Changelog

This page tracks user-facing changes to Cosine CLI.

Unreleased

No unreleased changes yet.

v2.0.0-beta21

Changes since v2.0.0-beta20 (published 2026-03-10).

New Features

• Added GitHub Copilot sign-in with cos login-with-copilot, so you can connect your Copilot account from the CLI and use Copilot-backed models directly in Cosine.
• You can now queue follow-up prompts while a run is still active. Nudges and queued prompts are shown separately, and queued items stay visible in the timeline until they run.
• Added /link-project so you can attach another project to the current session, with an option to save that linked project for future sessions in the same workspace.
• Tool approvals are now more informative: edit-like tool calls can show a diff preview before approval, and approval cards use clearer user-facing descriptions.
• Expanded the model picker with updated model options, including GPT 5.4, GPT 5.4 1M, and GitHub Copilot-backed choices, while making model selection behave more consistently across settings and task prompts.

Fixes

• Fixed image path detection so pasted paths still work when they are quoted or followed by trailing punctuation.
• Fixed remote runtime host override handling so custom hosts are respected more consistently.
• Fixed remote runtime configuration selection and write-location issues.
• Fixed queued prompt handling so stacked items lay out correctly and stale completion events do not accidentally drain the queue.
• Fixed interrupted-run UI so cancellations are shown more cleanly.

v2.0.0-beta19

Changes since v2.0.0-beta18 (published 2026-03-07).

New Features

• Added a diff viewer to the Git Session Manager so you can inspect checkpoint changes without leaving the CLI.
• Swarm mode now lets you turn QA verification agents on or off with /swarm-qa or from the command menu.
• Subagents now share MCP and LSP context more reliably with their parent session, reducing setup friction in Swarm workflows.
• Added initial support for sandbox-backed remote environments in managed runtime flows.

Changed

• The project initialization dialog now includes a “No, not this time” option so you can skip setup and continue immediately.

Fixes

• Fixed ANSI terminal rendering issues.
• Fixed shifted number and symbol keys in VS Code terminal input.
• Fixed nested subagents appearing under the wrong parent in the Agents panel.
• Fixed UI state bleed-through between active and background agents in multi-agent sessions.
• Fixed a background-task scheduling issue that could cause Swarm runs to return early.

v2.0.0-beta18

Changes since v2.0.0-beta17 (published 2026-03-05).

New Features

• Added Lua plugin support with cos plugin install, cos plugin list, and cos plugin remove, plus a plugin runtime that can subscribe to agent events, queue nudges, make HTTP requests, and perform sandboxed file operations.
• Added plugin documentation covering installation, the Lua API, lifecycle, and example plugins.
• Added xhigh reasoning support for GPT-5.4 in the CLI reasoning-effort controls.
• Swarm can now nudge active work and surface semi-async subagent progress so long-running tasks feel more responsive.

Changed

• cos update now automatically runs the installer for non-Homebrew installs, reducing the manual steps after an upgrade.
• The slash-command menu has been cleaned up for faster navigation and clearer command discovery.
• Plugin logs are now surfaced in the CLI panels so plugin activity is easier to inspect while debugging.
• Lumen and Devstral have been removed from the CLI model picker.

Fixes

• Resolved a subagent hang that could affect VS Code-hosted CLI sessions backed by CLI2.

beta15

Changes since beta14 (published 2026-03-04).

New Features

• Added automatic task name derivation from user prompts in the Agents sidepanel to make multi-agent sessions easier to scan.
• Expanded CLI2 event coverage to improve telemetry and product insights.

Fixes

• Fixed additional Swarm mode issues to improve stability in parallel subagent workflows.

v2.0.0-beta13

Changes since v2.0.0-beta12 (published 2026-03-03).

Fixes

• Fixed update check functionality to properly detect and prompt for new CLI versions.
• Fixed Swarm mode bugs including subagent checkpointing issues that could cause state inconsistencies.
• Fixed terminal display issues where the terminal could appear white or unresponsive.
• Fixed backspace behavior in filter dialogs — Ctrl+H now works correctly as backspace.
• Fixed user question handling on subagents so prompts are properly routed when using parallel agent workflows.
• Improved Homebrew install detection on Windows CI environments.

v2.0.0-beta12

Changes since v2.0.0-beta10 (published 2026-02-25).

