diff --git a/webui/src/web-components/sketch-tool-card-knowledge-base.ts b/webui/src/web-components/sketch-tool-card-knowledge-base.ts
new file mode 100644
index 0000000..48dd798
--- /dev/null
+++ b/webui/src/web-components/sketch-tool-card-knowledge-base.ts
@@ -0,0 +1,79 @@
+import { css, html, LitElement } from "lit";
+import { unsafeHTML } from "lit/directives/unsafe-html.js";
+import { customElement, property } from "lit/decorators.js";
+import { ToolCall } from "../types";
+import { marked } from "marked";
+
+// Safely renders markdown with fallback to plain text on failure
+function renderMarkdown(markdownContent: string): string {
+  try {
+    return marked.parse(markdownContent, {
+      gfm: true,
+      breaks: true,
+      async: false,
+    }) as string;
+  } catch (error) {
+    console.error("Error rendering markdown:", error);
+    return markdownContent;
+  }
+}
+
+@customElement("sketch-tool-card-knowledge-base")
+export class SketchToolCardKnowledgeBase extends LitElement {
+  @property() toolCall: ToolCall;
+  @property() open: boolean;
+
+  static styles = css`
+    .summary-text {
+      font-style: italic;
+    }
+    .knowledge-content {
+      background: rgb(246, 248, 250);
+      border-radius: 6px;
+      padding: 12px;
+      margin-top: 10px;
+      max-height: 300px;
+      overflow-y: auto;
+      border: 1px solid #e1e4e8;
+    }
+    .topic-label {
+      font-weight: bold;
+      color: #24292e;
+    }
+    .icon {
+      margin-right: 6px;
+    }
+  `;
+
+  render() {
+    const inputData = JSON.parse(this.toolCall?.input || "{}");
+    const topic = inputData.topic || "unknown";
+    const resultText = this.toolCall?.result_message?.tool_result || "";
+    
+    return html`
+      <sketch-tool-card .open=${this.open} .toolCall=${this.toolCall}>
+        <span slot="summary" class="summary-text">
+          <span class="icon">📚</span> Knowledge: ${topic}
+        </span>
+        <div slot="input">
+          <div>
+            <span class="topic-label">Topic:</span> ${topic}
+          </div>
+        </div>
+        ${this.toolCall?.result_message?.tool_result
+          ? html`<div slot="result">
+              <div class="knowledge-content">
+                ${unsafeHTML(renderMarkdown(resultText))}
+              </div>
+            </div>`
+          : ""}
+      </sketch-tool-card>
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "sketch-tool-card-knowledge-base": SketchToolCardKnowledgeBase;
+  }
+}