fix(coding-agent): route compaction through streamFn

closes #4484

packages/coding-agent/src/core/agent-session.ts

@@ -31,6 +31,7 @@ import {
 	isContextOverflow,
 	modelsAreEqual,
 	resetApiProviders,
+	streamSimple,
 } from "@earendil-works/pi-ai";
 import { theme } from "../modes/interactive/theme/theme.js";
 import { stripFrontmatter } from "../utils/frontmatter.js";
@@ -367,6 +368,18 @@ export class AgentSession {
 		throw new Error(formatNoApiKeyFoundMessage(model.provider));
 	}
 
+	private async _getCompactionRequestAuth(model: Model<any>): Promise<{
+		apiKey?: string;
+		headers?: Record<string, string>;
+	}> {
+		if (this.agent.streamFn === streamSimple) {
+			return this._getRequiredRequestAuth(model);
+		}
+
+		const result = await this._modelRegistry.getApiKeyAndHeaders(model);
+		return result.ok ? { apiKey: result.apiKey, headers: result.headers } : {};
+	}
+
 	/**
 	 * Install tool hooks once on the Agent instance.
 	 *
@@ -1618,7 +1631,7 @@ export class AgentSession {
 				throw new Error(formatNoModelSelectedMessage());
 			}
 
-			const { apiKey, headers } = await this._getRequiredRequestAuth(this.model);
+			const { apiKey, headers } = await this._getCompactionRequestAuth(this.model);
 
 			const pathEntries = this.sessionManager.getBranch();
 			const settings = this.settingsManager.getCompactionSettings();
@@ -1676,6 +1689,7 @@ export class AgentSession {
 					customInstructions,
 					this._compactionAbortController.signal,
 					this.thinkingLevel,
+					this.agent.streamFn,
 				);
 				summary = result.summary;
 				firstKeptEntryId = result.firstKeptEntryId;
@@ -1864,18 +1878,25 @@ export class AgentSession {
 				return;
 			}
 
-			const authResult = await this._modelRegistry.getApiKeyAndHeaders(this.model);
-			if (!authResult.ok || !authResult.apiKey) {
-				this._emit({
-					type: "compaction_end",
-					reason,
-					result: undefined,
-					aborted: false,
-					willRetry: false,
-				});
-				return;
+			let apiKey: string | undefined;
+			let headers: Record<string, string> | undefined;
+			if (this.agent.streamFn === streamSimple) {
+				const authResult = await this._modelRegistry.getApiKeyAndHeaders(this.model);
+				if (!authResult.ok || !authResult.apiKey) {
+					this._emit({
+						type: "compaction_end",
+						reason,
+						result: undefined,
+						aborted: false,
+						willRetry: false,
+					});
+					return;
+				}
+				apiKey = authResult.apiKey;
+				headers = authResult.headers;
+			} else {
+				({ apiKey, headers } = await this._getCompactionRequestAuth(this.model));
 			}
-			const { apiKey, headers } = authResult;
 
 			const pathEntries = this.sessionManager.getBranch();
 
@@ -1941,6 +1962,7 @@ export class AgentSession {
 					undefined,
 					this._autoCompactionAbortController.signal,
 					this.thinkingLevel,
+					this.agent.streamFn,
 				);
 				summary = compactResult.summary;
 				firstKeptEntryId = compactResult.firstKeptEntryId;