diff --git a/index.ts b/index.ts
index 868a770..b598be9 100644
--- a/index.ts
+++ b/index.ts
@@ -434,6 +434,85 @@ export default function register(api: OpenClawPluginApi) {
     { name: "tdai_memory_search" },
   );
 
+  api.registerTool(
+    {
+      name: "tdai_memory_write",
+      label: "Memory Write",
+      description:
+        "Write an explicit, user-confirmed entry into long-term memory. " +
+        "Use sparingly for durable facts, preferences, or instructions that should be remembered across sessions. " +
+        "Do not use for transient task progress or unverified guesses.",
+      parameters: {
+        type: "object",
+        properties: {
+          content: {
+            type: "string",
+            description: "The memory content to store",
+          },
+          type: {
+            type: "string",
+            enum: ["persona", "episodic", "instruction"],
+            description: "Memory type. Defaults to episodic.",
+          },
+          scene_name: {
+            type: "string",
+            description: "Optional scene/category name. Defaults to manual.",
+          },
+        },
+        required: ["content"],
+      },
+      async execute(_toolCallId: string, params: Record<string, unknown>) {
+        const startMs = Date.now();
+        const content = String(params.content ?? "");
+        const type = typeof params.type === "string" ? params.type : undefined;
+        const sceneName = typeof params.scene_name === "string" ? params.scene_name : undefined;
+
+        api.logger.debug?.(
+          `${TAG} [tool] tdai_memory_write called: ` +
+          `contentLen=${content.length}, type=${type ?? "(default)"}, scene=${sceneName ?? "(default)"}`,
+        );
+
+        try {
+          const result = await core.writeMemory({ content, type, sceneName });
+          const elapsedMs = Date.now() - startMs;
+          api.logger.debug?.(
+            `${TAG} [tool] tdai_memory_write completed (${elapsedMs}ms): id=${result.record.id}`,
+          );
+          report("tool_call", {
+            tool: "tdai_memory_write",
+            type: result.record.type,
+            sceneName: result.record.scene_name,
+            durationMs: elapsedMs,
+            success: true,
+          });
+          return {
+            content: [{ type: "text" as const, text: result.text }],
+            details: {
+              id: result.record.id,
+              type: result.record.type,
+              scene_name: result.record.scene_name,
+            },
+          };
+        } catch (err) {
+          const elapsedMs = Date.now() - startMs;
+          const errMsg = err instanceof Error ? err.message : String(err);
+          api.logger.error(`${TAG} [tool] tdai_memory_write failed (${elapsedMs}ms): ${errMsg}`);
+          report("tool_call", {
+            tool: "tdai_memory_write",
+            durationMs: elapsedMs,
+            success: false,
+            error: errMsg,
+          });
+          return {
+            content: [{ type: "text" as const, text: `Memory write failed: ${errMsg}` }],
+            details: { error: errMsg },
+          };
+        }
+      },
+    },
+    { name: "tdai_memory_write" },
+  );
+
   // tdai_conversation_search — Agent-callable L0 conversation search tool
   // TODO: implement hard per-turn call limit via before_tool_call hook + execute early-return (方案 D)
   api.registerTool(
diff --git a/src/core/tdai-core.ts b/src/core/tdai-core.ts
index 977d4a2..0d7362a 100644
--- a/src/core/tdai-core.ts
+++ b/src/core/tdai-core.ts
@@ -36,6 +36,7 @@ import { performAutoRecall } from "./hooks/auto-recall.js";
 import { performAutoCapture } from "./hooks/auto-capture.js";
 import { executeMemorySearch, formatSearchResponse } from "./tools/memory-search.js";
 import { executeConversationSearch, formatConversationSearchResponse } from "./tools/conversation-search.js";
+import { executeMemoryWrite, type MemoryWriteParams, type MemoryWriteResult } from "./tools/memory-write.js";
 import {
   initDataDirectories,
   initStores,
@@ -325,6 +326,25 @@ export class TdaiCore {
     };
   }
 
+  /**
+   * Explicitly write a long-term L1 memory.
