feat(chat): support Harness Engine clients

README.md

@@ -284,6 +284,13 @@ caipe skills list
 caipe skills install <name>
 ```
 
+Agent listings, the interactive picker, and the chat footer show the selected
+execution harness (LangChain Deep Agents, AgentCore, Claude Agent SDK, or a
+custom harness). Harness Engine streams are detached from the CLI connection:
+if SSE disconnects, the CLI resumes the existing run from its last event ID
+without submitting the prompt or repeating provider/tool execution. Older
+CAIPE servers remain supported and default to LangChain Deep Agents metadata.
+
 ### Headless / CI
 
 ```bash

src/agents/AgentPicker.tsx

@@ -8,7 +8,7 @@ import type React from "react";
 import { PICKER_HINT_NAV } from "../chat/shortcuts.js";
 import { isRichTerminalEnabled } from "../platform/terminal/capabilities.js";
 import { pickerWindow, truncateText } from "./picker.js";
-import type { Agent } from "./types.js";
+import { type Agent, harnessDisplayName } from "./types.js";
 
 const DESC_SELECTED_MAX = 240;
 const ROW_SEPARATOR = "  ────────────────────────────────────────────────────────";
@@ -114,6 +114,13 @@ export function AgentPicker({
                     {" · in session"}
                   </Text>
                 ) : null}
+                <Text
+                  backgroundColor={rowBg}
+                  color={selected ? (rich ? "white" : "cyan") : undefined}
+                  dimColor={!selected}
+                >
+                  {` · ${harnessDisplayName(agent)}`}
+                </Text>
               </Box>
               {selected && descLine ? (
                 <>
@@ -152,6 +159,7 @@ export function AgentPicker({
         <Text bold color="white">
           {selectedAgent ? agentTitle(selectedAgent) : ""}
         </Text>
+        <Text dimColor>{selectedAgent ? ` · ${harnessDisplayName(selectedAgent)}` : ""}</Text>
         <Text dimColor>{` · Enter switch · ${agents.length} total · or /agents <id>`}</Text>
       </Box>
     </Box>

src/agents/List.tsx

@@ -5,7 +5,7 @@
 import { Box, Text } from "ink";
 import type React from "react";
 import { statusDot } from "../platform/display.js";
-import type { Agent } from "./types.js";
+import { type Agent, harnessDisplayName } from "./types.js";
 
 interface AgentListProps {
   agents: Agent[];
@@ -31,21 +31,25 @@ export function AgentList({ agents }: AgentListProps): React.ReactElement {
           {"Domain".padEnd(14)}
         </Text>
         <Text bold color="cyan">
-          {"Protocols".padEnd(16)}
+          {"Harness".padEnd(28)}
+        </Text>
+        <Text bold color="cyan">
+          {"Protocols".padEnd(12)}
         </Text>
         <Text bold color="cyan">
           Status
         </Text>
       </Box>
       <Box>
-        <Text dimColor>{"─".repeat(60)}</Text>
+        <Text dimColor>{"─".repeat(90)}</Text>
       </Box>
 
       {agents.map((agent) => (
         <Box key={agent.name}>
           <Text>{agent.name.padEnd(20)}</Text>
           <Text dimColor>{agent.domain.padEnd(14)}</Text>
-          <Text dimColor>{(agent.protocols ?? ["agui"]).join(", ").padEnd(16)}</Text>
+          <Text dimColor>{harnessDisplayName(agent).padEnd(28)}</Text>
+          <Text dimColor>{(agent.protocols ?? ["agui"]).join(", ").padEnd(12)}</Text>
           <Text>{statusDot(agent.available)}</Text>
           <Text dimColor> {agent.displayName}</Text>
         </Box>

src/agents/commands.ts

@@ -8,6 +8,7 @@ import { getValidToken } from "../auth/tokens.js";
 import { getAuthUrl, getServerUrl } from "../platform/config.js";
 import { AgentList } from "./List.js";
 import { fetchAgents, getAgent } from "./registry.js";
+import { harnessDisplayName, normalizeHarnessId } from "./types.js";
 
 interface GlobalOpts {
   url?: string;
@@ -31,6 +32,8 @@ export async function runAgentsList(
           name: a.name,
           displayName: a.displayName,
           domain: a.domain,
+          harnessId: normalizeHarnessId(a.harnessId),
+          harnessName: harnessDisplayName(a),
           protocols: a.protocols,
           available: a.available,
         })),
@@ -45,7 +48,7 @@ export async function runAgentsList(
     for (const a of agents) {
       const dot = a.available ? "✓" : "✗";
       process.stdout.write(
-        `${dot} ${a.name.padEnd(20)} ${a.domain.padEnd(12)} ${(a.protocols ?? ["agui"]).join(",")}\n`,
+        `${dot} ${a.name.padEnd(20)} ${a.domain.padEnd(12)} ${harnessDisplayName(a).padEnd(28)} ${(a.protocols ?? ["agui"]).join(",")}\n`,
       );
     }
     return;
@@ -68,6 +71,9 @@ export async function runAgentsInfo(name: string, globalOpts: GlobalOpts): Promi
   process.stdout.write(`\nAgent: ${agent.displayName}\n`);
   process.stdout.write(`  Name:        ${agent.name}\n`);
   process.stdout.write(`  Domain:      ${agent.domain}\n`);
+  process.stdout.write(
+    `  Harness:     ${harnessDisplayName(agent)} (${normalizeHarnessId(agent.harnessId)})\n`,
+  );
   process.stdout.write(`  Protocols:   ${(agent.protocols ?? ["agui"]).join(", ")}\n`);
   process.stdout.write(`  Available:   ${agent.available ? "yes" : "no"}\n`);
   process.stdout.write(`  Endpoint:    ${agent.endpoint}\n`);

