContent, ThinkingContent, ToolCallContent, ToolResultContent, StatusContent, CostContent } from './claude-messages';
 
 // Mock crypto.randomUUID for deterministic IDs when uuid is missing
 beforeEach(() => {

v2/src/lib/adapters/claude-messages.ts

@@ -1,5 +1,5 @@
-// SDK Message Adapter — insulates UI from Claude Agent SDK wire format changes
+// Claude Message Adapter — transforms Claude Agent SDK wire format to internal AgentMessage format
-// This is the ONLY place that knows SDK internals.
+// This is the ONLY place that knows Claude SDK internals.
 
 export type AgentMessageType =
   | 'init'

v2/src/lib/adapters/message-adapters.ts

@@ -0,0 +1,29 @@
+// Message Adapter Registry — routes raw provider messages to the correct parser
+// Each provider registers its own adapter; the dispatcher calls adaptMessage()
+
+import type { AgentMessage } from './claude-messages';
+import type { ProviderId } from '../providers/types';
+import { adaptSDKMessage } from './claude-messages';
+
+/** Function signature for a provider message adapter */
+export type MessageAdapter = (raw: Record<string, unknown>) => AgentMessage[];
+
+const adapters = new Map<ProviderId, MessageAdapter>();
+
+/** Register a message adapter for a provider */
+export function registerMessageAdapter(providerId: ProviderId, adapter: MessageAdapter): void {
+  adapters.set(providerId, adapter);
+}
+
+/** Adapt a raw message using the appropriate provider adapter */
+export function adaptMessage(providerId: ProviderId, raw: Record<string, unknown>): AgentMessage[] {
+  const adapter = adapters.get(providerId);
+  if (!adapter) {
+    console.warn(`No message adapter for provider: ${providerId}, falling back to claude`);
+    return adaptSDKMessage(raw);
+  }
+  return adapter(raw);
+}
+
+// Register Claude adapter by default
+registerMessageAdapter('claude', adaptSDKMessage);

v2/src/lib/adapters/provider-bridge.ts

@@ -0,0 +1,26 @@
+// Provider Bridge — generic adapter that delegates to provider-specific bridges
+// Currently only Claude is implemented; future providers add their own bridge files
+
+import type { ProviderId } from '../providers/types';
+import { listProfiles as claudeListProfiles, listSkills as claudeListSkills, readSkill as claudeReadSkill, type ClaudeProfile, type ClaudeSkill } from './claude-bridge';
+
+// Re-export types for consumers
+export type { ClaudeProfile, ClaudeSkill };
+
+/** List profiles for a given provider (only Claude supports this) */
+export async function listProviderProfiles(provider: ProviderId): Promise<ClaudeProfile[]> {
+  if (provider === 'claude') return claudeListProfiles();
+  return [];
+}
+
+/** List skills for a given provider (only Claude supports this) */
+export async function listProviderSkills(provider: ProviderId): Promise<ClaudeSkill[]> {
+  if (provider === 'claude') return claudeListSkills();
+  return [];
+}
+
+/** Read a skill file (only Claude supports this) */
+export async function readProviderSkill(provider: ProviderId, path: string): Promise<string> {
+  if (provider === 'claude') return claudeReadSkill(path);
+  return '';
+}

v2/src/lib/agent-dispatcher.test.ts

@@ -51,8 +51,10 @@ vi.mock('./adapters/agent-bridge', () => ({
   restartAgent: (...args: unknown[]) => mockRestartAgent(...args),
 }));
 
