feat(obsidian): show trace tiers in file explorer

plugins/obsidian/README.md

@@ -6,10 +6,11 @@ Lineage view and tier visibility for [Noema](https://github.com/Fail-Safe/Noema)
 
 - **Lineage sidebar.** When you open a trace, the sidebar shows its `derived_from` ancestors and the traces derived from it, both clickable. Useful for navigating "where did this come from / what came out of this" without leaving the editor.
 - **Tier badge in the status bar.** Shows `[s]` / `[m]` / `[L]` for the currently-open trace and a tooltip note that long-tier traces are immutable.
+- **Tier badges in the file explorer.** Shows the same tier shorthand beside every trace in the configured traces folder, including while disconnected from the MCP endpoint. Enabled by default and independently toggleable in the plugin settings.
 - **Connection status.** The same status bar item shows whether the plugin is connected to a `noema serve --transport http` endpoint. A keyed-mode server that rejects (or requires) the bearer key shows `noema: unauthorized` instead of `noema: disconnected`, and pops a one-time notice pointing you at the bearer-key setting — so a wrong key reads as a credential problem, not an unreachable server.
 - **Noema-backed trace search.** `Noema: Search traces` calls the connected cortex's `search_traces` MCP tool and opens the selected trace in Obsidian. The plugin setting chooses `hybrid`, `semantic`, or `lexical`; the modal can show 5 or 10 results. Server-side `cortex.md` still owns embedding configuration and `hybrid_weight`.
 
-That's intentionally the whole feature set for v0.3. File-explorer decorations and federation status panels are reasonable next-version additions but aren't here yet.
+That's intentionally the whole feature set for v0.4. Saved search views and federation status panels are reasonable next-version additions but aren't here yet.
 
 ## Setup
 
@@ -31,6 +32,7 @@ That's intentionally the whole feature set for v0.3. File-explorer decorations a
    - **HTTP endpoint** — e.g. `https://noema.local:3000`
    - **Bearer key** — required if the server is in keyed mode (`NOEMA_MCP_KEY` or `access.shared_key_file`); leave empty for open-mode (loopback only).
    - **Test connection** — click to probe the endpoint immediately and get a notice telling you whether it connected, was rejected (HTTP 401, fix the key), or was unreachable.
+   - **Show tier badges in file explorer** — enabled by default; turn it off to hide `[s]`, `[m]`, and `[L]` beside trace filenames.
    - **Noema search mode** — used by `Noema: Search traces`; defaults to `Hybrid`.
 6. Open the lineage sidebar via the command palette: `Noema: Open lineage view`.
 
@@ -60,4 +62,4 @@ Produces `main.js` next to `manifest.json`. For development, `npm run dev` watch
 
 Noema is intentionally lightweight infrastructure — markdown files plus a SQLite index, no opinion about your editor. This plugin matches that spirit: it adds the pieces of UI that genuinely benefit from being inside Obsidian (lineage navigation, tier visibility, trace creation, appends, and Noema-ranked trace search) and stays out of the way for everything else. Editing happens in Obsidian's native editor and file management uses Obsidian's native file explorer.
 
-If you want richer integration (file-explorer decorations, saved search views, federation status panel), file an issue against the main repo with the use case — they're easy to add as separate, opt-in commands.
+If you want richer integration (saved search views or a federation status panel), file an issue against the main repo with the use case — they're easy to add as separate, opt-in commands.

