fix(desktop): give Hermes scoped Buzz publication

crates/buzz-acp/README.md

@@ -267,9 +267,9 @@ Buzz Desktop supports registering any ACP-speaking agent tool as a selectable ru
 
 ### How it works
 
-**Tier-1 — compiled-in runtimes** (Goose, Claude Code, Codex, Buzz Agent): have auto-installers, auth probes, and first-class onboarding. Their IDs (`goose`, `claude`, `codex`, `buzz-agent`) are reserved and cannot be overridden.
+**Tier-1 — compiled-in runtimes** (Goose, Claude Code, Codex, Buzz Agent, Hermes Agent): have auth probes and first-class runtime metadata, including credential-scoped MCP publication where required. Their IDs (`goose`, `claude`, `codex`, `buzz-agent`, `hermes`) are reserved and cannot be overridden.
 
-**Tier-2 — preset catalog** (Cursor, Oh My Pi, Grok Build, OpenCode, Kimi Code, Amp, Hermes Agent, OpenClaw): static `HarnessDefinition` entries in `desktop/src-tauri/src/managed_agents/discovery.rs` (`PRESET_HARNESSES`). They are always present in the runtime catalog, PATH-probed for availability, not editable or deletable by the user. Displayed with bundled logos; if not installed, a docs link appears instead.
+**Tier-2 — preset catalog** (Cursor, Oh My Pi, Grok Build, OpenCode, Kimi Code, Amp, OpenClaw): static `HarnessDefinition` entries in `desktop/src-tauri/src/managed_agents/discovery.rs` (`PRESET_HARNESSES`). They are always present in the runtime catalog, PATH-probed for availability, not editable or deletable by the user. Displayed with bundled logos; if not installed, a docs link appears instead. Hermes Agent is tier 1 because Buzz must attach its credential-scoped MCP publication tool at spawn time.
 
 > **Note — OpenClaw:** `openclaw acp` is a Gateway-backed bridge; PATH availability shows "Available" even when the OpenClaw Gateway daemon is not running. This is expected tier-2 semantics (same class as a preset with unconfigured auth). The Gateway URL is configured via `OPENCLAW_GATEWAY_URL` (or the equivalent env var from OpenClaw's docs) — set it in the agent's **env vars** in Edit Agent, not in the definition env (the preset definition carries no env entries). Note that `openclaw acp` executes tools inside the Gateway daemon, not the Desktop process, so Desktop-injected `BUZZ_*` env vars do NOT reach the execution locus unless you also set them on the Gateway's own environment.
 

desktop/src-tauri/src/managed_agents/custom_harnesses.rs

@@ -216,11 +216,11 @@ pub(crate) fn validate_harness_definition_pub(def: &HarnessDefinition) -> Result
 /// collides with a built-in or preset is rejected to prevent shadowing (e.g. a
 /// file called `cursor.json` hiding the pre-existing tier-2 preset).
 ///
-/// Derived at compile time from `PRESET_HARNESSES` (tier-2) plus the four
+/// Derived at compile time from `PRESET_HARNESSES` (tier-2) plus the five
 /// tier-1 runtimes — no hand-maintained copy.  Adding a preset to
 /// `PRESET_HARNESSES` automatically reserves its ID without a separate edit.
 fn builtin_ids() -> impl Iterator<Item = &'static str> {
-    const TIER1: &[&str] = &["goose", "claude", "codex", "buzz-agent"];
+    const TIER1: &[&str] = &["goose", "claude", "codex", "buzz-agent", "hermes"];
     let tier2 = crate::managed_agents::discovery::preset_harness_ids();
     TIER1.iter().copied().chain(tier2.iter().copied())
 }

desktop/src-tauri/src/managed_agents/discovery.rs

@@ -9,14 +9,18 @@ use crate::managed_agents::{
     AcpAvailabilityStatus, AcpRuntimeCatalogEntry, AuthStatus, CommandAvailabilityInfo,
     HarnessSource,
 };
+mod args;
+mod hermes;
 mod presets;
 mod runtime_metadata;
 #[macro_use]
 mod windows_install;
+pub use args::normalize_agent_args;
 pub(crate) use presets::{
     canonical_harness_command, command_for_runtime_id, preset_harness_definitions,
     preset_harness_ids,
 };
+use hermes::HERMES_RUNTIME;
 use presets::{preset_catalog_entry, PRESET_HARNESSES};
 pub(crate) use runtime_metadata::KnownAcpRuntime;
 
@@ -211,6 +215,7 @@ const KNOWN_ACP_RUNTIMES: &[KnownAcpRuntime] = &[
         login_hint: None,
         auth_probe_args: None,
     },
+    HERMES_RUNTIME,
 ];
 
 /// Skill discovery directories declared by known runtimes.
@@ -440,38 +445,6 @@ pub fn try_record_agent_command(
     Ok(default_agent_command())
 }
 