-vi.mock('./adapters/sdk-messages', () => ({
+vi.mock('./providers/types', () => ({}));
-  adaptSDKMessage: vi.fn((raw: Record<string, unknown>) => {
+
+vi.mock('./adapters/message-adapters', () => ({
+  adaptMessage: vi.fn((_provider: string, raw: Record<string, unknown>) => {
     if (raw.type === 'system' && raw.subtype === 'init') {
       return [{
         id: 'msg-1',

v2/src/lib/agent-dispatcher.ts

@@ -2,8 +2,9 @@
 // Single listener that routes sidecar messages to the correct agent session
 
 import { onSidecarMessage, onSidecarExited, restartAgent, type SidecarMessage } from './adapters/agent-bridge';
-import { adaptSDKMessage } from './adapters/sdk-messages';
+import { adaptMessage } from './adapters/message-adapters';
-import type { InitContent, CostContent, ToolCallContent } from './adapters/sdk-messages';
+import type { InitContent, CostContent, ToolCallContent } from './adapters/claude-messages';
+import type { ProviderId } from './providers/types';
 import {
   updateAgentStatus,
   setAgentSdkSessionId,
@@ -34,14 +35,18 @@ let unlistenExit: (() => void) | null = null;
 // Map sessionId -> projectId for persistence routing
 const sessionProjectMap = new Map<string, string>();
 
+// Map sessionId -> provider for message adapter routing
+const sessionProviderMap = new Map<string, ProviderId>();
+
 // Map sessionId -> start timestamp for metrics
 const sessionStartTimes = new Map<string, number>();
 
 // In-flight persistence counter — prevents teardown from racing with async saves
 let pendingPersistCount = 0;
 
-export function registerSessionProject(sessionId: string, projectId: string): void {
+export function registerSessionProject(sessionId: string, projectId: string, provider: ProviderId = 'claude'): void {
   sessionProjectMap.set(sessionId, projectId);
+  sessionProviderMap.set(sessionId, provider);
 }
 
 // Sidecar liveness — checked by UI components
@@ -149,7 +154,8 @@ const SUBAGENT_TOOL_NAMES = new Set(['Agent', 'Task', 'dispatch_agent']);
 const toolUseToChildPane = new Map<string, string>();
 
 function handleAgentEvent(sessionId: string, event: Record<string, unknown>): void {
-  const messages = adaptSDKMessage(event);
+  const provider = sessionProviderMap.get(sessionId) ?? 'claude';
+  const messages = adaptMessage(provider, event);
 
   // Route messages with parentId to the appropriate child pane
   const mainMessages: typeof messages = [];
@@ -401,5 +407,6 @@ export function stopAgentDispatcher(): void {
   // Clear routing maps to prevent unbounded memory growth
   toolUseToChildPane.clear();
   sessionProjectMap.clear();
+  sessionProviderMap.clear();
   sessionStartTimes.clear();
 }

v2/src/lib/components/Agent/AgentPane.svelte

@@ -21,7 +21,8 @@
     CostContent,
     ErrorContent,
     StatusContent,
-  } from '../../adapters/sdk-messages';
+  } from '../../adapters/claude-messages';
+  import type { ProviderId, ProviderCapabilities } from '../../providers/types';
 
   // Tool-aware truncation limits
   const MAX_BASH_LINES = 500;
@@ -29,15 +30,28 @@
   const MAX_GLOB_LINES = 20;
   const MAX_DEFAULT_LINES = 30;
 
+  // Default capabilities (Claude — all enabled)
+  const DEFAULT_CAPABILITIES: ProviderCapabilities = {
+    hasProfiles: true,
+    hasSkills: true,
+    hasModelSelection: true,
+    hasSandbox: false,
+    supportsSubagents: true,
+    supportsCost: true,
+    supportsResume: true,
+  };
+
   interface Props {
     sessionId: string;
     prompt?: string;
     cwd?: string;
     profile?: string;
+    provider?: ProviderId;
+    capabilities?: ProviderCapabilities;
     onExit?: () => void;
   }
 