plugins/obsidian/manifest.json

@@ -1,7 +1,7 @@
 {
   "id": "noema",
   "name": "Noema",
-  "version": "0.3.0",
+  "version": "0.4.0",
   "minAppVersion": "1.4.0",
   "description": "Lineage view, tier visibility, and Noema-backed search for Noema cortex traces. Connects to a `noema serve --transport http` endpoint.",
   "author": "Mark Baker (https://github.com/Fail-Safe)",

plugins/obsidian/package.json

@@ -1,6 +1,6 @@
 {
   "name": "noema-obsidian",
-  "version": "0.3.0",
+  "version": "0.4.0",
   "description": "Lineage view, tier visibility, and Noema-backed search for Noema cortex traces inside Obsidian.",
   "main": "main.js",
   "scripts": {

plugins/obsidian/src/file-explorer-tiers.ts

@@ -0,0 +1,150 @@
+import { App, normalizePath, Plugin, TFile } from "obsidian";
+import { readTraceMetadata, tierGlyph, tierLabel } from "./tier-status";
+
+const FILE_EXPLORER_VIEW_TYPE = "file-explorer";
+const FILE_ROW_SELECTOR = ".nav-file-title[data-path]";
+const BADGE_CLASS = "noema-file-tier-badge";
+
+// FileExplorerTierBadges adds tier visibility to Obsidian's native file
+// explorer without taking ownership of its tree. Obsidian does not expose a
+// public row-render hook, so the DOM selectors are deliberately isolated in
+// this class. Metadata and lifecycle updates still use supported APIs.
+export class FileExplorerTierBadges {
+	private readonly observers = new Map<HTMLElement, MutationObserver>();
+	private active = false;
+	private refreshFrame: number | null = null;
+
+	constructor(
+		private readonly app: App,
+		private readonly plugin: Plugin,
+		private readonly getTracesFolder: () => string,
+		private readonly getEnabled: () => boolean
+	) {}
+
+	start(): void {
+		this.active = true;
+		this.app.workspace.onLayoutReady(() => {
+			if (!this.active) return;
+			this.bindExplorerViews();
+
+			this.plugin.registerEvent(
+				this.app.workspace.on("layout-change", () => this.bindExplorerViews())
+			);
+			this.plugin.registerEvent(
+				this.app.metadataCache.on("changed", (file) => this.refreshFile(file.path))
+			);
+			this.plugin.registerEvent(this.app.vault.on("create", () => this.refresh()));
+			this.plugin.registerEvent(this.app.vault.on("rename", () => this.refresh()));
+			this.plugin.registerEvent(this.app.vault.on("delete", () => this.refresh()));
+		});
+	}
+
+	stop(): void {
+		this.active = false;
+		if (this.refreshFrame !== null) {
+			window.cancelAnimationFrame(this.refreshFrame);
+			this.refreshFrame = null;
+		}
+		for (const [root, observer] of this.observers) {
+			observer.disconnect();
+			this.removeBadges(root);
+		}
+		this.observers.clear();
+	}
+
+	refresh(): void {
+		if (!this.active || this.refreshFrame !== null) return;
+		this.refreshFrame = window.requestAnimationFrame(() => {
+			this.refreshFrame = null;
+			for (const root of this.observers.keys()) {
+				root
+					.querySelectorAll<HTMLElement>(FILE_ROW_SELECTOR)
+					.forEach((row) => this.decorateRow(row));
+			}
+		});
+	}
+
+	private bindExplorerViews(): void {
+		const currentRoots = new Set(
+			this.app.workspace
+				.getLeavesOfType(FILE_EXPLORER_VIEW_TYPE)
+				.map((leaf) => leaf.view.containerEl)
+		);
+
+		for (const [root, observer] of this.observers) {
+			if (currentRoots.has(root)) continue;
+			observer.disconnect();
+			this.removeBadges(root);
+			this.observers.delete(root);
+		}
+
+		for (const root of currentRoots) {
+			if (this.observers.has(root)) continue;
+			const observer = new MutationObserver(() => this.refresh());
+			observer.observe(root, { childList: true, subtree: true });
+			this.observers.set(root, observer);
+		}
+
+		this.refresh();
+	}
+
+	private refreshFile(path: string): void {
+		if (!this.active) return;
+		for (const root of this.observers.keys()) {
+			root.querySelectorAll<HTMLElement>(FILE_ROW_SELECTOR).forEach((row) => {
+				if (row.dataset.path === path) this.decorateRow(row);
+			});
+		}
+	}
+
+	private decorateRow(row: HTMLElement): void {
+		if (!this.getEnabled()) {
+			this.removeBadge(row);
+			return;
+		}
+
+		const path = row.dataset.path;
+		const folder = normalizePath(this.getTracesFolder().trim() || "traces").replace(/\/$/, "");
+		if (!path || !path.startsWith(`${folder}/`)) {
+			this.removeBadge(row);
+			return;
+		}
+
+		const file = this.app.vault.getAbstractFileByPath(path);
+		if (!(file instanceof TFile) || file.extension !== "md") {
+			this.removeBadge(row);
+			return;
+		}
+
+		const metadata = readTraceMetadata(this.app, file);
+		if (!metadata?.id) {
+			this.removeBadge(row);
+			return;
+		}
+
+		let badge = row.querySelector<HTMLElement>(`.${BADGE_CLASS}`);
+		if (!badge) {
+			badge = document.createElement("span");
+			badge.classList.add(BADGE_CLASS);
+			const title = row.querySelector<HTMLElement>(".nav-file-title-content");
+			if (title) title.before(badge);
+			else row.prepend(badge);
+		}
+
+		const glyph = `[${tierGlyph(metadata.tier)}]`;
+		const label = tierLabel(metadata.tier);
+		badge.className = `${BADGE_CLASS} noema-file-tier-${metadata.tier}`;
+		if (badge.textContent !== glyph) badge.textContent = glyph;
+		badge.dataset.tier = metadata.tier;
+		badge.setAttribute("title", label);
+		badge.setAttribute("aria-label", label);
+	}
+
+	private removeBadge(row: HTMLElement): void {
+		row.querySelector(`.${BADGE_CLASS}`)?.remove();
+	}
+
+	private removeBadges(root: HTMLElement): void {
+		root.querySelectorAll(`.${BADGE_CLASS}`).forEach((badge) => badge.remove());
+	}
+}

