fix(pi): refresh-primers used a nonexistent Pi session API; share one resolver

The Pi primer raw provider probed SessionManager.listSessions +
loadEntriesFromFile, neither of which exists in pi-coding-agent's public API
(listing is SessionManager.listAll; entries come from readFileSync +
parseSessionEntries). The identical drift was fixed for the retrospective
provider in #201 but this second copy kept the dead lookup: the factory
converts the throw into a null provider, so scheduled refresh-primers silently
ran closed-book on Pi, and dream-run telemetry recorded 'Pi session APIs
unavailable' for runs on hosts whose long-running Pi process predated #201.

Extract the API lookup into one shared resolver (pi-session-api.ts) consumed by
both providers, so a future pi-coding-agent drift breaks exactly one place. Add
default-path tests against the actually installed package — the providers'
dependency-injected unit tests could never catch a broken default lookup, which
is exactly how this survived #201.

Author: ualtinok

packages/pi-plugin/src/dreamer/pi-session-api.test.ts

@@ -0,0 +1,46 @@
+/// <reference types="bun-types" />
+
+import { describe, expect, it } from "bun:test";
+import { loadDefaultPiSessionApi } from "./pi-session-api";
+
+/**
+ * These tests exercise the DEFAULT resolution path against the actually
+ * installed pi-coding-agent package. The Pi session-listing API drifted once
+ * (`SessionManager.listSessions` never existed publicly) and the providers'
+ * dependency-injected unit tests could not catch it — every test supplied its
+ * own listSessions stub, so the broken default lookup only failed at runtime
+ * inside the dreamer. This is the missing coverage: if pi-coding-agent renames
+ * or removes the session APIs again, this fails in CI instead of silently
+ * degrading retrospective/refresh-primers.
+ */
+describe("loadDefaultPiSessionApi", () => {
+	it("resolves the session APIs from the installed pi-coding-agent", async () => {
+		const api = await loadDefaultPiSessionApi();
+		expect(typeof api.listSessions).toBe("function");
+		expect(typeof api.loadEntriesFromFile).toBe("function");
+	});
+
+	it("parses JSONL session entries through the resolved loader", async () => {
+		const api = await loadDefaultPiSessionApi();
+		const { mkdtempSync, writeFileSync } = await import("node:fs");
+		const { tmpdir } = await import("node:os");
+		const { join } = await import("node:path");
+
+		const dir = mkdtempSync(join(tmpdir(), "pi-session-api-test-"));
+		const file = join(dir, "session.jsonl");
+		const entry = {
+			type: "message",
+			id: "e1",
+			message: {
+				role: "user",
+				timestamp: 123,
+				content: [{ type: "text", text: "hello" }],
+			},
+		};
+		writeFileSync(file, `${JSON.stringify(entry)}\n`);
+
+		const entries = await api.loadEntriesFromFile(file);
+		expect(Array.isArray(entries)).toBe(true);
+		expect(entries.length).toBeGreaterThan(0);
+	});
+});

packages/pi-plugin/src/dreamer/pi-session-api.ts

@@ -0,0 +1,48 @@
+import { readFileSync } from "node:fs";
+
+/**
+ * Shared resolver for pi-coding-agent's session APIs, used by every Pi dreamer
+ * provider that reads historical JSONL sessions (retrospective, refresh-primers).
+ *
+ * ONE resolver on purpose: the session-listing API drifted once already
+ * (`SessionManager.listSessions` never existed publicly; listing is
+ * `SessionManager.listAll`, and `loadEntriesFromFile` is not exported — entries
+ * come from `readFileSync` + `parseSessionEntries`). When each provider carried
+ * its own copy of this lookup, one copy got fixed and the other kept probing the
+ * nonexistent API, so its feature silently degraded. Any future Pi API drift
+ * should break exactly one resolver and one test.
+ */
+export interface PiSessionApi {
+	listSessions: (sessionDir?: string) => unknown[] | Promise<unknown[]>;
+	loadEntriesFromFile: (filePath: string) => unknown[] | Promise<unknown[]>;
+}
+
+const PI_CODING_AGENT_MODULE = "@earendil-works/pi-coding-agent";
+
+export async function loadDefaultPiSessionApi(): Promise<PiSessionApi> {
+	const mod = (await import(/* @vite-ignore */ PI_CODING_AGENT_MODULE)) as {
+		SessionManager?: {
+			listAll?: (sessionDir?: string) => unknown[] | Promise<unknown[]>;
+		};
+		loadEntriesFromFile?: (filePath: string) => unknown[] | Promise<unknown[]>;
+		parseSessionEntries?: (content: string) => unknown[];
+	};
+	const listSessions = mod.SessionManager?.listAll;
+	if (typeof listSessions !== "function") {
+		throw new Error(
+			"Pi session APIs unavailable: expected SessionManager.listAll on pi-coding-agent",
+		);
+	}
+	// loadEntriesFromFile is NOT part of pi-coding-agent's public API — fall back
+	// to readFileSync + parseSessionEntries (both exported).
+	const loadEntriesFromFile: PiSessionApi["loadEntriesFromFile"] =
+		mod.loadEntriesFromFile ??
+		((filePath: string) => {
+			const content = readFileSync(filePath, "utf8");
+			return mod.parseSessionEntries?.(content) ?? [];
+		});
+	return {
+		listSessions: listSessions.bind(mod.SessionManager),
+		loadEntriesFromFile,
+	};
+}

packages/pi-plugin/src/dreamer/primer-raw-provider-pi.ts

@@ -1,6 +1,7 @@
 import type { RawMessageProvider } from "@magic-context/core/hooks/magic-context/read-session-chunk";
 import type { RawMessage } from "@magic-context/core/hooks/magic-context/read-session-raw";
 import { convertEntriesToRawMessages } from "../read-session-pi";
+import { loadDefaultPiSessionApi } from "./pi-session-api";
 
