diff --git a/packages/coding-agent/CHANGELOG.md b/packages/coding-agent/CHANGELOG.md
index 0243ed841..ff32bd8db 100644
--- a/packages/coding-agent/CHANGELOG.md
+++ b/packages/coding-agent/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Fixed MCP tools hanging in non-yolo modes by declaring `approval = "write"` on `MCPTool` and `DeferredMCPTool`, and propagating the `approval` property through `customToolToDefinition()` in `sdk.ts`
+
 ## [15.10.1] - 2026-06-07
 
 ### Added
diff --git a/packages/coding-agent/src/extensibility/extensions/types.ts b/packages/coding-agent/src/extensibility/extensions/types.ts
index beeae8e39..17b78e334 100644
--- a/packages/coding-agent/src/extensibility/extensions/types.ts
+++ b/packages/coding-agent/src/extensibility/extensions/types.ts
@@ -7,7 +7,13 @@
  * - Register commands, keyboard shortcuts, and CLI flags
  * - Interact with the user via UI primitives
  */
-import type { AgentMessage, AgentToolResult, AgentToolUpdateCallback, ThinkingLevel } from "@oh-my-pi/pi-agent-core";
+import type {
+	AgentMessage,
+	AgentToolResult,
+	AgentToolUpdateCallback,
+	ThinkingLevel,
+	ToolApproval,
+} from "@oh-my-pi/pi-agent-core";
 import type { CompactionResult } from "@oh-my-pi/pi-agent-core/compaction";
 import type {
 	Api,
@@ -392,6 +398,9 @@ export interface ToolDefinition<TParams extends TSchema = TSchema, TDetails = un
 	defaultInactive?: boolean;
 	/** If true, tool may stage deferred changes that require explicit resolve/discard. */
 	deferrable?: boolean;
+	/** Tool approval tier. Defaults to `"exec"` when omitted.
+	 *  `"read"`: read-only operations. `"write"`: mutations. `"exec"`: code execution. */
+	approval?: ToolApproval;
 	/** MCP server name for discovery/search metadata when this tool fronts an MCP server. */
 	mcpServerName?: string;
 	/** Original MCP tool name for discovery/search metadata. */
diff --git a/packages/coding-agent/src/mcp/tool-bridge.ts b/packages/coding-agent/src/mcp/tool-bridge.ts
index 1b396ad4b..4063d8153 100644
--- a/packages/coding-agent/src/mcp/tool-bridge.ts
+++ b/packages/coding-agent/src/mcp/tool-bridge.ts
@@ -220,6 +220,7 @@ export class MCPTool implements CustomTool<TSchema, MCPToolDetails> {
 	readonly mcpToolName: string;
 	/** Server name */
 	readonly mcpServerName: string;
+	readonly approval = "write" as const;
 	/** Render completed MCP calls with the result header replacing the pending call header. */
 	readonly mergeCallAndResult = true;
 
@@ -305,6 +306,7 @@ export class DeferredMCPTool implements CustomTool<TSchema, MCPToolDetails> {
 	readonly mcpToolName: string;
 	/** Server name */
 	readonly mcpServerName: string;
+	readonly approval = "write" as const;
 	/** Render completed MCP calls with the result header replacing the pending call header. */
 	readonly mergeCallAndResult = true;
 
diff --git a/packages/coding-agent/src/sdk.ts b/packages/coding-agent/src/sdk.ts
index a28d834e5..748a8e651 100644
--- a/packages/coding-agent/src/sdk.ts
+++ b/packages/coding-agent/src/sdk.ts
@@ -709,6 +709,7 @@ function customToolToDefinition(tool: CustomTool): ToolDefinition {
 		parameters: tool.parameters,
 		hidden: tool.hidden,
 		deferrable: tool.deferrable,
+		approval: tool.approval,
 		mcpServerName: tool.mcpServerName,
 		mcpToolName: tool.mcpToolName,
 		execute: (toolCallId, params, signal, onUpdate, ctx) =>