fix: check toolRequirements before ALWAYS_AVAILABLE_TOOLS

daniel-lxs · daniel-lxs · commit 975c425d385a · 2026-02-06T18:28:28.000-05:00
Moves the toolRequirements check before the ALWAYS_AVAILABLE_TOOLS
early-return in isToolAllowedForMode(). This ensures disabledTools
can block always-available tools (switch_mode, new_task, etc.) at
execution time, making the validation layer consistent with the
filtering layer.
diff --git a/src/core/tools/__tests__/validateToolUse.spec.ts b/src/core/tools/__tests__/validateToolUse.spec.ts
@@ -163,6 +163,15 @@ describe("mode-validator", () => {
 				// Even in code mode which allows all tools, disabled requirement should take precedence
 				expect(isToolAllowedForMode("apply_diff", codeMode, [], requirements)).toBe(false)
 			})
+
+			it("prioritizes requirements over ALWAYS_AVAILABLE_TOOLS", () => {
+				// Tools in ALWAYS_AVAILABLE_TOOLS (switch_mode, new_task, etc.) should still
+				// be blockable via toolRequirements / disabledTools
+				const requirements = { switch_mode: false, new_task: false, attempt_completion: false }
+				expect(isToolAllowedForMode("switch_mode", codeMode, [], requirements)).toBe(false)
+				expect(isToolAllowedForMode("new_task", codeMode, [], requirements)).toBe(false)
+				expect(isToolAllowedForMode("attempt_completion", codeMode, [], requirements)).toBe(false)
+			})
 		})
 	})
 
diff --git a/src/core/tools/validateToolUse.ts b/src/core/tools/validateToolUse.ts
@@ -126,7 +126,19 @@ export function isToolAllowedForMode(
 	experiments?: Record<string, boolean>,
 	includedTools?: string[], // Opt-in tools explicitly included (e.g., from modelInfo)
 ): boolean {
-	// Always allow these tools
+	// Check tool requirements first — explicit disabling takes priority over everything,
+	// including ALWAYS_AVAILABLE_TOOLS. This ensures disabledTools works consistently
+	// at both the filtering layer and the execution-time validation layer.
+	if (toolRequirements && typeof toolRequirements === "object") {
+		if (tool in toolRequirements && !toolRequirements[tool]) {
+			return false
+		}
+	} else if (toolRequirements === false) {
+		// If toolRequirements is a boolean false, all tools are disabled
+		return false
+	}
+
+	// Always allow these tools (unless explicitly disabled above)
 	if (ALWAYS_AVAILABLE_TOOLS.includes(tool as any)) {
 		return true
 	}
@@ -147,16 +159,6 @@ export function isToolAllowedForMode(
 		}
 	}
 
-	// Check tool requirements if any exist
-	if (toolRequirements && typeof toolRequirements === "object") {
-		if (tool in toolRequirements && !toolRequirements[tool]) {
-			return false
-		}
-	} else if (toolRequirements === false) {
-		// If toolRequirements is a boolean false, all tools are disabled
-		return false
-	}
-
 	const mode = getModeBySlug(modeSlug, customModes)
 
 	if (!mode) {