-  let { sessionId, prompt: initialPrompt = '', cwd: initialCwd, profile: profileName, onExit }: Props = $props();
+  let { sessionId, prompt: initialPrompt = '', cwd: initialCwd, profile: profileName, provider: providerId = 'claude', capabilities = DEFAULT_CAPABILITIES, onExit }: Props = $props();
 
   let session = $derived(getAgentSession(sessionId));
   let inputPrompt = $state(initialPrompt);
@@ -106,9 +120,10 @@
 
   onMount(async () => {
     await getHighlighter();
+    // Only load profiles/skills for providers that support them
     const [profileList, skillList] = await Promise.all([
-      listProfiles().catch(() => []),
+      capabilities.hasProfiles ? listProfiles().catch(() => []) : Promise.resolve([]),
-      listSkills().catch(() => []),
+      capabilities.hasSkills ? listSkills().catch(() => []) : Promise.resolve([]),
     ]);
     profiles = profileList;
     skills = skillList;
@@ -144,6 +159,7 @@
 
     const profile = profileName ? profiles.find(p => p.name === profileName) : undefined;
     await queryAgent({
+      provider: providerId,
       session_id: sessionId,
       prompt: text,
       cwd: initialCwd || undefined,
@@ -335,7 +351,7 @@
           {#if msg.type === 'init'}
             <div class="msg-init">
               <span class="label">Session started</span>
-              <span class="model">{(msg.content as import('../../adapters/sdk-messages').InitContent).model}</span>
+              <span class="model">{(msg.content as import('../../adapters/claude-messages').InitContent).model}</span>
             </div>
           {:else if msg.type === 'text'}
             {@const textContent = (msg.content as TextContent).text}
@@ -490,19 +506,21 @@
         </svg>
         New Session
       </button>
-      <button class="session-btn session-btn-continue" onclick={() => promptRef?.focus()}>
+      {#if capabilities.supportsResume}
-        <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+        <button class="session-btn session-btn-continue" onclick={() => promptRef?.focus()}>
-          <polyline points="9 18 15 12 9 6"></polyline>
+          <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-        </svg>
+            <polyline points="9 18 15 12 9 6"></polyline>
-        Continue
+          </svg>
-      </button>
+          Continue
+        </button>
+      {/if}
     </div>
   {/if}
 
   <!-- Unified prompt input -->
   <div class="prompt-container" class:disabled={isRunning}>
     <div class="prompt-wrapper">
-      {#if showSkillMenu && filteredSkills.length > 0}
+      {#if capabilities.hasSkills && showSkillMenu && filteredSkills.length > 0}
         <div class="skill-menu">
           {#each filteredSkills as skill, i (skill.name)}
             <button

v2/src/lib/components/Terminal/AgentPreviewPane.svelte

@@ -13,7 +13,7 @@
     ErrorContent,
     TextContent,
     AgentMessage,
-  } from '../../adapters/sdk-messages';
+  } from '../../adapters/claude-messages';
   import '@xterm/xterm/css/xterm.css';
 
   interface Props {

v2/src/lib/components/Workspace/AgentSession.svelte

@@ -16,7 +16,8 @@
     setAgentSdkSessionId,
     getAgentSession,
   } from '../../stores/agents.svelte';
-  import type { AgentMessage } from '../../adapters/sdk-messages';
+  import type { AgentMessage } from '../../adapters/claude-messages';
+  import { getProvider, getDefaultProviderId } from '../../providers/registry.svelte';
   import AgentPane from '../Agent/AgentPane.svelte';
 
   interface Props {
@@ -26,6 +27,9 @@
 
   let { project, onsessionid }: Props = $props();
 
+  let providerId = $derived(project.provider ?? getDefaultProviderId());
+  let providerMeta = $derived(getProvider(providerId));
+
   let sessionId = $state(crypto.randomUUID());
   let lastState = $state<ProjectAgentState | null>(null);
   let loading = $state(true);
@@ -35,7 +39,7 @@
     sessionId = crypto.randomUUID();
     hasRestoredHistory = false;
     lastState = null;
-    registerSessionProject(sessionId, project.id);
+    registerSessionProject(sessionId, project.id, providerId);
     trackProject(project.id, sessionId);
     onsessionid?.(sessionId);
   }
@@ -70,7 +74,7 @@
     } finally {
       loading = false;
       // Register session -> project mapping for persistence + health tracking
-      registerSessionProject(sessionId, project.id);
+      registerSessionProject(sessionId, project.id, providerId);
       trackProject(project.id, sessionId);
       onsessionid?.(sessionId);
     }
@@ -112,7 +116,7 @@
   }
 </script>
 
