@@ -0,0 +1,104 @@
+// Reads an existing agent's deploy source back out of its workflow asset,
+// so the new-workbench picker can re-push the same definition into a
+// child tenant (agent-deploy.ts already generalizes that push+deploy).
+// There is no stock file-read route for a workflow asset (only
+// package-registry tarballs get one), so this fetches `main` over the
+// asset's smart-HTTP git remote with a short-lived read-only token.
+import { parseWorkflowSourceEntry, WORKFLOW_SOURCE_ENTRY_PATH } from "@corbits/workflows";
+import { type } from "arktype";
+
+import { fetchSourceFile } from "./git-fetch";
+
+export class AgentSourceReadError extends Error {}
+
+const GitTokenMintShape = type({ id: "string", secret: "string" });
+
+const AgentWorkflowJsonShape = type({
+  id: "string",
+  steps: type.Record(
+    "string",
+    type({
+      agent: type({
+        systemPrompt: "string",
+        inference: { sources: type({ provider: "string", model: "string" }).array() },
+      }),
+    }),
+  ),
+});
+
+const READ_TOKEN_LIFETIME_MS = 10 * 60 * 1000;
+
+async function readErrorBody(response: Response): Promise<string> {
+  const body: unknown = await response.json().catch(() => undefined);
+  const envelope = type({
+    error: { code: "string", userMessage: "string", refId: "string" },
+  })(body);
+  return envelope instanceof type.errors ? `HTTP ${response.status}` : envelope.error.userMessage;
+}
+
+/** An existing agent's deploy source, in the shape `deployAgentSource`'s
+ * `NewAgentInput` needs plus the sources it declares for inference. */
+export type AgentSource = {
+  readonly systemPrompt: string;
+  readonly declaredSources: readonly { readonly provider: string; readonly model: string }[];
+};
+
+/** Mints a read-only token, fetches the asset's `main`, and parses out the
+ * agent definition its source tree carries. */
+export async function readAgentSource(
+  tenantId: string,
+  assetId: string,
+  assetName: string,
+  fetchImpl: typeof fetch = fetch,
+): Promise<AgentSource> {
+  const tokensPath = `/api/tenants/${encodeURIComponent(tenantId)}/git-tokens`;
+  const minted = await fetchImpl(tokensPath, {
+    method: "POST",
+    headers: { "content-type": "application/json" },
+    body: JSON.stringify({
+      name: `agent-read-${crypto.randomUUID()}`,
+      resource: `asset:${assetId}`,
+      refPattern: "refs/heads/main",
+      actions: ["can_read"],
+      expiresAt: new Date(Date.now() + READ_TOKEN_LIFETIME_MS).toISOString(),
+    }),
+  });
+  if (!minted.ok) {
+    throw new AgentSourceReadError(`minting a read token failed: ${await readErrorBody(minted)}`);
+  }
+  const token = GitTokenMintShape(await minted.json());
+  if (token instanceof type.errors) {
+    throw new AgentSourceReadError(
+      `the read token came back an unexpected shape: ${token.summary}`,
+    );
+  }
+
+  const url = new URL(
+    `/api/tenants/${encodeURIComponent(tenantId)}/assets/workflow/${assetName}.git`,
+    globalThis.location.origin,
+  ).toString();
+  try {
+    const entryModule = await fetchSourceFile({
+      url,
+      token: token.secret,
+      filepath: WORKFLOW_SOURCE_ENTRY_PATH,
+    });
+    const workflowJson = parseWorkflowSourceEntry(entryModule, assetId);
+    const parsed = AgentWorkflowJsonShape(JSON.parse(workflowJson));
+    if (parsed instanceof type.errors) {
+      throw new AgentSourceReadError(
+        `this agent's source came back an unexpected shape: ${parsed.summary}`,
+      );
+    }
+    const step = Object.values(parsed.steps)[0];
+    if (step === undefined) {
+      throw new AgentSourceReadError("this agent's source has no steps to read a prompt from");
+    }
+    return {
+      systemPrompt: step.agent.systemPrompt,
+      declaredSources: step.agent.inference.sources,
+    };
+  } finally {
+    await fetchImpl(`${tokensPath}/${encodeURIComponent(token.id)}`, { method: "DELETE" });
+  }
+}
@@ -33,6 +33,9 @@ export type ChatAgent = {
    * redeploys, unlike a run id. */
   readonly id: string;
   readonly name: string;
+  /** The workflow asset's raw name — what its source is pushed at, e.g.
+   * for re-reading a deploy source; `name` above may be a display alias. */
+  readonly assetName: string;
   /** Every address this agent has ever run under, releases included. */
   readonly addresses: readonly string[];
   /** The address of the agent's currently live run, or null when none is
@@ -70,6 +73,11 @@ function displayAgentName(definitionName: string): string {
     : definitionName;
 }
 
+/** Myra is always in a new workbench and never a pickable option. */
+export function isMyraAgent(agent: Pick<ChatAgent, "assetName">): boolean {
+  return agent.assetName === MYRA_SOURCE_CONFIG.assetName;
+}
+
 export function agentInitials(name: string): string {
   const words = name.trim().split(/\s+/).filter(Boolean);
   const letters = words.slice(0, 2).map((word) => word[0] ?? "");
@@ -115,12 +123,16 @@ export async function listChatAgents(tenantId: string): Promise<readonly ChatAge
     byAsset.set(deployment.definitionAssetId, entry);
   }
 
