claude: pass --settings as a file path (avoid argv length limit)

hive-ag3nt/src/bin/hive-ag3nt.rs

@@ -127,6 +127,7 @@ async fn serve(
     tracing::info!(socket = %socket.display(), "hive-ag3nt serve");
     let _ = state; // reserved for future state transitions (turn-loop -> needs-login)
     let mcp_config = turn::write_mcp_config(socket).await?;
+    let settings = turn::write_settings(socket).await?;
     let label = std::env::var("HIVE_LABEL").unwrap_or_else(|_| "hive-ag3nt".into());
     let system_prompt = turn::write_system_prompt(socket, &label, mcp::Flavor::Agent).await?;
     loop {
@@ -143,6 +144,7 @@ async fn serve(
                     &prompt,
                     &mcp_config,
                     &system_prompt,
+                    &settings,
                     &bus,
                     mcp::Flavor::Agent,
                 )

hive-ag3nt/src/bin/hive-m1nd.rs

@@ -126,6 +126,7 @@ async fn one_shot(socket: &Path, req: ManagerRequest) -> Result<()> {
 async fn serve(socket: &Path, interval: Duration, bus: Bus) -> Result<()> {
     tracing::info!(socket = %socket.display(), "hive-m1nd serve");
     let mcp_config = turn::write_mcp_config(socket).await?;
+    let settings = turn::write_settings(socket).await?;
     let label = std::env::var("HIVE_LABEL").unwrap_or_else(|_| "hm1nd".into());
     let system_prompt = turn::write_system_prompt(socket, &label, mcp::Flavor::Manager).await?;
     loop {
@@ -159,6 +160,7 @@ async fn serve(socket: &Path, interval: Duration, bus: Bus) -> Result<()> {
                     &prompt,
                     &mcp_config,
                     &system_prompt,
+                    &settings,
                     &bus,
                     mcp::Flavor::Manager,
                 )

hive-ag3nt/src/turn.rs

@@ -51,6 +51,18 @@ pub async fn write_mcp_config(socket: &Path) -> Result<PathBuf> {
     Ok(path)
 }
 
+/// Drop the static `--settings` JSON next to the MCP config so we can
+/// pass a path (`--settings <file>`) instead of an ever-growing inline
+/// blob — the CLI argv has a finite length budget.
+pub async fn write_settings(socket: &Path) -> Result<PathBuf> {
+    let parent = socket.parent().unwrap_or_else(|| Path::new("/run/hive"));
+    tokio::fs::create_dir_all(parent).await.ok();
+    let path = parent.join("claude-settings.json");
+    tokio::fs::write(&path, CLAUDE_SETTINGS).await?;
+    tracing::info!(path = %path.display(), "wrote claude settings");
+    Ok(path)
+}
+
 /// Write the agent's / manager's static system prompt to a file next to
 /// the MCP config and return the path. Passed to claude via
 /// `--system-prompt-file`, replacing claude's default system prompt with
@@ -91,16 +103,17 @@ pub async fn drive_turn(
     prompt: &str,
     mcp_config: &Path,
     system_prompt: &Path,
+    settings: &Path,
     bus: &Bus,
     flavor: mcp::Flavor,
 ) -> TurnOutcome {
-    match run_turn(prompt, mcp_config, system_prompt, bus, flavor).await {
+    match run_turn(prompt, mcp_config, system_prompt, settings, bus, flavor).await {
         TurnOutcome::PromptTooLong => {
-            if let Err(e) = compact_session(bus).await {
+            if let Err(e) = compact_session(settings, bus).await {
                 tracing::warn!(error = %format!("{e:#}"), "compact failed");
                 return TurnOutcome::Failed(e);
             }
-            run_turn(prompt, mcp_config, system_prompt, bus, flavor).await
+            run_turn(prompt, mcp_config, system_prompt, settings, bus, flavor).await
         }
         other => other,
     }
@@ -157,6 +170,7 @@ pub async fn run_turn(
     prompt: &str,
     mcp_config: &Path,
     system_prompt: &Path,
+    settings: &Path,
     bus: &Bus,
     flavor: mcp::Flavor,
 ) -> TurnOutcome {
@@ -164,6 +178,7 @@ pub async fn run_turn(
         prompt,
         mcp_config,
         Some(system_prompt),
+        settings,
         bus,
         flavor,
         ClaudeMode::Turn,
@@ -179,7 +194,7 @@ pub async fn run_turn(
 /// Run claude's built-in `/compact` slash command on the persistent
 /// session so the next turn can fit. No MCP tools needed; we just feed
 /// `/compact` over stdin and let claude rewrite its own history.
-pub async fn compact_session(bus: &Bus) -> Result<()> {
+pub async fn compact_session(settings: &Path, bus: &Bus) -> Result<()> {
     bus.emit(LiveEvent::Note(
         "context overflow — running /compact on the persistent session".into(),
     ));
@@ -187,6 +202,7 @@ pub async fn compact_session(bus: &Bus) -> Result<()> {
         "/compact",
         Path::new("/dev/null"),
         None,
+        settings,
         bus,
         mcp::Flavor::Agent, // tool surface unused for /compact
         ClaudeMode::Compact,
@@ -206,6 +222,7 @@ async fn run_claude(
     prompt: &str,
     mcp_config: &Path,
     system_prompt: Option<&Path>,
+    settings: &Path,
     bus: &Bus,
     flavor: mcp::Flavor,
     mode: ClaudeMode,
@@ -219,7 +236,7 @@ async fn run_claude(
         .arg("haiku")
         .arg("--continue")
         .arg("--settings")
-        .arg(CLAUDE_SETTINGS);
+        .arg(settings);
     if let Some(p) = system_prompt {
         cmd.arg("--system-prompt-file").arg(p);
     }