Link hover web-title preview (hover a chat link → see the page title)

What it is

When an agent's message contains a normal web link (an http:// or https:// URL), hovering the link shows a small tooltip with that web page's actual title — the headline of the article, the name of the repo, the title of the video — instead of just the bare URL. So a link rendered as [read this](https://example.com/some/long/article-slug) reveals "Example — The Real Article Headline" on hover, and you know what you're about to open before you click.

The title is fetched the moment your pointer settles on the link (a brief dwell, not the instant you sweep past it), and remembered, so each link is looked up at most once. While the title is still loading, the tooltip shows the link's domain (e.g. example.com) so it's never blank. If the page can't be reached or has no title, the tooltip just shows the domain — no error, no noise.

This is a desktop feature. On a phone or tablet there is no "hover", so the preview never appears and Omniscio makes no web requests for it on mobile.

The separate "Open with Ctrl+Shift+Q" keyboard hint still appears — but only on the first link of a reply, because that shortcut opens the first link. Every link shows its web title; only the first one also shows the shortcut hint.

Where to find it

Anywhere Omniscio renders an agent's message containing an http:// or https:// link — hover the link and a tooltip appears. It is a desktop feature: a phone or tablet has no hover, so the preview does not appear there.

How it behaves

How to use it

1. Open a chat session where the agent's reply contains a web link.
2. Move your mouse onto the link and pause (about a fifth of a second).
3. A tooltip appears: first the domain, then — a moment later — the page's real title once Omniscio has fetched it.
4. Move off and back on, or hover a different link, and each is fetched once and cached; re-hovering is instant.

Keyboard users: focusing a link with Tab arms the same preview immediately (no dwell needed).

What gets a preview (and what doesn't)

• External web links (http:// / https://) → web-title preview. ✅
• In-app links — file paths the agent wrote (src/main/index.ts), attachments you dropped, omniscio:// deep links, saved-prompt links — these are NOT web pages, so they get no web-title preview (they keep their existing click behavior: opening a file, jumping to a session, etc.). ✅ (see media-link-open.md)

Why the fetch happens "behind the app" (and is safe)

The renderer (the UI) is deliberately not allowed to reach out to the internet on its own — only Omniscio's trusted main process does that. So when you hover a link, the UI asks the main process "what's the title of this page?", and the main process does the fetch. That matters because the link text comes from chat content, which Omniscio treats as untrusted. Every fetch is run through Omniscio's shared network-safety guard, which:

• only allows http/https (no file:, ftp:, etc.);
• refuses links that point at your own machine or private network (localhost, 192.168.x, the cloud-metadata address, and even a public-looking hostname that secretly resolves to a private address) — a standard defense against malicious links;
• gives up after 8 seconds and reads only the first ~100 KB of the page (the title lives at the very top), so a giant or slow page can't bog things down;
• reads only the page's title — nothing else is stored or sent anywhere.

The fetched title is shown as plain text, so a web page can't use its title to inject anything into Omniscio.

Limitations and v1 notes

• Desktop only. No hover on touch devices, so no preview and no fetch on mobile.
• Best-effort title. Pages behind a login, pages that render the title in JavaScript only, or pages that block the fetch show just the domain.
• og:title preferred. Omniscio uses the social-share title (og:title) when present, otherwise the browser-tab <title>.
• No content beyond the title. This is a title preview, not a full link-preview card (no description, no thumbnail).

For agents

How it works

Three layers:

1. Renderer — CopyableLink in agent-markdown-helpers.tsx computes canFetchTitle = isExternalWebLink && supportsHover(). On pointer dwell (LINK_TITLE_DWELL_MS) or focus it arms useLinkTitlePreview, which calls IPC.LINK_PREVIEW_FETCH_TITLE and caches the result per-URL. The title renders as plain text inside the shared <Tooltip>; the hostname stands in until it resolves.
2. IPC — the link-preview domain (channel ipc-channels/link-preview.ts, Zod ipc-schemas/link-preview.ts, handler link-preview-handlers.ts), mirroring the screenshot domain.
3. Main — link-title-fetcher.ts: fetchLinkTitle(url) fetches through the SSRF-hardened redirectAwareFetch (per-hop private-IP + DNS-rebinding checks), with an 8 s deadline + a ≤100 KB streamed read cap, extracts og:title then <title>, cleans it (decoding HTML entities to a bounded fixed point, so a double-encoded title such as Vimeo's ' renders as a real apostrophe), caches it (positive 6 h / negative 5 min), and returns { title } — never throwing, so any failure shows the hostname instead.

The title extractor scans each <meta> tag in isolation so it stays linear-time (a single hovered link to a hostile page can never freeze the main thread). The invariants — SSRF reuse, ReDoS-safety, desktop-only, dwell-gating, caching, plain-text rendering, first-link-only hint — are locked by tests and documented in .claude/memory/contracts/link-title-preview-contract.md.

Related

Related pages

• media-link-open.md — clicking file/media links the agent wrote (opens in your OS default app); explicitly NOT about http(s) URLs.
• deep-links.md — omniscio:// in-app deep links.