Feat markdown rendering

[simongdavies]

This pull request adds support for terminal markdown rendering of LLM output, improves file link handling, and enhances CLI and command features. The main improvements include integrating the marked and marked-terminal libraries to render markdown as ANSI-formatted output, introducing new CLI flags and commands for markdown and file management, and refining tool execution feedback. These changes significantly improve the readability and usability of LLM responses in the terminal.

Markdown Rendering and CLI Enhancements:

• Added marked and marked-terminal dependencies and integrated a new markdown-renderer.ts module to render LLM markdown output as ANSI-formatted terminal output, improving readability for structured responses. Also included a heuristic to detect markdown content and a post-processor to convert file references into clickable links.
• Introduced new CLI flags (--markdown, --no-markdown, --md, --no-md) to toggle markdown rendering, with the feature enabled by default. Updated CLI config and help text accordingly.
• Added a /markdown command to toggle markdown rendering at runtime, with detailed help text explaining the effects and defaults.

File Link and Session File Management:

• Implemented a post-processor to convert [[file:path]] markers in LLM output into clickable OSC 8 terminal hyperlinks and registered file references for session management.
• Added /files and /open slash commands to list and open files produced during the session, with corresponding help entries.

Tool Execution and Output Improvements:

• Improved tool execution feedback: tool names are now shown explicitly, and for sandbox tools (execute_javascript, execute_bash), results are rendered as markdown if enabled, or dimmed otherwise. Large JSON outputs are wrapped in code blocks for better formatting. (src/agent/event-handler.ts

Other Notable Changes:

• Added terminal hyperlink and file path formatting utilities to the ANSI helper (src/agent/ansi.ts
• Added a utility to format configuration summaries as markdown tables for improved display in markdown mode. (src/agent/slash-commands.ts

Build and Bash Interpreter Updates:

• Added a stub for node:module to support createRequire() in the bash interpreter sandbox, and updated the bash bundle build process and metadata.
• Improved error handling in the bash bundle build script to fail hard in CI if the build fails, preventing stale bundles.

[Copilot]

Pull request overview

Adds opt-in (default-on) terminal markdown rendering for LLM output via marked + marked-terminal, plus session file tracking (/files, /open, [[file:...]] markers), a /markdown toggle, refactored tool-output handling that splits "what gets saved to disk" from "what the LLM sees", and a few build/CLI/event-handler tweaks.

Changes:

• New markdown-renderer.ts, --markdown/--md CLI flags, /markdown slash command, and markdown rendering of LLM responses, code blocks, and selected tool/config output.
• New state.producedFiles tracking, [[file:path]] linkification, and /files + /open commands; refactored execute_javascript/execute_bash large-output paths around a new wrapToolResult helper and shared DISK_SAVE_THRESHOLD_BYTES / MAX_LLM_RESULT_CHARS.
• Bash bundle build now adds a node:module stub and fails CI on bundle errors; CI startup logs gated behind --verbose.

Reviewed changes

Copilot reviewed 14 out of 16 changed files in this pull request and generated 16 comments.

Show a summary per file

File	Description
src/agent/markdown-renderer.ts	New module: marked + marked-terminal wrapper, markdown heuristic, and [[file:...]] linkifier.
src/agent/index.ts	Tool-output refactor, wrapToolResult, file tracking, markdown rendering in main loop and banner, verbose-gated startup logs.
src/agent/event-handler.ts	Tool execution UX changes: unified tool label, non-verbose path prints only ✅ Done, markdown rendering of string/JSON results.
src/agent/slash-commands.ts	New /markdown, /files, /open; table-based /config; markdown tables in plugin configure flows; some error-string concatenation tweaks.
src/agent/state.ts	Adds markdownEnabled and producedFiles to AgentState.
src/agent/cli-parser.ts	Adds markdown CLI flag with env default and --markdown/--no-markdown/--md/--no-md.
src/agent/commands.ts	Help entries for /markdown, /files, /open.
src/agent/system-message.ts	Adds markdownEnabled to system prompt; injects OUTPUT mode and FILE REFERENCES instructions.
src/agent/ansi.ts	Adds C.link (OSC 8) and C.fileLink helpers.
scripts/build-modules.js	Fail-hard in CI on bash bundle build failure.
scripts/bash-bundle/build.mjs	Adds node:module alias to module-stub.
scripts/bash-bundle/module-stub.mjs	New stub exporting a fake createRequire.
builtin-modules/bash.json	Updated sourceHash for the rebuilt bundle.
package.json	Adds marked, marked-terminal, @types/marked-terminal.
package-lock.json	Adds new deps; also contains many unrelated upgrades/downgrades and missing-integrity entries.
.gitignore	Removes a stray malformed entry; keeps _tmp_bundle.js ignore.

Comments suppressed due to low confidence (1)

src/agent/index.ts:5990

• linkifyFiles is applied to the post-rendered markdown string. renderMarkdown may surround text with ANSI reset/styling escape sequences (e.g. inside list items, headings, or paragraphs), which can split a [[file:path]] literal if marked decides any character within is a markdown token (e.g. a * or backtick inside the path). Consider running linkifyFiles on the raw markdown text first (replacing markers with a stable plain-text placeholder), then passing the result through renderMarkdown, or vice-versa with a more tolerant regex.

    if (state.markdownEnabled && state.streamedText) {
      // Markdown mode: output was buffered (not streamed). Render now.
      let rendered = renderMarkdown(state.streamedText);
      rendered = linkifyFiles(rendered, fsWriteBase, trackFile);
      console.log(rendered);