-<div class="claude-session">
+<div class="agent-session">
   {#if loading}
     <div class="loading-state">Loading session...</div>
   {:else}
@@ -120,13 +124,15 @@
       {sessionId}
       cwd={project.cwd}
       profile={project.profile || undefined}
+      provider={providerId}
+      capabilities={providerMeta?.capabilities}
       onExit={handleNewSession}
     />
   {/if}
 </div>
 
 <style>
-  .claude-session {
+  .agent-session {
     height: 100%;
     overflow: hidden;
     display: flex;

v2/src/lib/components/Workspace/ContextTab.svelte

@@ -1,6 +1,6 @@
 <script lang="ts">
   import { getAgentSession, getTotalCost, type AgentSession } from '../../stores/agents.svelte';
-  import type { AgentMessage, ToolCallContent, CostContent, CompactionContent } from '../../adapters/sdk-messages';
+  import type { AgentMessage, ToolCallContent, CostContent, CompactionContent } from '../../adapters/claude-messages';
   import { extractFilePaths } from '../../utils/tool-files';
 
   interface Props {

v2/src/lib/components/Workspace/ProjectBox.svelte

@@ -3,7 +3,7 @@
   import type { ProjectConfig } from '../../types/groups';
   import { PROJECT_ACCENTS } from '../../types/groups';
   import ProjectHeader from './ProjectHeader.svelte';
-  import ClaudeSession from './ClaudeSession.svelte';
+  import AgentSession from './AgentSession.svelte';
   import TerminalTabs from './TerminalTabs.svelte';
   import TeamAgentsPanel from './TeamAgentsPanel.svelte';
   import ProjectFiles from './ProjectFiles.svelte';
@@ -148,7 +148,7 @@
   <div class="project-content-area">
     <!-- PERSISTED-EAGER: always mounted, toggled via display -->
     <div class="content-pane" style:display={activeTab === 'model' ? 'flex' : 'none'}>
-      <ClaudeSession {project} onsessionid={(id) => mainSessionId = id} />
+      <AgentSession {project} onsessionid={(id) => mainSessionId = id} />
       {#if mainSessionId}
         <TeamAgentsPanel {mainSessionId} />
       {/if}

v2/src/lib/providers/claude.ts

@@ -0,0 +1,20 @@
+// Claude Provider — metadata and capabilities for Claude Code
+
+import type { ProviderMeta } from './types';
+
+export const CLAUDE_PROVIDER: ProviderMeta = {
+  id: 'claude',
+  name: 'Claude Code',
+  description: 'Anthropic Claude Code agent via SDK',
+  capabilities: {
+    hasProfiles: true,
+    hasSkills: true,
+    hasModelSelection: true,
+    hasSandbox: false,
+    supportsSubagents: true,
+    supportsCost: true,
+    supportsResume: true,
+  },
+  sidecarRunner: 'claude-runner.mjs',
+  defaultModel: 'claude-sonnet-4-20250514',
+};

v2/src/lib/providers/registry.svelte.ts

@@ -0,0 +1,26 @@
+// Provider Registry — singleton registry of available providers (Svelte 5 runes)
+
+import type { ProviderId, ProviderMeta } from './types';
+
+const providers = $state(new Map<ProviderId, ProviderMeta>());
+
+export function registerProvider(meta: ProviderMeta): void {
+  providers.set(meta.id, meta);
+}
+
+export function getProvider(id: ProviderId): ProviderMeta | undefined {
+  return providers.get(id);
+}
+
+export function getProviders(): ProviderMeta[] {
+  return Array.from(providers.values());
+}
+
+export function getDefaultProviderId(): ProviderId {
+  return 'claude';
+}
+
+/** Check if a specific provider is registered */
+export function hasProvider(id: ProviderId): boolean {
+  return providers.has(id);
+}

