Copilot CLI Updates & Release Notes

2026-05-23

Non-interactive subcommands (plugin list, mcp list, help, version) no longer consume stdin

Add vertical scrollbar with mouse drag support to the main conversation view

Switching to Autopilot mode no longer triggers unexpected permission prompts for tool, path, or URL access

copilot --continue from a session's saved directory now refreshes the saved branch and git context instead of leaving them stale

Kill command safety filter no longer rejects valid commands that contain shell redirection like kill -0 <PID> 2>/dev/null.

Sessions now resume in their saved working directory; pass -C to override. Flags whose values are relative paths (e.g. --attachment, --log-dir) resolve from the saved cwd.

Context window tier selection (default ~200K vs 1M tokens) is now enforced end-to-end, so picking a tier actually constrains compaction, truncation, and token display

AI Credits usage correctly displays after sessions using the Responses API

Rendering no longer stutters when using tmux on Cygwin or mintty

Slash command picker keeps (experimental) and (staff) labels orange when the row is selected

Reasoning tokens display as a parenthetical on output token count in the token usage summary

Sessions containing events with non-URL strings in URL/URI fields resume without a 'Session file is corrupted' error

Requests that time out due to an HTTP/2 upload stall automatically retry over HTTP/1.1

Sessions no longer fail to load on Windows when a process exits with a high-bit exit code (e.g., .NET unhandled exceptions)

Timeline entry connector color matches surrounding elements when expanded

Gray background bar no longer appears behind user messages on terminals without truecolor support

Status line command supports plain shell commands in addition to executable script paths

Automatically prune old process log files from ~/.copilot/logs/ at startup to prevent unbounded disk growth

Polish /statusline picker with cleaner item descriptions and better spacing

Picker checkboxes now use a single-cell ▣/▢ glyph for tighter, more consistent rows across pickers

Custom agents support opt-in deferred tool loading via deferred-tool-loading in agent frontmatter, enabling tool-search discovery for agents with large tool lists

Exit summary displays AI Credits label with correct spacing before the value

/restart and /update preserve the current session ID after restarting

Legacy nested oauth.clientId and oauth.callbackPort keys in MCP server configs are now migrated to the supported oauthClientId and auth.redirectPort keys instead of being silently dropped

MCP OAuth re-authentication honors the configured redirectPort

PowerShell division operator no longer triggers false 'Allow directory access' prompts on Windows

/compact accepts optional focus instructions to shape the compaction summary

General-purpose subagents use GPT-5.4 or GPT-5.5 when available

/usage shows quota progress bars for session and weekly limits

AI credits error messages updated with clearer language and a Manage budget link

Added

• Add vertical scrollbar with mouse drag support to the main conversation view

Fixed

• Switching to Autopilot mode no longer triggers unexpected permission prompts for tool, path, or URL access
• copilot --continue from a session's saved directory now refreshes the saved branch and git context instead of leaving them stale
• Kill command safety filter no longer rejects valid commands that contain shell redirection like kill -0 <PID> 2>/dev/null.
• Sessions now resume in their saved working directory; pass -C to override. Flags whose values are relative paths (e.g. --attachment, --log-dir) resolve from the saved cwd.

Added

Context window tier selection (default ~200K vs 1M tokens) is now enforced end-to-end, so picking a tier actually constrains compaction, truncation, and token display

Improved

Reasoning tokens display as a parenthetical on output token count in the token usage summary

Fixed

AI Credits usage correctly displays after sessions using the Responses API

Rendering no longer stutters when using tmux on Cygwin or mintty

Slash command picker keeps (experimental) and (staff) labels orange when the row is selected

Improved

• Status line command supports plain shell commands in addition to executable script paths
• Automatically prune old process log files from ~/.copilot/logs/ at startup to prevent unbounded disk growth
• Polish /statusline picker with cleaner item descriptions and better spacing
• Picker checkboxes now use a single-cell ▣/▢ glyph for tighter, more consistent rows across pickers

Fixed

• Sessions containing events with non-URL strings in URL/URI fields resume without a 'Session file is corrupted' error
• Requests that time out due to an HTTP/2 upload stall automatically retry over HTTP/1.1
• Sessions no longer fail to load on Windows when a process exits with a high-bit exit code (e.g., .NET unhandled exceptions)
• Timeline entry connector color matches surrounding elements when expanded
• Gray background bar no longer appears behind user messages on terminals without truecolor support

2026-05-20

--session-id=<id> resumes known sessions or tasks, and starts new sessions with a specific UUID

/remote commands now respect organization remote control and view from cloud policy and show a clear error when disabled

/remote command can now be used while the agent is working

Customizable status line in the terminal footer displays session info such as model, context window, git branch, and more

MCP tool loading at startup is faster for users with many HTTP-based MCP servers

Settings file no longer accumulates unrelated config keys when settings are updated

Add /security-review slash command to review code changes for security vulnerabilities (experimental)

Add preMcpToolCall hook for hook providers to control outgoing MCP request metadata

Add /chronicle cost-tips subcommand for personalized token usage and cost reduction recommendations

MCP servers using OAuth stay connected when authentication was performed in a separate session