+   *
+   * This supports agent/tool-initiated writes for contexts that cannot rely on
+   * L0 auto-capture. It stores a new record only; it deliberately does not
+   * update/merge existing records because that would bypass the L1 dedup prompt.
+   */
+  async writeMemory(params: MemoryWriteParams): Promise<MemoryWriteResult> {
+    await this.storeReady?.catch(() => {});
+
+    return executeMemoryWrite({
+      params,
+      dataDir: this.dataDir,
+      vectorStore: this.vectorStore,
+      embeddingService: this.embeddingService,
+      logger: this.logger,
+    });
+  }
+
   /**
    * Handle end-of-conversation for a single session.
    *
diff --git a/src/core/tools/memory-write.test.ts b/src/core/tools/memory-write.test.ts
new file mode 100644
index 0000000..9d9db63
--- /dev/null
+++ b/src/core/tools/memory-write.test.ts
@@ -0,0 +1,57 @@
+import fs from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
+import { afterEach, describe, expect, it } from "vitest";
+import { executeMemoryWrite } from "./memory-write.js";
+
+const tempDirs: string[] = [];
+
+describe("executeMemoryWrite", () => {
+  afterEach(async () => {
+    await Promise.all(tempDirs.splice(0).map((dir) => fs.rm(dir, { recursive: true, force: true })));
+  });
+
+  it("stores an explicit memory in the L1 JSONL schema", async () => {
+    const dataDir = await fs.mkdtemp(path.join(os.tmpdir(), "tdai-memory-write-"));
+    tempDirs.push(dataDir);
+
+    const result = await executeMemoryWrite({
+      dataDir,
+      params: {
+        content: "User prefers concise status updates.",
+        type: "instruction",
+        sceneName: "collaboration",
+        sessionKey: "subagent-session",
+      },
+    });
+
+    expect(result.record.content).toBe("User prefers concise status updates.");
+    expect(result.record.type).toBe("instruction");
+    expect(result.record.scene_name).toBe("collaboration");
+    expect(result.record.sessionKey).toBe("subagent-session");
+    expect(result.record.source_message_ids[0]).toMatch(/^manual:m_/);
+    expect(result.text).toContain(result.record.id);
+
+    const files = await fs.readdir(path.join(dataDir, "records"));
+    expect(files).toHaveLength(1);
+    const lines = (await fs.readFile(path.join(dataDir, "records", files[0]!), "utf-8")).trim().split("\n");
+    expect(lines).toHaveLength(1);
+    expect(JSON.parse(lines[0]!).id).toBe(result.record.id);
+  });
+
+  it("rejects empty content", async () => {
+    const dataDir = await fs.mkdtemp(path.join(os.tmpdir(), "tdai-memory-write-"));
+    tempDirs.push(dataDir);
+
+    await expect(executeMemoryWrite({ dataDir, params: { content: "   " } })).rejects.toThrow("content is required");
+  });
+
+  it("rejects invalid memory types", async () => {
+    const dataDir = await fs.mkdtemp(path.join(os.tmpdir(), "tdai-memory-write-"));
+    tempDirs.push(dataDir);
+
+    await expect(
+      executeMemoryWrite({ dataDir, params: { content: "Remember this.", type: "temporary" } }),
+    ).rejects.toThrow("Invalid memory type");
+  });
+});
diff --git a/src/core/tools/memory-write.ts b/src/core/tools/memory-write.ts
new file mode 100644
index 0000000..8838919
--- /dev/null
+++ b/src/core/tools/memory-write.ts
@@ -0,0 +1,117 @@
+/**
+ * tdai_memory_write tool: explicit long-term memory insertion.
+ *
+ * This is intentionally store-only. It does not update or merge existing
+ * memories, so direct writes cannot silently rewrite L1 records while bypassing
+ * the L1 extraction conflict-resolution prompt.
