## Stack
- **Current: #24489 [1 of 2]** - render markdown tables in app style.
- **Stacked follow-up: #24636 [2 of 2]** - render cramped markdown
tables as key/value records.
## Why
Markdown tables currently render as boxed terminal grids, which gives
ordinary assistant output a heavier visual treatment than surrounding
rich text. This row-separated layout is the best match for how the App
renders tables, while accented headers remain distinguishable even when
a terminal font renders bold subtly.
<table>
<tr><td>
<p align="center">Codex CLI - Before</p>
<img width="1722" height="742" alt="CleanShot 2026-05-25 at 18 46 17"
src="https://github.com/user-attachments/assets/f673d92a-ebd8-46e2-b414-3d985e41b6a4"
/>
</td></tr>
<tr><td>
<p align="center">Codex CLI - After</p>
<img width="1720" height="957" alt="image"
src="https://github.com/user-attachments/assets/36a3d331-bea1-439b-b5be-e97b0731bd6f"
/>
</td></tr>
<tr><td>
<p align="center">Codex App</p>
<img width="979" height="1293" alt="CleanShot 2026-05-25 at 18 45 04"
src="https://github.com/user-attachments/assets/7d97cae0-9256-4f6e-a4b3-8b8f22b0d901"
/>
</td></tr>
</table>
## What Changed
- Render markdown tables as padded, aligned rows without an enclosing
box.
- Style table headers with the active syntax-theme accent plus bold
text, while keeping separators low contrast and theme-aware.
- Use a segmented heavy header rule and thin body-row rules, preserving
wrapping, narrow-width fallback, streaming parity, and rich-history
rendering.
- Update focused assertions and snapshots for the final table layout.
## How to Test
1. Render a markdown table in the TUI with several rows and columns.
2. Confirm the header uses the active theme accent, rows use
one-character interior padding, and the table has no enclosing box.
3. Confirm the header is followed by segmented `━` rules and multiple
body rows are separated by muted segmented `─` rules.
4. Render the same table while streaming and in history/raw-mode
toggles; the final rich layout should remain stable.
5. Render a narrow table with long content and verify wrapping or pipe
fallback does not overflow.
## Validation
- `just test -p codex-tui table`
- `just test -p codex-tui streaming::controller::tests`
- `just argument-comment-lint-from-source -p codex-tui -- --all-targets`
- `just fix -p codex-tui`
- `just fmt`
`just test -p codex-tui` was also run after accepting the snapshots; it
fails only in the unrelated existing guardian app tests
`update_feature_flags_disabling_guardian_clears_review_policy_and_restores_default`
and
`update_feature_flags_disabling_guardian_clears_manual_review_policy_without_history`.
## Why
Numbered Markdown findings become hard to scan when long items visually
run together or when wrapped explanatory paragraphs lose their list
indentation. This is especially visible in review output: the next
number can look attached to the previous finding, and paragraph
continuation rows can jump back toward the left margin instead of
staying grouped beneath their item.
<table><tr><td>
<center>Before</center>
<img width="1718" height="836" alt="CleanShot 2026-05-24 at 14 00 49"
src="https://github.com/user-attachments/assets/f1ee0023-50fa-4f81-a641-ae08b17b99bd"
/>
</td></tr>
<tr><td>
<center>After</center>
<img width="1714" height="906" alt="image"
src="https://github.com/user-attachments/assets/b123a5e0-a232-47bf-96d5-c935295f7c0a"
/>
</td></tr>
</table>
## What Changed
- Insert a blank separator before a sibling list item when the previous
item occupies more than one rendered line.
- Preserve compact rendering for lists whose sibling items each render
on one line.
- Preserve list-body leading whitespace when transient streamed
assistant rows require another wrapping pass for history display, so
wrapped paragraphs stay aligned beneath their item.
- Share the existing leading-whitespace prefix logic used by history
insertion instead of introducing a second indentation rule.
- Keep streamed Markdown output aligned with completed rendering and add
snapshots for findings-style spacing and streamed paragraph indentation.
## How to Test
1. Start Codex from this branch and open the recorded repro session
`019e563f-7d58-7ff2-8ec7-828f20fa61ca`.
2. Inspect the numbered `Findings` list whose items contain explanatory
paragraphs.
3. Confirm each multiline finding is separated from the next numbered
finding by one blank line.
4. Confirm wrapped rows of each indented paragraph remain aligned
beneath the finding body, rather than returning to the left edge.
5. Render a short one-line numbered or unordered list and confirm its
items remain compact without added blank rows.
Targeted tests:
- `just test -p codex-tui history_cell insert_history markdown_render
markdown_stream streaming::controller`
- `just argument-comment-lint-from-source -p codex-tui`
## Related Work
PR #24346 changes Markdown table column allocation in parallel. This PR
is intentionally limited to list-item readability and history wrapping;
both branches touch `codex-rs/tui/src/markdown_render.rs`, so a small
merge conflict may need resolution depending on merge order.
## 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.
We don't instruct the model to use citations, so it never emits them.
Further, ratatui [doesn't currently support rendering links into the
terminal with OSC 8](https://github.com/ratatui/ratatui/issues/1028), so
even if we did parse citations, we can't correctly render them.
So, remove all the code related to rendering them.
## Summary
- Factor `load_config_as_toml` into `core::config_loader` so config
loading is reusable across callers.
- Layer `~/.codex/config.toml`, optional `~/.codex/managed_config.toml`,
and macOS managed preferences (base64) with recursive table merging and
scoped threads per source.
## Config Flow
```
Managed prefs (macOS profile: com.openai.codex/config_toml_base64)
▲
│
~/.codex/managed_config.toml │ (optional file-based override)
▲
│
~/.codex/config.toml (user-defined settings)
```
- The loader searches under the resolved `CODEX_HOME` directory
(defaults to `~/.codex`).
- Managed configs let administrators ship fleet-wide overrides via
device profiles which is useful for enforcing certain settings like
sandbox or approval defaults.
- For nested hash tables: overlays merge recursively. Child tables are
merged key-by-key, while scalar or array values replace the prior layer
entirely. This lets admins add or tweak individual fields without
clobbering unrelated user settings.
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.
The only file to watch is the cargo.toml
All the others come from just fix + a few manual small fix
The set of rules have been taken from the list of clippy rules
arbitrarily while trying to optimise the learning and style of the code
while limiting the loss of productivity
Also, simplify the streaming behavior.
This fixes a number of display issues with streaming markdown, and paves
the way for better markdown features (e.g. customizable styles, syntax
highlighting, markdown-aware wrapping).
Not currently supported:
- footnotes
- tables
- reference-style links
This was mostly written by codex under heavy guidance via test cases
drawn from logged session data and fuzzing. It also uncovered some bugs
in tui_markdown, which will in some cases split a list marker from the
list item content. We're not addressing those bugs for now.
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.
We wait until we have an entire newline, then format it with markdown and stream in to the UI. This reduces time to first token but is the right thing to do with our current rendering model IMO. Also lets us add word wrapping!