block · gudnuf · Jul 9, 2026
@@ -9,7 +9,7 @@ Buzz Relay ──WS──→ buzz-acp ──stdio──→ Your Agent
                                        (send_message, etc.)
 ```
 
-Supports any agent that speaks [ACP](https://agentclientprotocol.com/) over stdio: **goose**, **codex** (via [codex-acp](https://github.com/zed-industries/codex-acp)), and **claude code** (via [claude-agent-acp](https://github.com/agentclientprotocol/claude-agent-acp)).
+Supports any agent that speaks [ACP](https://agentclientprotocol.com/) over stdio: **goose**, **codex** (via [codex-acp](https://github.com/zed-industries/codex-acp)), **claude code** (via [claude-agent-acp](https://github.com/agentclientprotocol/claude-agent-acp)), and **cursor** (native `agent acp` — no separate adapter).
 
 ## Prerequisites
 
@@ -91,6 +91,26 @@ buzz-acp
 Older installs that still expose `claude-code-acp` are also supported. `buzz-acp`
 treats both Claude ACP command names as the same zero-arg runtime.
 
+## Running with Cursor
+
+Cursor's Agent CLI speaks ACP natively — no separate `*-acp` adapter.
+
+```bash
+# Install: https://cursor.com/docs/cli (binary lands as `agent` / `cursor-agent`)
+agent login   # or export CURSOR_API_KEY=...
+
+export BUZZ_ACP_AGENT_COMMAND="agent"
+export BUZZ_ACP_AGENT_ARGS="acp"
+
+buzz-acp
+```
+
+> **Harness note:** Cursor ACP can emit blocking extension methods
+> (`cursor/ask_question`, `cursor/create_plan`). Headless `buzz-acp` needs an
+> explicit client policy for those (auto-allow vs reject-with-reason) so turns
+> neither hang nor over-permit. That policy is a separate design item from
+> registering the runtime in Desktop's `KNOWN_ACP_RUNTIMES`.
+
 ## Configuration
 
 All configuration is via environment variables (or CLI flags — every env var has a matching flag).

@@ -61,6 +61,7 @@ pub(crate) struct KnownAcpRuntime {
 const GOOSE_AVATAR_URL: &str = "https://goose-docs.ai/img/logo_dark.png";
 const CLAUDE_CODE_AVATAR_URL: &str = "https://anthropic.gallerycdn.vsassets.io/extensions/anthropic/claude-code/2.1.77/1773707456892/Microsoft.VisualStudio.Services.Icons.Default";
 const CODEX_AVATAR_URL: &str = "https://openai.gallerycdn.vsassets.io/extensions/openai/chatgpt/26.5313.41514/1773706730621/Microsoft.VisualStudio.Services.Icons.Default";
+pub(crate) const CURSOR_AVATAR_URL: &str = "https://www.cursor.com/favicon.ico";
 const BUZZ_AGENT_AVATAR_URL: &str =
     "https://raw.githubusercontent.com/block/buzz/refs/heads/main/crates/buzz-agent/buzz-agent.png";
 
@@ -153,10 +154,10 @@ const KNOWN_ACP_RUNTIMES: &[KnownAcpRuntime] = &[
         mcp_hooks: false,
         underlying_cli: Some("codex"),
         cli_install_commands: &["curl -fsSL https://chatgpt.com/codex/install.sh | sh"],
-        adapter_install_commands: &["npm install -g @zed-industries/codex-acp"],
+        adapter_install_commands: &["nix profile install --impure --file ~/buzz/nix/codex-acp-latest.nix"],
         install_instructions_url: "https://github.com/zed-industries/codex-acp",
         cli_install_hint: "Install the Codex CLI via the official install script.",
-        adapter_install_hint: "Install the Codex ACP adapter via npm.",
+        adapter_install_hint: "Install the latest Codex ACP adapter via the Buzz Nix package.",
         skill_dir: Some(".codex/skills"),
         supports_acp_model_switching: false,
         model_env_var: None,
@@ -171,6 +172,40 @@ const KNOWN_ACP_RUNTIMES: &[KnownAcpRuntime] = &[
         context_limit_env_var: None,
         required_normalized_fields: &[],
     },
+    // Cursor CLI speaks ACP natively (`agent acp`) — no separate *-acp adapter.
+    // Auth is `agent login` / CURSOR_API_KEY; see readiness probe.
+    // NOTE (sprout): Cursor ACP extension methods (cursor/ask_question,
+    // cursor/create_plan) are blocking client RPCs. Headless buzz-acp needs an
+    // explicit permission/policy decision so turns neither hang nor over-permit.
+    // That harness policy is intentionally NOT part of this registry entry.
+    KnownAcpRuntime {
+        id: "cursor",
+        label: "Cursor",
+        commands: &["agent", "cursor-agent"],
+        aliases: &["cursor"],
+        avatar_url: CURSOR_AVATAR_URL,
+        mcp_command: Some("buzz-dev-mcp"),
+        mcp_hooks: false,
+        underlying_cli: Some("agent"),
+        cli_install_commands: &["curl -fsSL https://cursor.com/install | bash"],
+        adapter_install_commands: &[],
+        install_instructions_url: "https://cursor.com/docs/cli/acp",
+        cli_install_hint: "Install the Cursor Agent CLI via the official install script.",
+        adapter_install_hint: "",
+        skill_dir: Some(".cursor/skills"),
+        supports_acp_model_switching: false,
+        model_env_var: None,
+        provider_env_var: None,
+        provider_locked: false,
+        default_env: &[],
+        config_file_path: Some("~/.cursor/cli-config.json"),
+        config_file_format: Some("json"),
+        supports_acp_native_config: false,
+        thinking_env_var: None,
+        max_tokens_env_var: None,
+        context_limit_env_var: None,
+        required_normalized_fields: &[],
+    },
     KnownAcpRuntime {
         id: "buzz-agent",
         label: "Buzz Agent",
@@ -470,7 +505,8 @@ pub fn create_time_agent_command_override(
 
 fn default_agent_args(command: &str) -> Option<Vec<String>> {
     match normalize_command_identity(command).as_str() {
-        "goose" => Some(vec!["acp".to_string()]),
+        // goose and Cursor both speak ACP as a subcommand (`goose acp`, `agent acp`).
