feat(coding-agent): accept native extension providers

Allow extensions to register complete pi-ai Provider objects while preserving models.json composition and resolved provider auth access.

Refs #4823 and #4824.

packages/coding-agent/src/core/extensions/loader.ts

@@ -8,6 +8,7 @@ import { createRequire } from "node:module";
 import * as path from "node:path";
 import { fileURLToPath } from "node:url";
 import * as _bundledPiAgentCore from "@earendil-works/pi-agent-core";
+import type { Provider } from "@earendil-works/pi-ai";
 import * as _bundledPiAiCompat from "@earendil-works/pi-ai/compat";
 import * as _bundledPiAiOauth from "@earendil-works/pi-ai/oauth";
 import * as _bundledPiAiProviders from "@earendil-works/pi-ai/providers/all";
@@ -195,6 +196,7 @@ export function createExtensionRuntime(): ExtensionRuntime {
 		setThinkingLevel: notInitialized,
 		flagValues: new Map(),
 		pendingProviderRegistrations: [],
+		pendingNativeProviderRegistrations: [],
 		assertActive,
 		invalidate: (message) => {
 			state.staleMessage ??=
@@ -206,8 +208,14 @@ export function createExtensionRuntime(): ExtensionRuntime {
 		registerProvider: (name, config, extensionPath = "<unknown>") => {
 			runtime.pendingProviderRegistrations.push({ name, config, extensionPath });
 		},
+		registerNativeProvider: (provider, extensionPath = "<unknown>") => {
+			runtime.pendingNativeProviderRegistrations.push({ provider, extensionPath });
+		},
 		unregisterProvider: (name) => {
 			runtime.pendingProviderRegistrations = runtime.pendingProviderRegistrations.filter((r) => r.name !== name);
+			runtime.pendingNativeProviderRegistrations = runtime.pendingNativeProviderRegistrations.filter(
+				(r) => r.provider.id !== name,
+			);
 		},
 	};
 
@@ -363,9 +371,14 @@ function createExtensionAPI(
 			runtime.setThinkingLevel(level);
 		},
 
-		registerProvider(name: string, config: ProviderConfig) {
+		registerProvider(providerOrName: Provider | string, config?: ProviderConfig) {
 			runtime.assertActive();
-			runtime.registerProvider(name, config, extension.path);
+			if (typeof providerOrName === "string") {
+				if (!config) throw new Error("Provider config is required when registering by name");
+				runtime.registerProvider(providerOrName, config, extension.path);
+				return;
+			}
+			runtime.registerNativeProvider(providerOrName, extension.path);
 		},
 
 		unregisterProvider(name: string) {

packages/coding-agent/src/core/extensions/runner.ts

@@ -3,7 +3,7 @@
  */
 
 import type { AgentMessage } from "@earendil-works/pi-agent-core";
-import type { ImageContent, Model, ProviderHeaders } from "@earendil-works/pi-ai";
+import type { ImageContent, Model, Provider, ProviderHeaders } from "@earendil-works/pi-ai";
 import type { KeyId } from "@earendil-works/pi-tui";
 import { type Theme, theme } from "../../modes/interactive/theme/theme.ts";
 import type { ResourceDiagnostic } from "../diagnostics.ts";
@@ -313,6 +313,7 @@ export class ExtensionRunner {
 		contextActions: ExtensionContextActions,
 		providerActions?: {
 			registerProvider?: (name: string, config: ProviderConfig) => void;
+			registerNativeProvider?: (provider: Provider) => void;
 			unregisterProvider?: (name: string) => void;
 		},
 	): void {
@@ -363,6 +364,23 @@ export class ExtensionRunner {
 			}
 		}
 		this.runtime.pendingProviderRegistrations = [];
+		for (const { provider, extensionPath } of this.runtime.pendingNativeProviderRegistrations) {
+			try {
+				if (providerActions?.registerNativeProvider) {
+					providerActions.registerNativeProvider(provider);
+				} else {
+					this.modelRegistry.registerProvider(provider);
+				}
+			} catch (err) {
+				this.emitError({
+					extensionPath,
+					event: "register_provider",
+					error: err instanceof Error ? err.message : String(err),
+					stack: err instanceof Error ? err.stack : undefined,
+				});
+			}
+		}
+		this.runtime.pendingNativeProviderRegistrations = [];
 
 		// From this point on, provider registration/unregistration takes effect immediately
 		// without requiring a /reload.
@@ -373,6 +391,13 @@ export class ExtensionRunner {
 			}
 			this.modelRegistry.registerProvider(name, config);
 		};
+		this.runtime.registerNativeProvider = (provider) => {
+			if (providerActions?.registerNativeProvider) {
+				providerActions.registerNativeProvider(provider);
+				return;
+			}
+			this.modelRegistry.registerProvider(provider);
+		};
 		this.runtime.unregisterProvider = (name) => {
 			if (providerActions?.unregisterProvider) {
 				providerActions.unregisterProvider(name);

packages/coding-agent/src/core/extensions/types.ts

@@ -24,6 +24,7 @@ import type {
 	Model,
 	OAuthCredentials,
 	OAuthLoginCallbacks,
+	Provider,
 	ProviderHeaders,
 	RefreshModelsContext,
 	SimpleStreamOptions,
@@ -1378,6 +1379,7 @@ export interface ExtensionAPI {
 	 *   }
 	 * });
 	 */
+	registerProvider(provider: Provider): void;
 	registerProvider(name: string, config: ProviderConfig): void;
 
 	/**
@@ -1553,8 +1555,10 @@ export type SetLabelHandler = (entryId: string, label: string | undefined) => vo
  */
 export interface ExtensionRuntimeState {
 	flagValues: Map<string, boolean | string>;
-	/** Provider registrations queued during extension loading, processed when runner binds */
+	/** Legacy provider-config registrations queued during extension loading, processed when runner binds. */
 	pendingProviderRegistrations: Array<{ name: string; config: ProviderConfig; extensionPath: string }>;
+	/** Native pi-ai provider registrations queued during extension loading, processed when runner binds. */
+	pendingNativeProviderRegistrations: Array<{ provider: Provider; extensionPath: string }>;
 	/** Throws when this extension instance is stale after runtime replacement. */
 	assertActive: () => void;
 	/** Marks this extension instance as stale after runtime replacement or reload. */
@@ -1566,6 +1570,7 @@ export interface ExtensionRuntimeState {
 	 * After bindCore(): calls ModelRegistry directly for immediate effect.
 	 */
 	registerProvider: (name: string, config: ProviderConfig, extensionPath?: string) => void;
+	registerNativeProvider: (provider: Provider, extensionPath?: string) => void;
 	unregisterProvider: (name: string, extensionPath?: string) => void;
 }