VS Code Extension

Status: Current Last updated: 2026-05-11 18:58 EDT

Support tier: Public preview. VSIX bundles are published on GitHub Releases, not yet available from the VS Code Marketplace.

A full-featured CHAT editor for VS Code built on the Rust-powered chatter-lsp language server. Edit, validate, analyze, transcribe, and play back audio — all inside your editor. Leverages the same CHAT engine as the chatter CLI with live real-time feedback.

Platform support: Windows, macOS, and Linux

Installation

The extension is located in apps/vscode-extension/. Two install paths, depending on what you want to do.

End users — install a released VSIX. Pre-built, platform-specific VSIX bundles (each ships with the matching chatter-lsp binary) are published on GitHub Releases. Download the .vsix for your platform, then in VS Code: Extensions sidebar → “…” menu → Install from VSIX… and pick the downloaded file.

Developers — run from source. Open the apps/vscode-extension/ folder in VS Code, install dependencies, compile, and launch the Extension Development Host:

cd vscode
npm install
npm run compile
# Then press F5 in VS Code to launch the dev host

The dev host runs the locally-compiled extension and talks to a chatter-lsp binary discovered via the resolver described in the Configuration and Architecture sections below.

Validation & Diagnostics

Live Validation

Errors and warnings appear inline as you type — the same error codes as chatter validate (currently 191; verify with rg -c '#\[code\("[EW]' crates/core/talkbank-model/src/errors/codes/error_code.rs), with source-level precision:

• Squiggly underlines on the exact error location
• Problems panel integration with error codes and descriptions
• Validates on every keystroke (250ms debounce), plus immediately on open and save
• Filter by severity: all (default), errors only, or errors and warnings

Quick Fixes

Press Cmd+. (Mac) / Ctrl+. (Windows/Linux) to auto-fix common issues. Supports 21 error codes including:

• Add missing terminators, fix xx → xxx, insert undeclared speakers
• Swap reversed timestamps, close unclosed brackets, delete empty utterances
• Fix consecutive stress markers, consecutive commas, trailing-off markers

Inlay Hints

Inline annotations show alignment mismatches (e.g., [alignment: 3 main ↔ 2 mor]) and timing durations directly in the editor. Toggle with talkbank.inlayHints.enabled.

Validation Explorer

A tree view in the Explorer sidebar for bulk validation of entire directories. Runs the chatter validate CLI under the hood, caches results, and displays errors as navigable tree nodes. Right-click any folder to validate.

Cross-Tier Alignment Visualization

Hover

Hover over any word on the main tier to see its aligned morphological breakdown (%mor), grammatical relations (%gra), phonological form (%pho), and aligned items from %sin — all in a rich Markdown popup.

Hover works bidirectionally: hover a %mor item to see the aligned main-tier word.

Highlight Linking

Click any word on the main tier and all aligned items on dependent tiers light up. Click a %mor or %gra item and the corresponding main-tier word highlights. Bidirectional across %mor, %gra, %pho, %sin, %mod.

Dependency Graph

Cmd+Shift+G (Mac) / Ctrl+Shift+G (Windows/Linux) renders the %gra dependency tree for the utterance at your cursor. Words appear as labeled nodes with colored edges by relation type (subject, object, root, etc.). Rendered via Graphviz WASM — no internet required.

Toolbar: zoom, fit to window, export as SVG or PNG.

Media Playback

Single Segment

Cmd+Shift+Enter (Mac) / Ctrl+Shift+Enter (Windows/Linux) plays the timing bullet (•beg_end•) nearest the cursor. Audio/video resolves from the @Media: header.

Continuous Playback

Cmd+Shift+/ plays all segments from cursor to end of file. The editor cursor tracks the currently-playing utterance, auto-advancing through the transcript.

Playback Controls

Waveform View

Cmd+Shift+W opens an interactive waveform panel. Each timing bullet appears as a colored rectangle over the audio waveform. Click anywhere on the waveform to seek. Zoom in/out with buttons, slider, or mouse wheel. Auto-scrolls during playback.

Transcription Mode

A dedicated workflow for transcribing audio into CHAT format.