 /**
  * Pi `primerRawProviderFactory`: resolve a historical session id to a
@@ -18,8 +19,6 @@ export interface PiPrimerRawProviderDeps {
 	sessionDir?: string;
 }
 
-const PI_CODING_AGENT_MODULE = "@earendil-works/pi-coding-agent";
-
 interface PiSessionInfoLike {
 	id?: unknown;
 	path?: unknown;
@@ -41,7 +40,7 @@ export function createPiPrimerRawProviderFactory(
 				loadEntriesFromFile: deps.loadEntriesFromFile,
 			};
 		}
-		resolved ??= loadDefaultPiSessionDeps();
+		resolved ??= loadDefaultPiSessionApi();
 		return resolved;
 	};
 
@@ -75,30 +74,3 @@ export function createPiPrimerRawProviderFactory(
 		}
 	};
 }
-
-async function loadDefaultPiSessionDeps(): Promise<
-	Required<
-		Pick<PiPrimerRawProviderDeps, "listSessions" | "loadEntriesFromFile">
-	>
-> {
-	const mod = (await import(/* @vite-ignore */ PI_CODING_AGENT_MODULE)) as {
-		SessionManager?: {
-			listSessions?: (sessionDir?: string) => unknown[] | Promise<unknown[]>;
-		};
-		loadEntriesFromFile?: (filePath: string) => unknown[] | Promise<unknown[]>;
-	};
-	const listSessions = mod.SessionManager?.listSessions;
-	const loadEntriesFromFile = mod.loadEntriesFromFile;
-	if (
-		typeof listSessions !== "function" ||
-		typeof loadEntriesFromFile !== "function"
-	) {
-		throw new Error(
-			"Pi session APIs unavailable: expected SessionManager.listSessions and loadEntriesFromFile",
-		);
-	}
-	return {
-		listSessions: listSessions.bind(mod.SessionManager),
-		loadEntriesFromFile,
-	};
-}

packages/pi-plugin/src/dreamer/retrospective-raw-provider-pi.ts

@@ -1,4 +1,3 @@
-import { readFileSync } from "node:fs";
 import { resolve } from "node:path";
 
 import type {
@@ -7,6 +6,7 @@ import type {
 	RetrospectiveRawProvider,
 	RetrospectiveSinceRead,
 } from "@magic-context/core/features/magic-context/dreamer/retrospective-raw-provider";
+import { loadDefaultPiSessionApi } from "./pi-session-api";
 
 interface PiSessionInfoLike {
 	id?: unknown;
@@ -34,8 +34,6 @@ export interface PiRetrospectiveRawProviderDeps {
 	loadEntriesFromFile?: (filePath: string) => unknown[] | Promise<unknown[]>;
 }
 
-const PI_CODING_AGENT_MODULE = "@earendil-works/pi-coding-agent";
-
 export class PiRetrospectiveRawProvider implements RetrospectiveRawProvider {
 	private readonly sessionPathById = new Map<string, string>();
 	private resolvedDefaultDeps: Promise<
@@ -144,7 +142,7 @@ export class PiRetrospectiveRawProvider implements RetrospectiveRawProvider {
 				loadEntriesFromFile: this.deps.loadEntriesFromFile,
 			};
 		}
-		this.resolvedDefaultDeps ??= loadDefaultPiSessionDeps();
+		this.resolvedDefaultDeps ??= loadDefaultPiSessionApi();
 		return this.resolvedDefaultDeps;
 	}
 }
@@ -184,37 +182,3 @@ function extractPiTextContent(content: unknown): string {
 		})
 		.join("\n");
 }
-
-async function loadDefaultPiSessionDeps(): Promise<
-	Required<
-		Pick<PiRetrospectiveRawProviderDeps, "listSessions" | "loadEntriesFromFile">
-	>
-> {
-	const mod = (await import(/* @vite-ignore */ PI_CODING_AGENT_MODULE)) as {
-		SessionManager?: {
-			listAll?: (sessionDir?: string) => unknown[] | Promise<unknown[]>;
-		};
-		loadEntriesFromFile?: (filePath: string) => unknown[] | Promise<unknown[]>;
-		parseSessionEntries?: (content: string) => unknown[];
-	};
-	const listSessions = mod.SessionManager?.listAll;
-	if (typeof listSessions !== "function") {
-		throw new Error(
-			"Pi session APIs unavailable: expected SessionManager.listAll on pi-coding-agent",
-		);
-	}
-	// loadEntriesFromFile is NOT part of pi-coding-agent's public API —
-	// fall back to readFileSync + parseSessionEntries (both exported).
-	const loadEntriesFromFile: (
-		filePath: string,
-	) => unknown[] | Promise<unknown[]> =
-		mod.loadEntriesFromFile ??
-		((filePath: string) => {
-			const content = readFileSync(filePath, "utf8");
-			return mod.parseSessionEntries?.(content) ?? [];
-		});
-	return {
-		listSessions: listSessions.bind(mod.SessionManager),
-		loadEntriesFromFile,
-	};
-}