-fn default_agent_args(command: &str) -> Option<Vec<String>> {
-    match normalize_command_identity(command).as_str() {
-        "goose" => Some(vec!["acp".to_string()]),
-        "codex" | "codex-acp" | "claude-agent-acp" | "claude-code-acp" | "claude-code"
-        | "claudecode" | "buzz-agent" => Some(Vec::new()),
-        _ => None,
-    }
-}
-
-pub fn normalize_agent_args(command: &str, agent_args: Vec<String>) -> Vec<String> {
-    let normalized = agent_args
-        .into_iter()
-        .map(|arg| arg.trim().to_string())
-        .filter(|arg| !arg.is_empty())
-        .collect::<Vec<_>>();
-
-    let Some(default_args) = default_agent_args(command) else {
-        return normalized;
-    };
-
-    if normalized.is_empty() {
-        return default_args;
-    }
-
-    if normalized.len() == 1 && normalized[0].eq_ignore_ascii_case("acp") && default_args.is_empty()
-    {
-        return default_args;
-    }
-
-    normalized
-}
-
 fn profile_target_dirs(root: &Path) -> [PathBuf; 2] {
     if cfg!(debug_assertions) {
         // `just dev` builds fresh debug sidecars; never prefer stale release output.

desktop/src-tauri/src/managed_agents/discovery/args.rs

@@ -0,0 +1,35 @@
+use super::normalize_command_identity;
+
+fn default_agent_args(command: &str) -> Option<Vec<String>> {
+    match normalize_command_identity(command).as_str() {
+        "goose" => Some(vec!["acp".to_string()]),
+        "codex" | "codex-acp" | "claude-agent-acp" | "claude-code-acp" | "claude-code"
+        | "claudecode" | "buzz-agent" | "hermes" | "hermes-acp" | "hermes-agent" => {
+            Some(Vec::new())
+        }
+        _ => None,
+    }
+}
+
+pub fn normalize_agent_args(command: &str, agent_args: Vec<String>) -> Vec<String> {
+    let normalized = agent_args
+        .into_iter()
+        .map(|arg| arg.trim().to_string())
+        .filter(|arg| !arg.is_empty())
+        .collect::<Vec<_>>();
+
+    let Some(default_args) = default_agent_args(command) else {
+        return normalized;
+    };
+
+    if normalized.is_empty() {
+        return default_args;
+    }
+
+    if normalized.len() == 1 && normalized[0].eq_ignore_ascii_case("acp") && default_args.is_empty()
+    {
+        return default_args;
+    }
+
+    normalized
+}

desktop/src-tauri/src/managed_agents/discovery/hermes.rs

@@ -0,0 +1,57 @@
+use super::KnownAcpRuntime;
+
+pub(super) const HERMES_RUNTIME: KnownAcpRuntime = KnownAcpRuntime {
+    id: "hermes",
+    label: "Hermes Agent",
+    commands: &["hermes-acp"],
+    aliases: &["hermes-agent"],
+    avatar_url: "",
+    // Hermes terminal subprocesses intentionally sanitize signing secrets.
+    // Give Hermes the credential-scoped Buzz MCP shell so message sends can
+    // emit recipient p-tags without exposing the key to generic tools.
+    mcp_command: Some("buzz-dev-mcp"),
+    mcp_hooks: true,
+    underlying_cli: Some("hermes"),
+    cli_install_commands: &[],
+    cli_install_commands_windows: &[],
+    adapter_install_commands: &[],
+    cli_install_instructions_url: "https://hermes-agent.nousresearch.com/docs",
+    adapter_install_instructions_url: "https://hermes-agent.nousresearch.com/docs",
+    cli_install_hint: "Install and configure Hermes Agent before using this runtime.",
+    adapter_install_hint: "Hermes Agent provides the hermes-acp adapter.",
+    skill_dir: Some(".hermes/skills"),
+    supports_acp_model_switching: true,
+    model_env_var: None,
+    provider_env_var: None,
+    provider_locked: false,
+    default_env: &[],
+    config_file_path: None,
+    config_file_format: None,
+    supports_acp_native_config: false,
+    thinking_env_var: None,
+    max_tokens_env_var: None,
+    context_limit_env_var: None,
+    max_rounds_env_var: None,
+    required_normalized_fields: &[],
+    login_hint: Some("Run `hermes setup` to configure a provider."),
+    auth_probe_args: None,
+};
+
+#[cfg(test)]
+mod tests {
+    use super::super::{known_acp_runtime, normalize_agent_args};
+
+    #[test]
+    fn runtime_uses_credential_scoped_buzz_mcp() {
+        let runtime = known_acp_runtime("/Users/test/.local/bin/hermes-acp")
+            .expect("hermes-acp should resolve as a known runtime");
+
+        assert_eq!(runtime.id, "hermes");
+        assert_eq!(runtime.mcp_command, Some("buzz-dev-mcp"));
+        assert!(runtime.mcp_hooks);
+        assert_eq!(
+            normalize_agent_args("hermes-acp", vec!["acp".into()]),
+            Vec::<String>::new()
+        );
+    }
+}

desktop/src-tauri/src/managed_agents/discovery/presets.rs

@@ -153,15 +153,6 @@ pub(super) const PRESET_HARNESSES: &[PresetHarness] = &[
         install_hint: "Buzz talks to the Amp CLI through the amp-acp adapter. Follow the setup guide to install the adapter so the amp-acp command is on your PATH.",
         underlying_cli: Some("amp"),
     },
-    PresetHarness {
-        id: "hermes",
-        label: "Hermes Agent",
-        command: "hermes-acp",
-        args: &[],
-        install_instructions_url: "https://hermes-agent.nousresearch.com",
-        install_hint: "Buzz talks to Hermes Agent through its hermes-acp command.",
-        underlying_cli: None,
-    },
     PresetHarness {
         id: "openclaw",
         label: "OpenClaw",