claude-acp agent server not registered after every Zed restart

[tonku321]

Reproduction steps

1. Update to Zed Preview v0.227.0 (no extensions or custom agent configuration)
2. Use Claude Agent — works fine initially
3. Restart Zed
4. Open Agent Panel and try to start a new Claude Agent thread

Current vs. Expected behavior

Current behavior:
After every restart, the following error appears: Custom agent server claude-acp is not registered
The agent fails to start. Simply reinstalling Zed does not fix the issue.

Expected behavior:
Claude Agent should register correctly on every Zed startup without requiring reinstallation.

Workaround:

1. Uninstall Zed
2. Manually remove ~/Library/Application Support/Zed/
3. Manually uninstall claude-code
4. Install stable Zed release

Zed version and system specs

Zed: v0.227.0 (Preview)
OS: macOS Tahoe

Attach Zed log file

Zed.log

Relevant Zed settings

settings.json

{
	"vim_mode": true,
	"vim": { "use_system_clipboard": "always" },

	"status_bar": {
		"active_language_button": false,
		"experimental.show": true,
	},
	"global_lsp_settings": { "button": false },

	"theme": "tonku",

	// font ui
	"ui_font_family": "JetBrains Mono",
	"ui_font_size": 13,

	// font
	"buffer_font_family": "JetBrains Mono",
	"buffer_font_size": 11,
	"buffer_line_height": "comfortable",
	"buffer_font_features": { "calt": false },

	"tab_size": 4,
	"cursor_blink": false,
	"current_line_highlight": "none",
	"hard_tabs": true,
	"ensure_final_newline_on_save": false,
	"remove_trailing_whitespace_on_save": true,

	"unstable.ui_density": "compact",
	"toolbar": {
		"breadcrumbs": false,
		"quick_actions": false,
		"selections_menu": false,
	},
	"gutter": {
		"line_numbers": true,
		"folds": false,
		"runnables": false,
		"breakpoints": false,
	},

	"show_signature_help_after_edits": true,
	"inline_code_actions": false,
	"inlay_hints": { "enabled": false, "show_parameter_hints": false },

	"close_on_file_delete": true,
	"extend_comment_on_newline": false,
	"on_last_window_closed": null,
	"restore_on_file_reopen": false,

	"debugger": { "button": false },
	"collaboration_panel": { "button": false },

	"scrollbar": {
		"axes": { "horizontal": false },
		"cursors": false,
		"show": "always",
		"git_diff": false,
	},

	"project_panel": {
		"auto_fold_dirs": false,
		"sticky_scroll": false,
		"scrollbar": { "show": "never" },
		"git_status": false,
		"indent_guides": { "show": "never" },
		"dock": "right",
		"indent_size": 15,
	},
	"show_call_status_icon": false,

	"tab_bar": { "show_tab_bar_buttons": false },
	"tabs": {
		"file_icons": true,
		"activate_on_close": "left_neighbour",
		"show_close_button": "hover",
	},

	"outline_panel": {
		"button": false,
		"dock": "right",
		"indent_guides": { "show": "never" },
		"indent_size": 15,
		"expand_outlines_with_depth": 1,
		"folder_icons": false,
		"file_icons": false,
		"scrollbar": { "show": "never" },
		"git_status": false,
	},

	"notification_panel": { "button": false },
	"terminal": {
		"font_family": "JetBrains Mono",
		"font_size": 11,
		"cursor_shape": "bar",
		"blinking": "off",
		"dock": "bottom",
		"button": false,
		"line_height": "comfortable",
		"minimum_contrast": 0,
	},

	"agent": {
		"single_file_review": true,
		"message_editor_min_lines": 4,
		"button": true,
		"enabled": true,
		"dock": "left",
		"show_turn_stats": true,
		"default_profile": "write",
	},

	"agent_ui_font_size": 13,
	"agent_buffer_font_size": 11,

	"context_servers": {
		"mcp-server-github": {
   "command": "npx",
			"args": ["-y", "@modelcontextprotocol/server-github"]
		},
		"atlassian-mcp": {
   "command": "uvx",
			"args": ["--python=3.12", "mcp-atlassian"]
		},
		"chrome-devtools": {
   "command": "npx",
			"args": ["chrome-devtools-mcp@latest", "--autoConnect", "--experimentalVision"]
		},
		"mattermost": {
   "command": "npx",
			"args": ["-y", "@dakatan/mcp-mattermost"],
		}
	},