v2/src/lib/providers/types.ts

@@ -0,0 +1,34 @@
+// Provider abstraction types — defines the interface for multi-provider agent support
+
+export type ProviderId = 'claude' | 'codex' | 'ollama';
+
+/** What a provider can do — UI gates features on these flags */
+export interface ProviderCapabilities {
+  hasProfiles: boolean;
+  hasSkills: boolean;
+  hasModelSelection: boolean;
+  hasSandbox: boolean;
+  supportsSubagents: boolean;
+  supportsCost: boolean;
+  supportsResume: boolean;
+}
+
+/** Static metadata about a provider */
+export interface ProviderMeta {
+  id: ProviderId;
+  name: string;
+  description: string;
+  capabilities: ProviderCapabilities;
+  /** Name of the sidecar runner file (e.g. 'claude-runner.mjs') */
+  sidecarRunner: string;
+  /** Default model identifier, if applicable */
+  defaultModel?: string;
+}
+
+/** Per-provider configuration (stored in settings) */
+export interface ProviderSettings {
+  enabled: boolean;
+  defaultModel?: string;
+  /** Provider-specific config blob */
+  config: Record<string, unknown>;
+}

v2/src/lib/stores/agents.svelte.ts

@@ -1,7 +1,7 @@
 // Agent tracking state — Svelte 5 runes
 // Manages agent session lifecycle and message history
 
-import type { AgentMessage } from '../adapters/sdk-messages';
+import type { AgentMessage } from '../adapters/claude-messages';
 
 export type AgentStatus = 'idle' | 'starting' | 'running' | 'done' | 'error';
 

v2/src/lib/types/groups.ts

@@ -1,3 +1,5 @@
+import type { ProviderId } from '../providers/types';
+
 export interface ProjectConfig {
   id: string;
   name: string;
@@ -7,6 +9,8 @@ export interface ProjectConfig {
   cwd: string;
   profile: string;
   enabled: boolean;
+  /** Agent provider for this project (defaults to 'claude') */
+  provider?: ProviderId;
   /** When true, agents for this project use git worktrees for isolation */
   useWorktrees?: boolean;
 }

v2/src/lib/utils/agent-tree.test.ts

@@ -1,6 +1,6 @@
 import { describe, it, expect } from 'vitest';
 import { buildAgentTree, countTreeNodes, subtreeCost } from './agent-tree';
-import type { AgentMessage, ToolCallContent, ToolResultContent } from '../adapters/sdk-messages';
+import type { AgentMessage, ToolCallContent, ToolResultContent } from '../adapters/claude-messages';
 import type { AgentTreeNode } from './agent-tree';
 
 // Helper to create typed AgentMessages

v2/src/lib/utils/agent-tree.ts

@@ -1,7 +1,7 @@
 // Agent tree builder — constructs hierarchical tree from agent messages
 // Subagents are identified by parent_tool_use_id on their messages
 
-import type { AgentMessage, ToolCallContent, CostContent } from '../adapters/sdk-messages';
+import type { AgentMessage, ToolCallContent, CostContent } from '../adapters/claude-messages';
 
 export interface AgentTreeNode {
   id: string;

v2/src/lib/utils/tool-files.test.ts

@@ -1,6 +1,6 @@
 import { describe, it, expect } from 'vitest';
 import { extractFilePaths, extractWritePaths, extractWorktreePath } from './tool-files';
-import type { ToolCallContent } from '../adapters/sdk-messages';
+import type { ToolCallContent } from '../adapters/claude-messages';
 
 function makeTc(name: string, input: unknown): ToolCallContent {
   return { toolUseId: `tu-${Math.random()}`, name, input };

v2/src/lib/utils/tool-files.ts

@@ -1,7 +1,7 @@
 // Extracts file paths from agent tool_call inputs
 // Used by ContextTab (all file ops) and conflicts store (write ops only)
 
-import type { ToolCallContent } from '../adapters/sdk-messages';
+import type { ToolCallContent } from '../adapters/claude-messages';
 
 export interface ToolFileRef {
   path: string;