## Why
Streaming TUI responses repeatedly rendered the entire accumulated Markdown source for each committed delta, including blocks whose output could no longer change.
## What changed
- Retain rendered output for completed top-level Markdown blocks and rerender only the final mutable block as new source arrives.
- Track block boundaries during the existing Markdown parser pass and map them through table-fence normalization.
- Preserve canonical full rendering when source-wide state may affect earlier output, including reference link definitions and inline visualizations, and when the width or render mode changes.
- Append raw-mode lines directly while preserving blank lines.
## Testing
Added coverage that compares incremental output with full rendering across paragraphs, headings, lists, block quotes, code fences, tables, HTML blocks, links, visualizations, render-mode changes, and normalized table fences.
GitOrigin-RevId: 748171c4ed58923329b59c48ea3c2afa4819ec88
## Why
Wrapped URLs in rich TUI output, especially URLs rendered inside
Markdown tables, are split across terminal rows. In terminals that
support OSC 8 hyperlinks, treating each visible fragment as part of the
complete destination enables reliable open-link and copy-link actions
even after table layout wraps the URL.
This addresses the semantic-link portion of #12200 and the behavior
described in
https://github.com/openai/codex/issues/12200#issuecomment-4535452980. It
does not change ordinary drag-selection across bordered table rows.
## What Changed
- Added shared TUI OSC 8 support that validates `http://` and `https://`
destinations, sanitizes terminal payloads, and applies metadata
separately from visible line width/layout.
- Added semantic web-link annotations to assistant and proposed-plan
Markdown, including explicit web links and bare web URLs in prose and
table cells while excluding code and non-web Markdown destinations.
- Preserved complete URL targets through table wrapping, narrow pipe
fallback, streaming, transcript overlay rendering, history insertion,
and resize replay.
- Routed intentional Codex-owned links in notices,
status/setup/app-link, feedback, onboarding, MCP/plugin help, memories,
and update surfaces through the shared hyperlink handling.
## How to Test
1. Run Codex in a terminal with OSC 8 link support, such as Ghostty, and
request an assistant response containing a Markdown table whose last
column contains a long `https://` URL.
2. Make the terminal narrow enough for the URL to wrap across multiple
bordered table rows.
3. Use the terminal's open-link or copy-link action on more than one
wrapped URL fragment and confirm each fragment resolves to the complete
original URL.
4. Resize the terminal after the table is rendered and repeat the link
action to confirm the destination survives scrollback replay.
5. Open the transcript overlay while rich output is present and confirm
web links remain interactive there.
6. As a regression check, render inline/fenced code containing URL text
and a Markdown link such as
`[https://example.com](mailto:support@example.com)`; confirm these do
not acquire a web OSC 8 destination.
Targeted automated coverage exercised Markdown links and exclusions,
wrapped and pipe-fallback tables, streaming/transcript overlay
propagation, status-link truncation, and rendered word-wrapping cell
alignment. `just test -p codex-tui` was also run; it passed the
hyperlink coverage and reproduced two unrelated existing guardian
feature-flag test failures.
## Why
The TUI currently treats Markdown tables as ordinary wrapped text, which
makes table-heavy responses hard to read and brittle across narrow panes
and terminal resizes.
This change teaches the TUI to render Markdown tables responsively while
preserving the raw Markdown source needed to re-render streamed and
finalized transcript content after width changes. The goal is to keep
tables legible during streaming, after resize, and once a turn has
finished, without corrupting scrollback ordering.
## What Changed
- add table detection and responsive table rendering in the Markdown
renderer
- render standard tables with Unicode box-drawing borders when the pane
is wide enough
- add a vertical readability fallback for constrained or dense tables so
narrow panes still show each row clearly
- keep links and `<br>` content inside table cells instead of leaking
text outside the table
- avoid table normalization inside fenced or indented code blocks
- preserve raw streamed Markdown source and keep the active table as a
mutable tail until finalization
- consolidate finalized streamed content into source-backed transcript
cells so post-resize re-rendering stays correct
- add snapshot and targeted streaming/resize regression coverage for the
new table behavior
## How to Test
1. Start Codex TUI from this branch.
2. Paste this exact prompt:
`This is a session to test codex, no need to do any thinking, just end
different markdown tables, with columns exploring different markdown
contents, like links, bold italic, code, etc. Make them different sizes,
some 30+ rows, some not and intertwine them with some paragraphs with
complex formatting as well.`
3. Confirm the response includes several Markdown tables mixed with
richly formatted paragraphs.
4. Confirm wide-enough tables render with box-drawing borders instead of
plain wrapped pipe text.
5. Resize the terminal narrower while the answer is still streaming and
confirm the in-progress table stays coherent instead of duplicating
headers or leaving broken scrollback behind.
6. Resize again after the turn finishes and confirm the finalized
transcript re-renders cleanly at the new width.
7. In a narrow pane, verify dense tables fall back to the vertical
per-row layout instead of producing unreadable wrapped columns.
