Skip to content

feat: lossless terminal output with on-demand retrieval #10944

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom
Open
hannesrudolph wants to merge 11 commits into
base: main
Choose a base branch
from
Open

feat: lossless terminal output with on-demand retrieval #10944

hannesrudolph wants to merge 11 commits into from

Conversation

@hannesrudolph
Copy link
Collaborator

@hannesrudolph hannesrudolph commented Jan 24, 2026 •
edited
Loading

image

Summary

Refactors terminal command output handling to preserve full output losslessly. Instead of truncating large outputs and losing information, Roo now saves complete output to disk and provides the LLM with a preview plus the ability to retrieve the full content on demand.

Closes #10941

Problem

Users experienced several pain points with the previous terminal output handling:

  • Lost output from long builds/tests: When running npm install, cargo build, test suites, or other commands that produce significant output, important error messages at the end could get truncated away
  • Confusing settings: Two separate sliders for "line limit" and "character limit" were difficult to understand and tune correctly
  • No recovery option: Once output was truncated, the LLM had no way to retrieve the lost information, often leading to missed errors or incomplete debugging

Solution

This PR implements a "persisted output" pattern:

  1. Lossless preservation: All command output is captured. When output exceeds the preview threshold, it's automatically saved to disk in the task's storage directory
  2. Smart previews: The LLM receives a configurable preview (2KB, 4KB, or 8KB) plus metadata about the full output size
  3. On-demand retrieval: A new read_command_output tool lets the LLM fetch the complete output or search for specific patterns when needed
  4. Automatic cleanup: Artifacts are cleaned up when tasks complete or when conversation history is rewound

User-Facing Changes

Settings

Before: Two confusing sliders

  • "Terminal Output Line Limit" (slider)
  • "Terminal Output Character Limit" (slider)

After: One simple dropdown

  • "Command output preview size" with options: Small (2KB), Medium (4KB), Large (8KB)

The new setting controls how much output Roo sees directly in the preview. Full output is always preserved and accessible.

How It Works

  1. You run a command (e.g., npm test)
  2. If output is small (under the preview threshold), it works exactly as before
  3. If output is large:
    • Full output is saved to a file in Roo's task storage
    • Roo sees a preview with a note about the full size
    • Roo can use read_command_output to view the full output or search for specific errors

Benefits

  • Lossless: Full output is always preserved—no more missing error messages from long builds
  • Searchable: Roo can search for specific patterns (like "error" or "failed") in large outputs
  • Simplified settings: One easy dropdown instead of two confusing sliders
  • Automatic cleanup: Artifacts are automatically cleaned up when tasks complete
  • Predictable context usage: Preview size is fixed and predictable, making context management easier

Technical Changes

  • New OutputInterceptor class: Buffers output and spills to disk when threshold exceeded
  • New read_command_output tool: Allows reading full output or searching for patterns
  • Updated ExecuteCommandTool: Uses the new interceptor pattern
  • Lifecycle management: Artifacts tied to conversation history, cleaned up on rewind/delete
  • Settings migration: Old slider settings replaced with new dropdown

Testing

  • 49 new tests covering the new functionality
  • Unit tests for OutputInterceptor (buffering, spilling, cleanup)
  • Unit tests for ReadCommandOutputTool (read, search, error cases)
  • Integration tests for the full flow
  • Manual testing of various scenarios (small output, large output, progress bars, errors)

@dosubot dosubot bot added size:XXL This PR changes 1000+ lines, ignoring generated files. Enhancement New feature or request labels Jan 24, 2026
@roomote
Copy link
Contributor

roomote bot commented Jan 24, 2026 •
edited
Loading

Oroocle Clock   Follow along on Roo Cloud

Re-review complete. No new issues found; all previously flagged items are resolved.

  • execute_command should respect terminalOutputPreviewSize
  • read_command_output native tool schema should not require optional params (search/offset/limit) under strict mode
  • Avoid allocating Buffer(offset) in read_command_output for large offsets (line-number calculation can blow up memory)
  • Bound accumulatedOutput growth in execute_command to avoid unbounded memory usage during long-running commands
Previous reviews

Mention @roomote in a comment to request specific changes to this pull request or fix all unresolved issues.

roomote[bot]
roomote bot reviewed Jan 24, 2026
View reviewed changes
roomote[bot]
roomote bot reviewed Jan 24, 2026
View reviewed changes
roomote[bot]
roomote bot reviewed Jan 24, 2026
View reviewed changes
@hannesrudolph hannesrudolph changed the title feat: add read_command_output tool for retrieving truncated command output feat: lossless terminal output with on-demand retrieval Jan 24, 2026
@roomote
Copy link
Contributor

roomote bot commented Jan 24, 2026 •
edited
Loading

Oroocle Clock   Follow along on Roo Cloud

Flagged a few correctness and contract issues to address before merge.

