[alexandre-vl]

Buttons that show only a glyph, starting with the comment "+" beside a Markdown table header, now say what they do on hover, like the app's other icon buttons. Each tooltip reuses the button's accessible label, or the wording its twin uses elsewhere, in the app's existing tooltip chip.

What changes

• Comments. The "+" adder in diffs and Markdown previews says "Add comment" (crates/ui/src/comment_ui.rs:40), as does the file editor's gutter "+" (crates/ui/src/files/preview.rs:2927). The gutter's comment marker says "Show comment" or "Hide comment", by whether its comment is open (preview.rs:2893, :2903).
• Model picker. The Starred tab, each agent tab (named after its agent) and the favorite star ("Add to favorites" / "Remove from favorites") get tooltips (crates/ui/src/pickers.rs:4904, :4945, :5394), as does the compact picker's Back (crates/ui/src/pickers/compact.rs:524). The full picker shows the compact one's PickerHint chip, now pub(super) (compact.rs:1473), so both pickers' tooltips look the same.
• Pull requests. The board's search clear says "Clear search" (crates/ui/src/pull_requests.rs:2509). The comment box's send button says "Send comment", or "Sending comment" while a send is in flight, the same text as its accessible label (crates/ui/src/pull_request_interactions.rs:245, :425).
• Settings.
  • Appearance: an accent swatch shows its color's name (crates/ui/src/settings/appearance.rs:1903). The × on Add a theme and on Adjust background says "Close" (:2601, :3137), and the background zoom buttons say "Zoom out" and "Zoom in" (:3025, :3052).
  • Billing: the extra-credit pack stepper says "Fewer packs" / "More packs", now its accessible label too (crates/ui/src/settings/billing.rs:648, :664).
  • Cloud: the repositories refresh says "Check repositories again", and the GitHub device-code chip "Copy code" (crates/ui/src/settings/cloud.rs:1045, :1152).
  • Providers: the refresh says "Check for agents and updates" (crates/ui/src/settings/harnesses.rs:346).
• Shell. Add action's icon choices name their icon: Play, Test, Lint, Configure, Build, Debug (crates/ui/src/shell/actions_ui.rs:614). The section dialog's × says "Close" (crates/ui/src/shell/sidebar_sections.rs:866), the voice error's × "Dismiss" (crates/ui/src/shell/voice_stage.rs:249), and the "…" that folds New project's folder trail "Show hidden folders" (crates/ui/src/shell/spaces.rs:8351). That crumb's other tooltip, a crumb's full name past 26 characters (spaces.rs:8322, :8347), never applies to the fold, whose name is "…" (:8282), so no element gets two.
• Screenshots. docs/screenshots/icon-tooltips/ holds a full-window capture of each tooltip; its README lists them and says how they were taken.

Testing

• macOS 27.0.1, rustc 1.99.1: cargo test -p zeron-ui --lib -- --test-threads=1 at bdb4e0c4, rebased onto v0.2.124 (c04e3749): 1875 passed, 0 failed. Run in parallel, the suite aborts with SIGABRT on this Mac without this change too; CI runs it under nextest, one process per test.
• No test added. A throwaway gpui test, not committed, hovered the comment adder and saw its tooltip built, and failed with the tooltip line removed.
• Live, each of the 26 captures below, in the production Shell: an offscreen window that never took focus, synthetic pointer and key events, and an in-process engine. The account, the pull requests, Billing, Cloud and the model catalog came from faked engine replies. No step sent a comment, bought credits, wrote the clipboard or opened a URL, and the voice start failed before any audio device opened.
• git show --check: clean.
• Not run: dark mode; Windows and Linux; the buttons hovered by hand in the packaged app; "Sending comment", which shows only while a send is in flight.

All 26 tooltips

Add comment — "+" beside a Markdown table header

Add comment — "+" in a diff line's gutter

Add comment — "+" in the file editor's gutter

Show comment — Comment marker, comment closed

Hide comment — Comment marker, comment open

Starred — Model picker's star tab

Claude Code — Model picker's agent tab

Add to favorites — A model's star, off

Remove from favorites — A model's star, on

Back — Compact picker's back arrow

Clear search — × in the board's search

Send comment — Send in the Activity comment box

Orange — An accent swatch

Close — × on Add a theme

Close — × on Adjust background

Zoom out — − beside the zoom slider

Zoom in — + beside the zoom slider

Fewer packs — − on the extra-credit packs

More packs — + on the extra-credit packs

Check repositories again — Refresh beside Choose on GitHub

Copy code — GitHub device-code chip

Check for agents and updates — Refresh beside the device menu

Test — An icon choice in Add action

Close — × on New section

Dismiss — × on the voice error

Show hidden folders — "…" in New project's folder trail

---

^{Need help on this PR? Tag @codesmith-bot with what you need.}