New Features

Swarm Mode

Swarm mode enables parallel agent workflows by allowing the primary agent to spawn and orchestrate multiple subagents simultaneously. When activated, the agent can delegate independent tasks to subagents that run in parallel, significantly speeding up complex multi-file operations. Subagents appear in the Agents panel (Ctrl+3 / Alt+3) indented under their parent, where you can monitor progress, view diffs, or kill individual agents. This is particularly useful for large refactoring tasks, cross-module changes, or when you need multiple independent investigations running concurrently.

Light Mode

The CLI now supports a complete light color theme alongside the existing dark theme. Light Mode provides better visibility in bright environments and reduces eye strain during daytime usage. The theme automatically applies to all UI components including the timeline, side panels, dialogs, and terminal views. You can switch between themes through the settings or use the quick toggle in the commands menu.

Rebase Quick Action in Git Session Manager

A new Rebase action has been added to the Git Session Manager, allowing you to quickly rebase your current branch without leaving the CLI interface. This streamlines common git workflows when working with agent-generated branches, making it easier to keep feature branches up to date with main before merging or continuing work.

Auto-Approve Plan Functionality

Plan mode now supports auto-approve, which automatically approves the generated plan without requiring manual confirmation for each step. This is ideal when you want the agent to create and execute a plan in one flow while still benefiting from the structured planning phase. The setting can be toggled per-session or configured globally for users who prefer the plan-then-execute workflow without interruptions.

Standardized Plan File Context Injection

Plan files are now injected into the agent’s context more consistently and reliably. When a plan is created, its content is properly formatted and made available to the agent throughout the session. This ensures the agent always has access to the full plan context when making edits, reducing drift between the intended plan and actual execution.

Open Terminal Action in the Terminal User Interface (TUI)

You can now open an interactive terminal session directly from the TUI using the new Open Terminal action. Accessible from the commands menu (/ or Ctrl+P), this creates a new shell session without leaving your current conversation. The terminal appears in the Terminals panel (Ctrl+2 / Alt+2) where you can switch between it and your chat session seamlessly.

Send Terminal Output to Model

Terminal output can now be sent directly back to the model as context. After running commands in an interactive terminal, you can capture the output and include it in your conversation with the agent. This eliminates manual copy-pasting when sharing command results, error messages, or logs with Cosine.

Implementation Plans in Chat Timeline

When the agent creates a plan, it now appears inline in the chat timeline as a structured implementation plan block. These plans are collapsible, show completion status, and can be referenced throughout the conversation. This makes it easier to track what the agent intends to do and check off items as they’re completed.

Native Gemini Streaming Responses

The CLI now supports native streaming responses from Google’s Gemini models. This provides real-time token-by-token output for Gemini-backed conversations, reducing perceived latency and allowing you to see responses as they’re generated rather than waiting for complete responses.

Improved Text Selection and Copy UI

Text selection in the timeline has been significantly improved. You can now select and copy text from assistant responses more reliably, with better visual feedback during selection. The copy UI has been updated to provide clearer confirmation when text is copied to the clipboard, making it easier to extract code snippets, explanations, or other content from agent responses.

Fixes

• Fixed hangs that could occur during websocket inference.
• Fixed rendering issues where output_text assistant messages could display incorrectly.
• Fixed message ordering in resumed sessions so tool execution blocks and assistant output are interleaved correctly.
• Fixed a ggrep mutex issue that could cause instability.
• Removed stray debug logs from the terminal popout dialog.
• Fixed stale tool definitions after model switches by invalidating cache correctly.
• Fixed terminal overlay responsiveness issues.
• Fixed dialog search behavior so Ctrl+H works as backspace.
• Fixed Linux CGO build/linking reliability by switching to external linker mode.

Performance

• Improved CLI2 CGO build speed by roughly 3x.
• Added improved generation/stream telemetry (including trace, latency, and TTFT capture) to improve performance observability.