get_active_note tool

Returns the path + content of the currently focused note, or null
fields when no note is active. Read-only; mobile-safe.

Closes #48.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/agent/tools/vault/__tests__/get_active_note.test.ts

@@ -0,0 +1,29 @@
+import { describe, expect, it, vi } from "vitest";
+import { App, TFile } from "obsidian";
+
+import { getActiveNoteTool } from "@/agent/tools/vault/get_active_note";
+import type CoIntelligencePlugin from "@/CoIntelligencePlugin";
+import type { ToolExecutionContext } from "@/agent/types";
+
+function makeCtx(app: App): ToolExecutionContext {
+    return { app, plugin: {} as CoIntelligencePlugin, toolCallId: "c" };
+}
+
+describe("getActiveNoteTool", () => {
+    it("returns nulls when no active file", async () => {
+        const app = new App();
+        app.workspace.getActiveFile = vi.fn().mockReturnValue(null);
+        const out = await getActiveNoteTool.execute({}, makeCtx(app));
+        expect(out).toEqual({ path: null, content: null });
+    });
+
+    it("returns path + content for an active file", async () => {
+        const file = new TFile();
+        file.path = "Active.md";
+        const app = new App();
+        app.workspace.getActiveFile = vi.fn().mockReturnValue(file);
+        app.vault.cachedRead = vi.fn().mockResolvedValue("body");
+        const out = await getActiveNoteTool.execute({}, makeCtx(app));
+        expect(out).toEqual({ path: "Active.md", content: "body" });
+    });
+});

src/agent/tools/vault/get_active_note.ts

@@ -0,0 +1,35 @@
+import { z } from "zod";
+
+import type { CoiTool } from "@/agent/types";
+
+const inputSchema = z.object({});
+
+type Input = z.infer<typeof inputSchema>;
+
+interface Output {
+    path: string | null;
+    content: string | null;
+}
+
+/**
+ * `get_active_note` — returns the path and content of the note the user has
+ * focused in Obsidian. Returns nulls when no note is active (e.g. a non-file
+ * pane is focused). Read-only; no approval.
+ */
+export const getActiveNoteTool: CoiTool<Input, Output> = {
+    name: "get_active_note",
+    description:
+        "Get the path and content of the note the user is currently viewing in Obsidian, or nulls if no note is active.",
+    inputSchema,
+    requiresApproval: false,
+    scope: "vault",
+    platforms: ["desktop", "mobile"],
+    async execute(_input, { app }) {
+        const file = app.workspace.getActiveFile();
+        if (!file) {
+            return { path: null, content: null };
+        }
+        const content = await app.vault.cachedRead(file);
+        return { path: file.path, content };
+    },
+};