GFM tables and blockquotes inside list items render correctly without a floating top border

Experimental mode indicator now appears persistently in the app header instead of as a one-time notification

Loading indicator color matches the active mode (plan, autopilot, shell)

Session naming works correctly for usage-based billing users

Pressing Enter on a highlighted subcommand completion inserts the selection instead of submitting the partial command

Use default release notes when publishing a release with no changelog entries

Editor launched with Ctrl+G no longer steals keystrokes or requires double keypresses

/memory show displays documentation links for learning about and managing Copilot Memory

Add terminalProgress setting to enable or disable OSC 9;4 terminal progress indicators

postToolUse hooks can now inject additionalContext into successful tool results

Only show remote session startup failure when remote mode is explicitly requested via --remote or enabled in user configuration

Shell tool calls succeed even when the model omits the description parameter

Ensure input token usage includes cached, update token formatting to clarify

Login prompt more clearly warns when token storage falls back to insecure plain text config file

GitHub MCP web search tool is available immediately without requiring tool search

Secret scanning now covers commit messages and PR descriptions, redacting secrets before they are published

Input area grows responsively with terminal height instead of capping at 3 lines

Added

• Add /security-review slash command to review code changes for security vulnerabilities
• Add preMcpToolCall hook for hook providers to control outgoing MCP request metadata
• Add /chronicle cost-tips subcommand for personalized token usage and cost reduction recommendations

Improved

• Experimental mode indicator now appears persistently in the app header instead of as a one-time notification
• Loading indicator color matches the active mode (plan, autopilot, shell)

Fixed

• MCP servers using OAuth stay connected when authentication was performed in a separate session
• GFM tables and blockquotes inside list items render correctly without a floating top border

2026-05-18

• postToolUse hook additionalContext is now injected as a system message for the model instead of being silently discarded
• Mouse clicks in the prompt correctly position cursor when input contains wide characters (CJK, emoji)
• Add /chronicle search subcommand to search all session content by keyword or topic
• /user switch reuses the fetched user list and shows a loading spinner on first open
• MCP servers using static OAuth clients correctly persist registration for token refreshes
• Add support for running the CLI on Alpine Linux (musl libc)
• Add /exit print option to print the session to the terminal before exiting
• Add /rubber-duck command to get an independent critique of the agent's current work
• Add /session id subcommand to display the current session ID and copy it to the clipboard
• Add auth.redirectPort config option for MCP servers to pin the OAuth callback to a fixed port
• Add /memory on|off|show slash command to enable, disable, or view memory status (persistent)
• Add copilot plugin update --all to update all installed plugins at once
• Add /rubber-duck command to invoke the rubber duck agent for an independent critique (experimental)
• Input prompt collapses to a single line when empty and grows naturally as you type
• File diffs are correctly reported to ACP clients for all edit tool types
• Repo hooks in .github/hooks/ now load in prompt mode (-p) when the folder is already trusted
• Fix extra line in timeline entries
• Box drawing and block characters render correctly on Windows terminals not using UTF-8 code page
• MCP server configurations with no args field are now accepted and treated as an empty args list
• Document attachment paths are included in context so the agent can reference pasted file paths, including Windows Copy as path inputs
• MCP stdio servers now display type as 'stdio' instead of 'local' for consistency
• Progress bar indicator now displays correctly in tmux sessions
• Experimental slash commands are now annotated with "(experimental)" in the help dialog and command picker
• Auto-update downloads the smaller platform-specific package instead of the universal one when available
• Auto-link GitHub issue and PR references (owner/repo#number) in assistant responses
• Prompt mode (-p) automatically loads workspace MCP sources when the current folder is already trusted
• Experimental: /mcp search command to search and install MCP servers from registry
• Experimental: Tool search with deferred loading for MCP and external tools
• Add "None" reasoning effort option to disable model reasoning in the reasoning effort picker
• Add COPILOT_PLUGIN_DIR_ONLY environment variable to disable automatic plugin discovery, enabling deterministic plugin sets when using --plugin-dir
• Copying text from the scroll view joins soft-wrapped lines without extra newlines or indentation
• Cursor positioning in input fields works correctly with wide characters (CJK, emoji)
• Hooks (preToolUse, postToolUse, subagentStart, subagentStop) now fire correctly for sub-agent tool calls
• Plugins loaded via --plugin-dir now correctly register their agents as available task(agent_type=...) subagents in prompt mode
• Memory storage correctly limits available scopes when no repository context is present
• --plugin-dir and --additional-mcp-config now work in --server / --headless mode
• Content-filtered model responses now display an explanation instead of a blank assistant turn
• PromptFrame UI now renders inside tmux when the outer terminal is ghostty, WezTerm, or kitty (detected via tmux list-clients).
• MCP OAuth token lookups are correctly scoped to the active session
• Memory permission prompts now name who can see a stored memory: user scope or the specific owner/repo for repository scope. Timeline entries also show the scope ((for user) / (shared with repository collaborators)).
• Reduce PowerShell syntax errors on Windows by avoiding && chaining instructions when using legacy PowerShell 5.x