8. Also verify pipe-heavy fenced code blocks still render as code, not
as tables.
Targeted tests:
- `cargo test -p codex-tui table_readability_fallback --no-fail-fast`
- `cargo test -p codex-tui markdown_render --no-fail-fast`
- `cargo test -p codex-tui streaming::controller --no-fail-fast`
- `cargo test -p codex-tui table_resize_lifecycle --no-fail-fast`
## Docs
No developer docs update appears necessary.
Fixes multiple scrollback and terminal resize issues: #5538, #5576,
#8352, #12223, #16165, and #15380.
## Why
Codex writes finalized transcript output into terminal scrollback after
wrapping it for the current viewport width. A later terminal resize
could leave that scrollback shaped for the old width, so wider windows
kept narrow output and narrower windows could show stale wrapping
artifacts until enough new output replaced the visible area.
This is also the foundation PR for responsive markdown tables. Table
rendering needs finalized transcript content to be width-sensitive after
insertion, not only while content is first streaming. Markdown table
rendering itself stays in #18576.
## Stack
- PR1: resize backlog reflow and interrupt cleanup
- #18576: markdown table support
## What Changed
- Rebuild source-backed transcript history when the terminal width
changes. `terminal_resize_reflow` is introduced through the experimental
feature system, but is enabled by default for this rollout so we can
validate behavior across real terminals.
- Preserve assistant and plan stream source so finalized streaming
output can participate in resize reflow after consolidation.
- Debounce resize work, but force a final source-backed reflow when a
resize happened during active or unconsolidated streaming output.
- Clear stale pending history lines on resize so old-width wrapped
output is not emitted just before rebuilt scrollback.
- Bound replay work with `[tui.terminal_resize_reflow].max_rows`:
omitted uses terminal-specific defaults, `0` keeps all rendered rows,
and a positive value sets an explicit cap. The cap applies both while
initially replaying a resumed transcript into scrollback and when
rebuilding scrollback after terminal resize.
- Consolidate interrupted assistant streams before cleanup, then clear
pending stream output and active-tail state consistently.
- Move resize reflow and thread event buffering helpers out of `app.rs`
into dedicated TUI modules.
- Add focused coverage for resize reflow, feature-gated behavior,
streaming source preservation, interrupted output cleanup,
unicode-neutral text, terminal-specific row caps, and composer/layout
stability.
## Runtime Bounds
Resize reflow keeps only the most recent rendered rows when a row cap is
active. The default is `auto`, which maps to the detected terminal's
default scrollback size where Codex can identify it: VS Code `1000`,
Windows Terminal `9001`, WezTerm `3500`, and Alacritty `10000`.
Terminals without a dedicated mapping use the conservative fallback of
`1000` rows. Users can override this with `[tui.terminal_resize_reflow]
max_rows = N`, or set `max_rows = 0` to disable row limiting.
## Validation
- `just fmt`
- `git diff --check`
- `cargo test --manifest-path codex-rs/Cargo.toml -p codex-tui reflow`
- `cargo test --manifest-path codex-rs/Cargo.toml -p codex-tui
transcript_reflow`
- `just fix -p codex-tui`
- PR CI in progress on the squashed branch
This is a follow-up to https://github.com/openai/codex/pull/15922. That
previous PR deleted the old `tui` directory and left the new
`tui_app_server` directory in place. This PR renames `tui_app_server` to
`tui` and fixes up all references.
This is the part 1 of 2 PRs that will delete the `tui` /
`tui_app_server` split. This part simply deletes the existing `tui`
directory and marks the `tui_app_server` feature flag as removed. I left
the `tui_app_server` feature flag in place for now so its presence
doesn't result in an error. It is simply ignored.
Part 2 will rename the `tui_app_server` directory `tui`. I did this as
two parts to reduce visible code churn.
## Summary
- preserve baseline streaming behavior (smooth mode still commits one
line per 50ms tick)
- extract adaptive chunking policy and commit-tick orchestration from
ChatWidget into `streaming/chunking.rs` and `streaming/commit_tick.rs`
- add hysteresis-based catch-up behavior with bounded batch draining to
reduce queue lag without bursty single-frame jumps
- document policy behavior, tuning guidance, and debug flow in rustdoc +
docs
## Testing
- just fmt
- cargo test -p codex-tui
This eliminates a "bounce" at the end of streaming where we hide the
status indicator at the end of the turn and the composer moves up two
lines.
Also, simplify streaming further by removing the HistorySink and
inverting control, and collapsing a few single-element structures.
Sometimes COT is returns as text content instead of `ReasoningText`. We
should parse it but not serialize back on requests.
---------
Co-authored-by: Ahmed Ibrahim <aibrahim@openai.com>
Wait for newlines, then render markdown on a line by line basis. Word wrap it for the current terminal size and then spit it out line by line into the UI. Also adds tests and fixes some UI regressions.
Charlie Marsh