plugins/obsidian/src/main.ts

@@ -7,6 +7,7 @@ import { CreateTraceModal } from "./create-modal";
 import { ImmutableWarning } from "./immutable-warning";
 import { openAppendModalFromActive } from "./append-modal";
 import { SearchModal } from "./search-modal";
+import { FileExplorerTierBadges } from "./file-explorer-tiers";
 
 const STATUS_PING_INTERVAL_MS = 30_000;
 
@@ -44,6 +45,7 @@ export default class NoemaPlugin extends Plugin {
 	// unreachable server (actionable: check the endpoint/network).
 	private connState: ConnState = "disconnected";
 	private immutableWarning: ImmutableWarning | null = null;
+	private fileExplorerTierBadges: FileExplorerTierBadges | null = null;
 
 	async onload(): Promise<void> {
 		await this.loadSettings();
@@ -119,6 +121,13 @@ export default class NoemaPlugin extends Plugin {
 		});
 
 		this.immutableWarning = new ImmutableWarning(this.app, this);
+		this.fileExplorerTierBadges = new FileExplorerTierBadges(
+			this.app,
+			this,
+			() => this.settings.tracesFolder,
+			() => this.settings.showFileExplorerTierBadges
+		);
+		this.fileExplorerTierBadges.start();
 
 		// Re-render the status bar AND immutable-warning banner when
 		// the active file changes (tier glyph follows the user) or
@@ -159,6 +168,7 @@ export default class NoemaPlugin extends Plugin {
 		// Clean up any lingering banner DOM so a plugin reload during
 		// active development doesn't leave orphan elements behind.
 		this.immutableWarning?.removeAll();
+		this.fileExplorerTierBadges?.stop();
 	}
 
 	async loadSettings(): Promise<void> {
@@ -170,6 +180,10 @@ export default class NoemaPlugin extends Plugin {
 		await this.saveData(this.settings);
 	}
 
