diff --git a/CHANGELOG.md b/CHANGELOG.md
index a9aaa93a41..0d76c24431 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -27,6 +27,7 @@ Docs: https://docs.openclaw.ai
 - Discord: route autoThread replies to existing threads instead of the root channel. (#8302) Thanks @gavinbmoore, @thewilloftheshadow.
 - Discord/Agents: apply channel/group `historyLimit` during embedded-runner history compaction to prevent long-running channel sessions from bypassing truncation and overflowing context windows. (#11224) Thanks @shadril238.
 - Telegram: scope skill commands to the resolved agent for default accounts so `setMyCommands` no longer triggers `BOT_COMMANDS_TOO_MUCH` when multiple agents are configured. (#15599)
+- Plugins/Hooks: fire `before_tool_call` hook exactly once per tool invocation instead of twice when tools pass through both `wrapToolWithBeforeToolCallHook` and `toToolDefinitions`. (#15635) Thanks @lailoo.
 - Agents/Image tool: cap image-analysis completion `maxTokens` by model capability (`min(4096, model.maxTokens)`) to avoid over-limit provider failures while still preventing truncation. (#11770) Thanks @detecti1.
 - TUI/Streaming: preserve richer streamed assistant text when final payload drops pre-tool-call text blocks, while keeping non-empty final payload authoritative for plain-text updates. (#15452) Thanks @TsekaLuk.
 - Inbound/Web UI: preserve literal `\n` sequences when normalizing inbound text so Windows paths like `C:\\Work\\nxxx\\README.md` are not corrupted. (#11547) Thanks @mcaxtr.
diff --git a/src/agents/pi-tool-definition-adapter.after-tool-call.e2e.test.ts b/src/agents/pi-tool-definition-adapter.after-tool-call.e2e.test.ts
index 7e7c74a35e..8cfdade34c 100644
--- a/src/agents/pi-tool-definition-adapter.after-tool-call.e2e.test.ts
+++ b/src/agents/pi-tool-definition-adapter.after-tool-call.e2e.test.ts
@@ -35,10 +35,6 @@ describe("pi tool definition adapter after_tool_call", () => {
 
   it("dispatches after_tool_call once on successful adapter execution", async () => {
     hookMocks.runner.hasHooks.mockImplementation((name: string) => name === "after_tool_call");
-    hookMocks.runBeforeToolCallHook.mockResolvedValue({
-      blocked: false,
-      params: { mode: "safe" },
-    });
     const tool = {
       name: "read",
       label: "Read",
@@ -52,10 +48,13 @@ describe("pi tool definition adapter after_tool_call", () => {
 
     expect(result.details).toMatchObject({ ok: true });
     expect(hookMocks.runner.runAfterToolCall).toHaveBeenCalledTimes(1);
+    // after_tool_call receives the params as passed to toToolDefinitions;
+    // before_tool_call adjustment happens in wrapToolWithBeforeToolCallHook
+    // (upstream), not inside toToolDefinitions (#15502).
     expect(hookMocks.runner.runAfterToolCall).toHaveBeenCalledWith(
       {
         toolName: "read",
-        params: { mode: "safe" },
+        params: { path: "/tmp/file" },
         result,
       },
       { toolName: "read" },
diff --git a/src/agents/pi-tool-definition-adapter.ts b/src/agents/pi-tool-definition-adapter.ts
index 159b12cf3c..3d6cceedf7 100644
--- a/src/agents/pi-tool-definition-adapter.ts
+++ b/src/agents/pi-tool-definition-adapter.ts
@@ -91,17 +91,11 @@ export function toToolDefinitions(tools: AnyAgentTool[]): ToolDefinition[] {
       execute: async (...args: ToolExecuteArgs): Promise<AgentToolResult<unknown>> => {
         const { toolCallId, params, onUpdate, signal } = splitToolExecuteArgs(args);
         try {
-          // Call before_tool_call hook
-          const hookOutcome = await runBeforeToolCallHook({
-            toolName: name,
-            params,
-            toolCallId,
-          });
-          if (hookOutcome.blocked) {
-            throw new Error(hookOutcome.reason);
-          }
-          const adjustedParams = hookOutcome.params;
-          const result = await tool.execute(toolCallId, adjustedParams, signal, onUpdate);
+          // NOTE: before_tool_call hook is NOT called here — it is already
+          // invoked by wrapToolWithBeforeToolCallHook (applied in pi-tools.ts)
+          // before the tool reaches toToolDefinitions.  Calling it again would
+          // fire the hook twice per invocation (#15502).
+          const result = await tool.execute(toolCallId, params, signal, onUpdate);
 
           // Call after_tool_call hook
           const hookRunner = getGlobalHookRunner();
@@ -110,7 +104,7 @@ export function toToolDefinitions(tools: AnyAgentTool[]): ToolDefinition[] {
               await hookRunner.runAfterToolCall(
                 {
                   toolName: name,
-                  params: isPlainObject(adjustedParams) ? adjustedParams : {},
+                  params: isPlainObject(params) ? params : {},
                   result,
                 },
                 { toolName: name },
diff --git a/src/agents/pi-tools.before-tool-call.e2e.test.ts b/src/agents/pi-tools.before-tool-call.e2e.test.ts
index efc6c01104..f6a81bf1fc 100644
--- a/src/agents/pi-tools.before-tool-call.e2e.test.ts
+++ b/src/agents/pi-tools.before-tool-call.e2e.test.ts
@@ -1,6 +1,6 @@
 import { beforeEach, describe, expect, it, vi } from "vitest";
 import { getGlobalHookRunner } from "../plugins/hook-runner-global.js";
-import { toClientToolDefinitions } from "./pi-tool-definition-adapter.js";
+import { toClientToolDefinitions, toToolDefinitions } from "./pi-tool-definition-adapter.js";
 import { wrapToolWithBeforeToolCallHook } from "./pi-tools.before-tool-call.js";
 
 vi.mock("../plugins/hook-runner-global.js");
@@ -108,6 +108,44 @@ describe("before_tool_call hook integration", () => {
   });
 });
 
+describe("before_tool_call hook deduplication (#15502)", () => {
+  let hookRunner: {
+    hasHooks: ReturnType<typeof vi.fn>;
+    runBeforeToolCall: ReturnType<typeof vi.fn>;
+  };
+
+  beforeEach(() => {
+    hookRunner = {
+      hasHooks: vi.fn(() => true),
+      runBeforeToolCall: vi.fn(async () => undefined),
+    };
+    // oxlint-disable-next-line typescript/no-explicit-any
+    mockGetGlobalHookRunner.mockReturnValue(hookRunner as any);
+  });
+
+  it("fires hook exactly once when tool goes through wrap + toToolDefinitions", async () => {
+    const execute = vi.fn().mockResolvedValue({ content: [], details: { ok: true } });
+    // oxlint-disable-next-line typescript/no-explicit-any
+    const baseTool = { name: "web_fetch", execute, description: "fetch", parameters: {} } as any;
+
+    const wrapped = wrapToolWithBeforeToolCallHook(baseTool, {
+      agentId: "main",
+      sessionKey: "main",
+    });
+    const [def] = toToolDefinitions([wrapped]);
+
+    await def.execute(
+      "call-dedup",
+      { url: "https://example.com" },
+      undefined,
+      undefined,
+      undefined,
+    );
+
+    expect(hookRunner.runBeforeToolCall).toHaveBeenCalledTimes(1);
+  });
+});
+
 describe("before_tool_call hook integration for client tools", () => {
   let hookRunner: {
     hasHooks: ReturnType<typeof vi.fn>;