1. Start: talkbank.startTranscription — opens the media panel with the full audio file
2. Play: Audio plays from your cursor position
3. Stamp: Press F4 to insert a timing bullet at the current playback position and open a new *SPEAKER: line
4. Rewind: Press F8 to jump back and re-listen
5. Stop: talkbank.stopTranscription — exits transcription mode

Configure the default speaker code (talkbank.transcription.defaultSpeaker, default: “CHI”) and rewind duration.

Walker Mode

Step through utterances one at a time with synchronized audio playback.

Each step moves the editor cursor and optionally plays the corresponding audio segment. Configure auto-play, loop count (0 = infinite), pause between segments, and walk length.

CLAN Analysis Commands

Run any of the 34 CLAN analysis commands directly from VS Code — no terminal needed (see status-matrix.md for the authoritative list).

Right-click a .cha file or folder → Run Analysis → pick a command from the list:

• Frequency/Count: freq, mlu, mlt, wdlen, wdsize, maxwd, freqpos, timedur, vocd, …
• Syntax: complexity, dss, ipsyn, sugar, …
• Search: kwal, combo, …
• Assessment: kideval, eval, eval-d

Results appear in a dedicated panel with styled tables, stat cards, bar charts, and a CSV export button.

KidEval / Eval / Eval-D

Dedicated assessment panels for child language evaluation, general evaluation, and dementia assessment. Select language and normative database, filter by age and gender, and compare z-scores against population means.

Navigation

Editing

Code Completion

• Speaker codes (from @Participants)
• Dependent tier prefixes (%mor, %gra, %pho, etc.)
• Header names (triggers on @)
• Bracket annotations (triggers on [)
• Postcode punctuation

Snippets

8 built-in CHAT snippets: file header, @Participants, @ID, main tier, %mor, %gra, @Comment, Gem (@Bg/@Eg).

Participant Editor

talkbank.editParticipants opens a table editor for all @ID headers. Edit the 10 pipe-delimited fields (language, corpus, speaker, age, sex, group, SES, role, education, custom) in a form view. Changes are written back as canonical @ID lines.

Linked Editing

Edit a speaker code and all matching codes in the file update simultaneously.

Auto-Formatting

Format document rewrites to canonical CHAT format. On-type formatting auto-indents after tier prefixes.

Special Characters

Compose Mode

Type CA (Conversation Analysis) and CHAT special symbols without memorizing Unicode:

Press a key to insert the symbol. Press Escape to cancel. Status bar shows the active mode.

Coder Mode

Annotate transcripts with coding schemes from .cut files.

1. Start coder mode (context menu → “Start Coder Mode”)
2. Load a .cut codes file with hierarchical codes
3. Step through uncoded utterances (Cmd+Enter / Ctrl+Enter)
4. Insert codes from a hierarchical picker (Cmd+Shift+C / Ctrl+Shift+C)
5. Codes appear as %cod: tiers

Progress tracking shows how many utterances remain uncoded.

Speaker Filtering

Context menu → “Filter by Speaker…” opens a multi-select picker. Choose one or more speakers to create a filtered read-only view showing only those speakers’ utterance blocks, with all file headers preserved.

Code Lens

Utterance counts per speaker appear above the @Participants header (e.g., CHI: 42 utterances).

Additional Features

Configuration

Architecture

The extension launches the dedicated chatter-lsp binary over stdio using the Language Server Protocol. (chatter-lsp is a separate Rust crate at crates/chatter/chatter-lsp/; the VS Code extension’s executable resolver at apps/vscode-extension/src/executableService.ts looks for it in the bundled extension binary, then on PATH, then under the extension’s target directory.) The LSP server provides:

• Incremental parsing via tree-sitter
• Full validation (currently 191 error codes; see live count above)
• Cross-tier alignment computation
• CLAN analysis command execution
• Document formatting and symbol extraction

Interactive features (media playback, waveform, graphs, analysis panels, assessment tools) run as VS Code Webview panels with HTML/CSS/JS. The Graphviz renderer uses WASM — no external dependencies.

Development

cd vscode
npm install          # Install dependencies
npm run compile      # Build the extension
npm run watch        # Watch mode for development
npm test             # Run tests
npm run lint         # ESLint check

To debug: open the apps/vscode-extension/ folder in VS Code and press F5 to launch the Extension Development Host.