+        "goose" | "agent" | "cursor-agent" | "cursor" => Some(vec!["acp".to_string()]),
         "codex" | "codex-acp" | "claude-agent-acp" | "claude-code-acp" | "claude-code"
         | "claudecode" | "buzz-agent" => Some(Vec::new()),
         _ => None,

@@ -5,7 +5,7 @@ use super::{
     divergent_agent_command_override, effective_agent_command, find_via_login_shell,
     managed_agent_avatar_url, normalize_agent_args, record_agent_command,
     update_time_agent_command_override, BUZZ_AGENT_AVATAR_URL, CLAUDE_CODE_AVATAR_URL,
-    CODEX_AVATAR_URL, GOOSE_AVATAR_URL,
+    CODEX_AVATAR_URL, CURSOR_AVATAR_URL, GOOSE_AVATAR_URL,
 };
 use crate::managed_agents::AcpAvailabilityStatus;
 
@@ -69,6 +69,48 @@ fn normalizes_claude_and_codex_args_to_empty() {
     );
 }
 
+#[test]
+fn normalizes_cursor_args_to_acp_subcommand() {
+    // Cursor speaks ACP natively as `agent acp` (same shape as goose).
+    assert_eq!(
+        normalize_agent_args("agent", Vec::new()),
+        vec!["acp".to_string()]
+    );
+    assert_eq!(
+        normalize_agent_args("cursor-agent", Vec::new()),
+        vec!["acp".to_string()]
+    );
+    assert_eq!(
+        normalize_agent_args("cursor", Vec::new()),
+        vec!["acp".to_string()]
+    );
+    // Explicit `acp` is preserved (default is already `["acp"]`).
+    assert_eq!(
+        normalize_agent_args("agent", vec!["acp".into()]),
+        vec!["acp".to_string()]
+    );
+}
+
+#[test]
+fn resolves_cursor_avatar() {
+    assert_eq!(
+        managed_agent_avatar_url("agent"),
+        Some(CURSOR_AVATAR_URL.to_string())
+    );
+    assert_eq!(
+        managed_agent_avatar_url("cursor-agent"),
+        Some(CURSOR_AVATAR_URL.to_string())
+    );
+    assert_eq!(
+        managed_agent_avatar_url("/Users/me/.local/bin/agent"),
+        Some(CURSOR_AVATAR_URL.to_string())
+    );
+    assert_eq!(
+        managed_agent_avatar_url("cursor"),
+        Some(CURSOR_AVATAR_URL.to_string())
+    );
+}
+
 #[test]
 fn resolves_buzz_agent_avatar() {
     assert_eq!(

@@ -210,6 +210,8 @@ impl AgentReadiness {
 /// * **claude**: a successful `claude auth status` probe.
 /// * **codex**: a successful `codex login status` probe (checks the codex
 ///   credential store — NOT `OPENAI_API_KEY`).
+/// * **cursor**: a successful `agent status` probe (Cursor CLI auth —
+///   `agent login` / `CURSOR_API_KEY`; native ACP, no separate adapter).
 /// * **unknown / custom command**: always `Ready` (no requirements known).
 ///
 /// Databricks note: `DATABRICKS_TOKEN` is `.unwrap_or_default()` in
@@ -252,6 +254,9 @@ fn collect_missing_requirements(
             rt,
         ),
         "codex" => cli_login_requirements(&["codex", "login", "status"], "run `codex login`", rt),
+        "cursor" => {
+            cli_login_requirements(&["agent", "status"], "run `agent login`", rt)
+        }
         _ => vec![],
     }
 }

@@ -38,6 +38,10 @@ pub(crate) const KNOWN_AGENT_BINARIES: &[&str] = &[
     "codex-acp",
     "codex_acp",
     "goose",
+    // Cursor Agent CLI (native ACP via `agent acp` / `cursor-agent acp`).
+    "agent",
+    "cursor-agent",
+    "cursor_agent",
     // buzz-dev-mcp's multicall personalities (rg, tree, buzz,
     // git-credential-nostr, git-sign-nostr) are short-lived per-tool-call
     // invocations — not listed here.

@@ -96,6 +96,20 @@ fn codex_has_mcp_command() {
     let p = known_acp_runtime("codex-acp").expect("should resolve");
     assert!(!p.mcp_hooks, "codex-acp does not handle MCP_HOOK_SERVERS");
     assert_eq!(p.mcp_command, Some("buzz-dev-mcp"));
+
+    let p = known_acp_runtime("agent").expect("cursor agent should resolve");
+    assert_eq!(p.id, "cursor");
+    assert!(!p.mcp_hooks, "cursor does not handle MCP_HOOK_SERVERS");
+    assert_eq!(p.skill_dir, Some(".cursor/skills"));
+    assert_eq!(p.mcp_command, Some("buzz-dev-mcp"));
+    assert!(
+        known_acp_runtime("cursor-agent").is_some_and(|r| r.id == "cursor"),
+        "cursor-agent alias should resolve"
+    );
+    assert!(
+        known_acp_runtime("cursor").is_some_and(|r| r.id == "cursor"),
+        "cursor id/alias should resolve"
+    );
 }
 
 #[test]