+	refreshFileExplorerTierBadges(): void {
+		this.fileExplorerTierBadges?.refresh();
+	}
+
 	// refreshClient is called from the settings tab when the
 	// endpoint or bearer key changes. We keep a single McpClient
 	// instance so the JSON-RPC id counter stays monotonic across

plugins/obsidian/src/mcp-client.ts

@@ -343,7 +343,7 @@ export class McpClient {
 			params: {
 				protocolVersion: MCP_PROTOCOL_VERSION,
 				capabilities: {},
-				clientInfo: { name: "noema-obsidian", version: "0.3.0" },
+				clientInfo: { name: "noema-obsidian", version: "0.4.0" },
 			},
 		};
 		const resp = await mcpFetch(

plugins/obsidian/src/settings.ts

@@ -5,6 +5,7 @@ export interface NoemaSettings {
 	endpoint: string;
 	bearerKey: string;
 	tracesFolder: string;
+	showFileExplorerTierBadges: boolean;
 	defaultAuthor: string;
 	searchMode: "lexical" | "semantic" | "hybrid";
 }
@@ -13,14 +14,16 @@ export interface NoemaSettings {
 // the plugin starts in "disconnected" state on a fresh install rather
 // than blindly trying to reach a localhost URL. tracesFolder defaults
 // to "traces" because that's the cortex layout convention; users with
-// a non-standard layout (rare) can override. defaultAuthor is empty
-// by default — the create-trace flow omits the author field entirely
-// when the setting is empty, letting the cortex's own author logic
-// decide what to record.
+// a non-standard layout (rare) can override. File explorer badges are
+// visible by default and can be hidden as an Obsidian display preference.
+// defaultAuthor is empty by default — the create-trace flow omits the
+// author field entirely when the setting is empty, letting the cortex's
+// own author logic decide what to record.
 export const DEFAULT_SETTINGS: NoemaSettings = {
 	endpoint: "",
 	bearerKey: "",
 	tracesFolder: "traces",
+	showFileExplorerTierBadges: true,
 	defaultAuthor: "",
 	searchMode: "hybrid",
 };
@@ -100,6 +103,20 @@ export class NoemaSettingTab extends PluginSettingTab {
 					.onChange(async (value) => {
 						this.plugin.settings.tracesFolder = value.trim() || "traces";
 						await this.plugin.saveSettings();
+						this.plugin.refreshFileExplorerTierBadges();
+					})
+			);
+
+		new Setting(containerEl)
+			.setName("Show tier badges in file explorer")
+			.setDesc("Show [s], [m], and [L] beside traces in the configured traces folder.")
+			.addToggle((toggle) =>
+				toggle
+					.setValue(this.plugin.settings.showFileExplorerTierBadges)
+					.onChange(async (value) => {
+						this.plugin.settings.showFileExplorerTierBadges = value;
+						await this.plugin.saveSettings();
+						this.plugin.refreshFileExplorerTierBadges();
 					})
 			);
 

plugins/obsidian/styles.css

@@ -15,6 +15,33 @@
 	margin-right: 4px;
 }
 
+/* ---- File explorer tier badges ---- */
+
+.noema-file-tier-badge {
+	display: inline-block;
+	flex: 0 0 auto;
+	min-width: 2.25em;
+	margin-inline-end: 4px;
+	font-family: var(--font-monospace);
+	font-size: var(--font-ui-smaller);
+	font-weight: 600;
+	line-height: var(--line-height-tight, 1.2);
+	text-align: center;
+	color: var(--text-faint);
+}
+
+.noema-file-tier-mid {
+	color: var(--text-muted);
+}
+
+.noema-file-tier-long {
+	color: var(--text-warning, var(--text-accent));
+}
+
+.noema-file-tier-unknown {
+	color: var(--text-error, var(--text-muted));
+}
+
 .noema-status-ok {
 	color: var(--text-success, var(--text-normal));
 }