	"show_edit_predictions": true,
	"edit_predictions": {
		"provider": "zed",
		"mode": "subtle",
	},

	"session": {
		"restore_unsaved_buffers": false,
		"trust_all_worktrees": true,
	},

	"preview": {
		"restore_on_startup": "last_workspace",
		"ensure_final_newline_on_save": false,
	},

	"git": {
		"inline_blame": { "enabled": false },
		"git_gutter": "tracked_files",
	},
	"git_panel": {
		"button": false,
		"dock": null
	},
	"diff_view_style": "unified",

	"format_on_save": "off",

	"search": { "button": false },
	"use_smartcase_search": true,

	"title_bar": { "show_user_picture": true, "show_sign_in": true },

	"drag_and_drop_selection": { "enabled": false },

	"scroll_beyond_last_line": "off",
	"lsp_highlight_debounce": 0,

	"minimap": { "show": "never", "current_line_highlight": "all" },
	"preview_tabs": { "enabled": true, "enable_preview_from_file_finder": true },
	"vertical_scroll_margin": 5,
	"excerpt_context_lines": 7,
	"expand_excerpt_lines": 15,
	"minimum_contrast_for_highlights": 0,
	"show_whitespaces": "none",

	"languages": {
		"TypeScript": {
			"language_servers": ["!typescript-language-server", "!tailwindcss-language-server", "..."]
		},
		"TSX": {
			"language_servers": ["!typescript-language-server", "!tailwindcss-language-server", "..."]
		},
		"Go": {
			"format_on_save": "off"
		}
	},
	"lsp": {
		"vtsls": { "settings": { "typescript": { "preferences": { "importModuleSpecifier": "non-relative" } } } }
	}
}

Relevant Keymap

keymap.json

(for AI issues) Model provider details

• Provider: Claude Agent

If you are using WSL on Windows, what flavor of Linux are you using?

None

[Shivansh-25]

@esthertrapadoux I'd love to look into this for repro as I recently looked into another issue related to claude acp

[yeskunall]

@Shivansh-25 if you want to repro issues, go for it! You do not need to wait to be assigned one in this case. You can just leave a note here for others so they know someone else is on top of it!

Thanks again, man!

[Shivansh-25]

@tonku321 I am unable to reproduce the exact same issue. I am on the same version and tried restarting Zed several times and opening a new thread with the Claude agent. It worked fine all of the times. Can you please share a video or the logs (you can find the option in the command palette)

[oliverbarnes]

Can't reproduce either, with the caveat that mine is a different scenario from the OP's: I don't have a Claude subscription (I use Zed's).

Claude Agent loads and at first and shows me an authentication error when I try to send it a prompt, then after restarting Zed, the thread just shows me the option to /login.

Zed: v0.228.0+dev.0e5b4e13517dce72d62399f2e9d3247f8bec66df (Zed Dev 0e5b4e1) (Taylor's Version)
OS: macOS 26.3
Memory: 24 GiB
Architecture: aarch64

[Shivansh-25]

@tonku321 Let me know if you are still facing that issue. If it is fixed we can close this issue.

[yeskunall]

@tonku321 can you post your Zed logs? I doubt there’ll be anything useful there, but still. I think I know what’s happening --

It’s a startup race condition. On restart, Zed does two things concurrently:

1. Loads the agent registry (the catalog of available agents like claude-acp) from disk -- this is async and takes a moment.
2. Restores your previous workspace, including the agent panel with claude-acp selected -- this tries to connect immediately.

The connect attempt fires before the registry has finished loading, so when it looks up claude-acp, it’s not there yet. There is a retry mechanism that’s supposed to handle this, but it has a timing gap.

If it works the first time, it’s likely because you have to manually pick Claude Agent from the dropdown -- by then, Zed has had plenty of time to load. On restart, the workspace auto-restores and tries to connect instantly, before the registry is ready.

--

Reproducing this consistently is going to a be bit hard, but LMK if anyone is able to somehow do it. Thanks!

[tonku321]

I initially encountered this bug on Zed Preview, then cleared all data (workaround) and switched to Zed Stable for the day. Now that I've installed Zed Preview again, I can no longer reproduce it.

However, when I first hit this issue, I restarted Zed Preview about 10 times in a row and got the same error every single time — so I'm not entirely sure this is a race condition, as it was 100% reproducible for me at that point.

I'll keep trying to reproduce it, and if I manage to trigger it again, I'll provide more details (logs, etc.).