src/agents/picker.ts

@@ -1,5 +1,6 @@
 import { pickerWindow } from "../chat/picker-nav.js";
 import type { Agent } from "./types.js";
+import { harnessDisplayName, normalizeHarnessId } from "./types.js";
 
 export { pickerWindow };
 
@@ -10,7 +11,9 @@ export function filterAgents(agents: Agent[], query: string): Agent[] {
     (a) =>
       a.name.toLowerCase().includes(q) ||
       a.displayName.toLowerCase().includes(q) ||
-      a.description.toLowerCase().includes(q),
+      a.description.toLowerCase().includes(q) ||
+      normalizeHarnessId(a.harnessId).includes(q) ||
+      harnessDisplayName(a).toLowerCase().includes(q),
   );
 }
 

src/agents/registry.ts

@@ -28,6 +28,8 @@ interface AgentPickerEntry {
   id: string;
   name: string;
   description: string;
+  harness_id?: string;
+  harness_name?: string;
 }
 
 interface AgentPickerResponse {
@@ -74,6 +76,8 @@ export async function fetchAgents(
       protocols: ["agui"],
       available: true,
       domain: "general",
+      harnessId: e.harness_id,
+      harnessName: e.harness_name,
     }));
     writeCache(serverUrl, agents);
     return agents;

src/agents/types.ts

@@ -10,6 +10,38 @@ export interface Agent {
   protocols: "agui"[];
   available: boolean;
   domain: string;
+  /** Execution runtime selected by the agent blueprint. Absent on older CAIPE servers. */
+  harnessId?: string;
+  /** Human-readable runtime name supplied by the server. */
+  harnessName?: string;
+}
+
+export function normalizeHarnessId(value?: string): string {
+  const normalized = value?.trim().toLowerCase();
+  if (
+    !normalized ||
+    normalized === "dynamic_agents" ||
+    normalized === "langchain-deepagents" ||
+    normalized === "langchain_deepagents"
+  ) {
+    return "dynamic_agents";
+  }
+  return normalized;
+}
+
+export function harnessDisplayName(agent: Pick<Agent, "harnessId" | "harnessName">): string {
+  const explicit = agent.harnessName?.trim();
+  if (explicit) return explicit;
+  switch (normalizeHarnessId(agent.harnessId)) {
+    case "dynamic_agents":
+      return "LangChain Deep Agents";
+    case "agentcore":
+      return "Amazon Bedrock AgentCore";
+    case "claude_agent_sdk":
+      return "Claude Agent SDK";
+    default:
+      return normalizeHarnessId(agent.harnessId);
+  }
 }
 
 export const DEFAULT_AGENT: Agent = {
@@ -20,4 +52,6 @@ export const DEFAULT_AGENT: Agent = {
   protocols: ["agui"],
   available: true,
   domain: "general",
+  harnessId: "dynamic_agents",
+  harnessName: "LangChain Deep Agents",
 };

src/chat/Repl.tsx

@@ -17,6 +17,7 @@ import { AgentPicker } from "../agents/AgentPicker.js";
 import { filterAgents, sortAgentsForPicker } from "../agents/picker.js";
 import { fetchAgents, getAgent } from "../agents/registry.js";
 import type { Agent } from "../agents/types.js";
+import { harnessDisplayName } from "../agents/types.js";
 import { loginBrowser } from "../auth/oauth.js";
 import { getValidToken } from "../auth/tokens.js";
 import {
@@ -1035,7 +1036,9 @@ export function Repl({
       adapterRef.current = createAdapter(target, ep.streamStart, () => getValidToken(authUrl2));
       conversationIdRef.current = undefined;
       setCurrentAgent(target);
-      pushAssistantPlain(`Switched to agent ${target.displayName ?? target.name}.`);
+      pushAssistantPlain(
+        `Switched to agent ${target.displayName ?? target.name} · ${harnessDisplayName(target)}.`,
+      );
     },
     [serverUrl, pushAssistantPlain],
   );
@@ -1919,6 +1922,7 @@ export function Repl({
           {currentAgent.name !== "hello-world" && currentAgent.name !== "default"
             ? `${currentAgent.name} · `
             : ""}
+          {`${harnessDisplayName(currentAgent)} · `}
           {totalTokenDisplay > 0 ? `~${totalTokenDisplay} tokens · ` : ""}
           {serverHost ?? ""}
         </Text>