(MOT-3873) feat(console): code mode picker

console/web/src/lib/backend/harness-send.ts

@@ -37,8 +37,12 @@ export type HarnessOutputContract =
   | { type: 'text' }
   | { type: 'json'; schema?: unknown }
 
-/** Operating mode — the harness prepends a short paragraph before the identity prompt. */
-export type HarnessSendMode = 'plan' | 'ask' | 'agent'
+/**
+ * Operating mode — the harness prepends a short paragraph before the identity
+ * prompt. `code` instead swaps in the coding identity and, when no explicit
+ * `functions` policy is sent, defaults to the native coding toolset.
+ */
+export type HarnessSendMode = 'plan' | 'ask' | 'agent' | 'code'
 
 /** Per-send options frozen onto the turn record. */
 export interface HarnessSendOptions {

console/web/src/lib/backend/real.ts

@@ -211,7 +211,9 @@ async function* realStream(
       session: { metadata: { surface: 'console' } },
       options: {
         mode,
-        functions: functionPolicy,
+        // Code mode omits `functions` so the harness applies its curated
+        // native coding policy; other modes keep the gate-configured surface.
+        ...(mode === 'code' ? {} : { functions: functionPolicy }),
         ...(thinkingLevel ? { thinking_level: thinkingLevel } : {}),
         metadata: buildTurnMetadata(sessionId, messageId, opts?.workingDir),
       },

console/web/src/types/chat.ts

@@ -1,4 +1,4 @@
-export type Mode = 'plan' | 'ask' | 'agent'
+export type Mode = 'plan' | 'ask' | 'agent' | 'code'
 
 /** Composite `provider::<catalog_model_id>` (matches harness models-catalog). */
 export const CATALOG_MODEL_KEY_SEP = '::' as const
@@ -15,6 +15,7 @@ export const MODES: { id: Mode; label: string }[] = [
   { id: 'plan', label: 'plan' },
   { id: 'ask', label: 'ask' },
   { id: 'agent', label: 'agent' },
+  { id: 'code', label: 'code' },
 ]
 
 export const DEFAULT_MODE: Mode = 'agent'

harness/prompts/code.txt

@@ -4,7 +4,7 @@ Your tools are attached natively to this conversation: file operations (the code
 
 # Workspace
 
-An <environment> block in this prompt describes your workspace: the working directory (all relative paths resolve there), the platform, the git state, and any repo instruction files (AGENTS.md / CLAUDE.md). Treat repo instruction files as authoritative conventions for this codebase — follow them even when they conflict with your defaults. Paths outside the workspace jail are rejected; stay inside it.
+An <environment> block in this prompt describes your workspace: the working directory (all relative paths resolve there), the platform, the git state, and any repo instruction files (AGENTS.md / CLAUDE.md). It is refreshed at the start of every turn — do not call coder::context to re-fetch what it already tells you; call it only when you have changed the git state mid-turn and need a fresh snapshot. Treat repo instruction files as authoritative conventions for this codebase — follow them even when they conflict with your defaults. Paths outside the workspace jail are rejected; stay inside it.
 