+ */
+
+import type { IMemoryStore } from "../store/types.js";
+import type { EmbeddingService } from "../store/embedding.js";
+import type { Logger } from "../types.js";
+import { generateMemoryId, writeMemory, type MemoryRecord, type MemoryType } from "../record/l1-writer.js";
+
+const VALID_TYPES: MemoryType[] = ["persona", "episodic", "instruction"];
+const DEFAULT_TYPE: MemoryType = "episodic";
+const DEFAULT_SCENE = "manual";
+const DEFAULT_PRIORITY = 50;
+const MAX_CONTENT_CHARS = 4000;
+const TAG = "[memory-tdai][tdai_memory_write]";
+
+export interface MemoryWriteParams {
+  content: string;
+  type?: string;
+  sceneName?: string;
+  sessionKey?: string;
+  sessionId?: string;
+}
+
+export interface MemoryWriteResult {
+  record: MemoryRecord;
+  text: string;
+}
+
+export async function executeMemoryWrite(opts: {
+  params: MemoryWriteParams;
+  dataDir: string;
+  vectorStore?: IMemoryStore;
+  embeddingService?: EmbeddingService;
+  logger?: Logger;
+}): Promise<MemoryWriteResult> {
+  const content = normalizeContent(opts.params.content);
+  const type = normalizeType(opts.params.type);
+  const sceneName = normalizeSceneName(opts.params.sceneName);
+  const sessionKey = normalizeSessionKey(opts.params.sessionKey);
+  const sessionId = opts.params.sessionId?.trim() ?? "";
+  const now = new Date().toISOString();
+  const recordId = generateMemoryId();
+
+  const record = await writeMemory({
+    memory: {
+      content,
+      type,
+      priority: DEFAULT_PRIORITY,
+      scene_name: sceneName,
+      source_message_ids: [`manual:${recordId}`],
+      metadata: {
+        source: "tdai_memory_write",
+        written_at: now,
+      },
+    },
+    decision: {
+      record_id: recordId,
+      action: "store",
+      target_ids: [],
+    },
+    baseDir: opts.dataDir,
+    sessionKey,
+    sessionId,
+    logger: opts.logger,
+    vectorStore: opts.vectorStore,
+    embeddingService: opts.embeddingService,
+  });
+
+  if (!record) {
+    throw new Error("Memory write returned no record");
+  }
+
+  opts.logger?.debug?.(
+    `${TAG} Stored memory id=${record.id} type=${record.type} scene=${record.scene_name} ` +
+    `sessionKey=${record.sessionKey} contentLen=${record.content.length}`,
+  );
+
+  return {
+    record,
+    text: `Memory written: ${record.id} (${record.type}, scene=${record.scene_name})`,
+  };
+}
+
+function normalizeContent(raw: string): string {
+  const content = String(raw ?? "").trim();
+  if (!content) {
+    throw new Error("content is required");
+  }
+  if (content.length > MAX_CONTENT_CHARS) {
+    throw new Error(`content is too long (max ${MAX_CONTENT_CHARS} characters)`);
+  }
+  return content;
+}
+
+function normalizeType(raw: string | undefined): MemoryType {
+  if (!raw) return DEFAULT_TYPE;
+  const normalized = raw.trim().toLowerCase();
+  if (VALID_TYPES.includes(normalized as MemoryType)) {
+    return normalized as MemoryType;
+  }
+  throw new Error(`Invalid memory type "${raw}". Expected one of: ${VALID_TYPES.join(", ")}`);
+}
+
+function normalizeSceneName(raw: string | undefined): string {
+  const sceneName = raw?.trim();
+  return sceneName || DEFAULT_SCENE;
+}
+
+function normalizeSessionKey(raw: string | undefined): string {
+  const sessionKey = raw?.trim();
+  return sessionKey || "manual-write";
+}