  • execute_command should respect terminalOutputPreviewSize (currently hardcoded to default)
  • read_command_output native tool schema should not require optional params (search/offset/limit) under strict mode
  • Avoid allocating Buffer(offset) in read_command_output for large offsets (line-number calculation can blow up memory)

Mention @roomote in a comment to request specific changes to this pull request or fix all unresolved issues.

roomote[bot]
roomote bot reviewed Jan 24, 2026
View reviewed changes
roomote[bot]
roomote bot reviewed Jan 24, 2026
View reviewed changes
roomote[bot]
roomote bot reviewed Jan 24, 2026
View reviewed changes
roomote[bot]
roomote bot reviewed Jan 24, 2026
View reviewed changes
hannesrudolph added a commit that referenced this pull request Jan 25, 2026
@hannesrudolph
fix: resolve CI failures for PR #10944
53939b6 
- Remove unused barrel file (src/integrations/terminal/index.ts) to fix knip check
- Fix Windows path test in OutputInterceptor.test.ts by using path.normalize()
- Add missing translations for terminal.outputPreviewSize settings to all 17 locales
@hannesrudolph
feat: add read_command_output tool for retrieving truncated command o…
1a8be4d 
…utput

Implements a new tool that allows the LLM to retrieve full command output
when execute_command produces output exceeding the preview threshold.

Key components:
- ReadCommandOutputTool: Reads persisted output with search/pagination
- OutputInterceptor: Intercepts and persists large command outputs to disk
- Terminal settings UI: Configuration for output interception behavior
- Type definitions for output interception settings

The tool supports:
- Reading full output beyond the truncated preview
- Search/filtering with regex patterns (like grep)
- Pagination through large outputs using offset/limit

Includes comprehensive tests for ReadCommandOutputTool and OutputInterceptor.
@hannesrudolph
fix: address PR review comments
2893261 
- Read terminalOutputPreviewSize from providerState instead of hardcoded default
- Fix native tool schema to only require artifact_id (optional params no longer required)
- Fix Buffer allocation for line numbers using chunked 64KB reads to avoid memory blowup
@hannesrudolph
fix: bound accumulatedOutput growth in execute_command
57666f3 
Prevent unbounded memory growth during long-running commands by trimming
the accumulated output buffer. The full output is preserved by the
OutputInterceptor; this buffer is only used for UI display.
@hannesrudolph
fix: resolve CI failures for PR #10944
e61dc7c 
- Remove unused barrel file (src/integrations/terminal/index.ts) to fix knip check
- Fix Windows path test in OutputInterceptor.test.ts by using path.normalize()
- Add missing translations for terminal.outputPreviewSize settings to all 17 locales
@hannesrudolph hannesrudolph force-pushed the feat/read-command-output-tool branch from 53939b6 to e61dc7c Compare January 27, 2026 01:43
@hannesrudolph
fix(parser): add read_command_output to NativeToolCallParser
33bff28 
chore: remove terminalCompressProgressBar setting

- Fix: Add missing read_command_output case to parser (was causing 'Invalid arguments' errors)
- Remove: Delete compress progress bar setting from all components (redundant with preview size control)
- Clean up: Remove from global-settings, OutputInterceptor, BaseTerminal, ExecuteCommandTool, SettingsView, TerminalSettings, ExtensionStateContext
- Clean up: Remove from all i18n locale files
@hannesrudolph
feat(ui): add read_command_output activity indicator
4125869 
Show read progress in chat when read_command_output tool is used:
- Display 'Roo read command output (0 B - 100 KB of 263.3 KB)'
- Shows the specific byte range being read each call
- Uses same visual style as read_file tool
- Add 'tool' to ClineSay types
- Add readCommandOutput to ClineSayTool with readStart/readEnd/totalBytes
@hannesrudolph
refactor: remove terminalOutputLineLimit and terminalOutputCharacterL…
b9b3ee4 
…imit settings

These settings were redundant with terminalOutputPreviewSize which controls
the preview shown to the LLM. The line/char limits were for UI truncation
which is now handled with hardcoded defaults (500 lines, 50K chars) since
they don't need to be user-configurable.

- Remove settings from packages/types schemas
- Remove DEFAULT_TERMINAL_OUTPUT_CHARACTER_LIMIT constant
- Update compressTerminalOutput() to use hardcoded limits
- Update ExecuteCommandTool to not pass limit parameters
- Update ClineProvider state handling
- Update webview context and settings
- Update tests to not use removed settings
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

@roomote roomote[bot] roomote[bot] approved these changes

@mrubens mrubens Awaiting requested review from mrubens mrubens is a code owner

@cte cte Awaiting requested review from cte cte is a code owner

@jr jr Awaiting requested review from jr jr is a code owner

At least 1 approving review is required to merge this pull request.

Assignees

No one assigned

Labels

Enhancement New feature or request size:XXL This PR changes 1000+ lines, ignoring generated files.

Projects

Roo Code Roadmap
Status: Triage

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

Terminal Output Handling Refactor: Persisted Output Pattern

2 participants

@hannesrudolph