 # Working on code
 

shell/src/code/functions/context.rs

@@ -44,8 +44,10 @@ fn example_context_input() -> serde_json::Value {
 
 #[derive(Debug, Serialize, JsonSchema)]
 pub struct ContextOutput {
-    /// The primary allowed root — relative paths in every `coder::*` call
-    /// resolve against this directory.
+    /// The effective root for this call — the session's working directory
+    /// when the call carries a filesystem scope, else the primary allowed
+    /// root. Relative paths in `coder::*` calls resolve against it, and the
+    /// git state and instruction files below describe it.
     pub primary_root: String,
     /// Canonical absolute paths of all allowed roots, primary first.
     pub base_paths: Vec<String>,
@@ -93,15 +95,25 @@ pub struct InstructionFile {
 pub async fn handle(
     resolver: Arc<PathResolver>,
     _cfg: Arc<CoderConfig>,
-    _req: ContextInput,
+    req: ContextInput,
 ) -> Result<ContextOutput, String> {
-    let primary = resolver.base_root().to_path_buf();
+    // The effective root is the call's fs_scope root when the harness
+    // stamped one (the turn's working directory) — the configured primary
+    // only when the call is unscoped. session_root canonicalizes and
+    // confines it to the allowed roots, exactly like resolve_in.
+    let scope_root = crate::fs::scope_root(req.fs_scope.as_ref()).map(str::to_string);
+    let primary = scope_root
+        .as_deref()
+        .and_then(|r| resolver.session_root(r))
+        .unwrap_or_else(|| resolver.base_root().to_path_buf());
     let git = git_context(&primary).await;
     let resolver_for_files = resolver.clone();
-    let instruction_files =
-        tokio::task::spawn_blocking(move || read_instruction_files(&resolver_for_files))
-            .await
-            .map_err(|e| format!("context task join failed: {e}"))?;
+    let files_scope = scope_root.clone();
+    let instruction_files = tokio::task::spawn_blocking(move || {
+        read_instruction_files(&resolver_for_files, files_scope.as_deref())
+    })
+    .await
+    .map_err(|e| format!("context task join failed: {e}"))?;
 
     Ok(ContextOutput {
         primary_root: primary.display().to_string(),
@@ -164,11 +176,15 @@ async fn git_context(root: &Path) -> Option<GitContext> {
     })
 }
 
-fn read_instruction_files(resolver: &PathResolver) -> Vec<InstructionFile> {
+fn read_instruction_files(
+    resolver: &PathResolver,
+    scope_root: Option<&str>,
+) -> Vec<InstructionFile> {
     let mut out = Vec::new();
     for name in INSTRUCTION_FILE_NAMES {
-        // Resolve through the jail so non-accessible globs keep applying.
-        let Ok(abs) = resolver.resolve(name) else {
+        // Resolve through the jail (relative to the effective root) so
+        // non-accessible globs keep applying.
+        let Ok(abs) = resolver.resolve_opt(scope_root, name) else {
             continue;
         };
         if resolver.is_non_accessible(&abs) {

shell/tests/code_context.rs

@@ -87,3 +87,45 @@ async fn context_caps_oversized_instruction_file() {
     assert!(out.instruction_files[0].truncated);
     assert_eq!(out.instruction_files[0].content.len(), 16 * 1024);
 }
+
+#[tokio::test]
+async fn context_honors_fs_scope_root() {
+    let tmp = tempdir().unwrap();
+    let jail = tmp.path();
+    let proj = jail.join("proj");
+    std::fs::create_dir(&proj).unwrap();
+    git(&proj, &["init", "-b", "work"]);
+    std::fs::write(proj.join("AGENTS.md"), "scoped conventions\n").unwrap();
+    git(&proj, &["add", "."]);
+    git(&proj, &["commit", "-m", "scoped seed"]);
+
+    let (r, c) = make(jail.to_path_buf());
+    // Mirror the registration path: the harness stamps fs_scope and the
+    // wrapper widens the resolver with session_scoped before handling.
+    let scope = proj.to_string_lossy().to_string();
+    let scoped = r.session_scoped(Some(&scope), None);
+    let out = context_handle(
+        scoped,
+        c,
+        ContextInput {
+            fs_scope: Some(shell::fs::FsScope {
+                root: scope,
+                grants: vec![],
+            }),
+        },
+    )
+    .await
+    .unwrap();
+
+    assert!(
+        out.primary_root.ends_with("/proj"),
+        "effective root is the fs_scope root, got {}",
+        out.primary_root
+    );
+    let git_ctx = out.git.expect("scoped root is a git repo");
+    assert_eq!(git_ctx.branch, "work");
+    assert_eq!(out.instruction_files.len(), 1);
+    assert!(out.instruction_files[0]
+        .content
+        .contains("scoped conventions"));
+}

shell/tests/golden/schemas/coder.context.json

@@ -116,7 +116,7 @@
         "$ref": "#/definitions/Platform"
       },
       "primary_root": {
-        "description": "The primary allowed root — relative paths in every `coder::*` call resolve against this directory.",
+        "description": "The effective root for this call — the session's working directory when the call carries a filesystem scope, else the primary allowed root. Relative paths in `coder::*` calls resolve against it, and the git state and instruction files below describe it.",
         "type": "string"
       }
     },