-  return [...byAsset.entries()].map(([assetId, entry]) => ({
-    id: assetId,
-    name: displayAgentName(nameByAssetId.get(assetId) ?? assetId),
-    addresses: [...entry.addresses],
-    liveAddress: entry.liveAddress,
-  }));
+  return [...byAsset.entries()].map(([assetId, entry]) => {
+    const assetName = nameByAssetId.get(assetId) ?? assetId;
+    return {
+      id: assetId,
+      name: displayAgentName(assetName),
+      assetName,
+      addresses: [...entry.addresses],
+      liveAddress: entry.liveAddress,
+    };
+  });
 }
 
 /** The agent an `@name` first message picks, matched case-insensitively
 
@@ -0,0 +1,44 @@
+// Reads one file out of a hub asset repo from the browser, mirroring
+// `git-push.ts`'s in-memory clone but for the read side: isomorphic-git's
+// own upload-pack wire (unlike its receive-pack) parses the hub's
+// pkt-lines fine, so no hand-rolled wire code is needed here.
+import LightningFS from "@isomorphic-git/lightning-fs";
+import { Buffer } from "buffer";
+import git from "isomorphic-git";
+import http from "isomorphic-git/http/web";
+
+globalThis.Buffer ??= Buffer;
+
+export class GitFetchError extends Error {}
+
+const MAIN_REF = "refs/heads/main";
+
+/** Fetches `main` and returns `filepath`'s contents as text. */
+export async function fetchSourceFile(args: {
+  url: string;
+  token: string;
+  filepath: string;
+}): Promise<string> {
+  const fs = new LightningFS(`workbench-fetch-${crypto.randomUUID()}`, { wipe: true });
+  const dir = "/repo";
+  await fs.promises.mkdir(dir);
+  await git.init({ fs, dir, defaultBranch: "main" });
+  try {
+    await git.fetch({
+      fs,
+      http,
+      dir,
+      url: args.url,
+      ref: MAIN_REF,
+      singleBranch: true,
+      depth: 1,
+      tags: false,
+      headers: { Authorization: `Bearer ${args.token}` },
+    });
+    const oid = await git.resolveRef({ fs, dir, ref: "FETCH_HEAD" });
+    const { blob } = await git.readBlob({ fs, dir, oid, filepath: args.filepath });
+    return new TextDecoder().decode(blob);
+  } catch (cause) {
+    throw new GitFetchError(cause instanceof Error ? cause.message : String(cause));
+  }
+}
@@ -5,8 +5,9 @@
 import { Button, toast } from "@corbits/react-ui";
 import { PaperPlaneRight } from "@/lib/icons";
 import { CHAT_STRINGS, WorkbenchLoadingState } from "@/chat";
-import { useRef, useState } from "react";
-import { useMutation, useQueryClient } from "@tanstack/react-query";
+import { isMyraAgent, listChatAgents } from "@/chat/threads-api";
+import { useMemo, useRef, useState } from "react";
+import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
 import { reportError } from "@corbits/error-sink";
 
 import { useBench } from "../bench-context";
@@ -45,8 +46,25 @@ export function NewWorkbenchPickerRoute() {
   const queryClient = useQueryClient();
   const { selectedTenantId } = useBench();
   const [prompt, setPrompt] = useState("");
+  const [selectedAgentIds, setSelectedAgentIds] = useState<readonly string[]>([]);
   const promptRef = useRef<HTMLTextAreaElement | null>(null);
 
+  const agentsQuery = useQuery({
+    queryKey: ["bench-agents", selectedTenantId],
+    queryFn: () => listChatAgents(selectedTenantId!),
+    enabled: selectedTenantId !== null,
+  });
+  const pickableAgents = useMemo(
+    () => (agentsQuery.data ?? []).filter((agent) => !isMyraAgent(agent)),
+    [agentsQuery.data],
+  );
+
+  function toggleAgent(id: string) {
+    setSelectedAgentIds((current) =>
+      current.includes(id) ? current.filter((existing) => existing !== id) : [...current, id],
+    );
+  }
+
   const create = useMutation({
     mutationFn: ({
       benchTenantId,
@@ -59,6 +77,9 @@ export function NewWorkbenchPickerRoute() {
         benchTenantId,
         name: workbenchName(openingMessage ?? ""),
         ...(openingMessage !== undefined ? { openingMessage } : {}),
+        pickedAgents: pickableAgents
+          .filter((agent) => selectedAgentIds.includes(agent.id))
+          .map((agent) => ({ id: agent.id, name: agent.name, assetName: agent.assetName })),
       }),
     onSuccess: (tenantId, variables) => {
       void queryClient.invalidateQueries({
@@ -164,6 +185,22 @@ export function NewWorkbenchPickerRoute() {
               </div>
             </form>
 
+            {pickableAgents.length > 0 && (
+              <fieldset className="new-workbench-agent-picker">
+                <legend>Bring existing agents into this room</legend>
+                {pickableAgents.map((agent) => (
+                  <label key={agent.id} className="new-workbench-agent-option">
+                    <input
+                      type="checkbox"
+                      checked={selectedAgentIds.includes(agent.id)}
+                      onChange={() => toggleAgent(agent.id)}
+                    />
+                    {agent.name}
+                  </label>
+                ))}
+              </fieldset>
+            )}
+
             <button
               type="button"
               className="new-workbench-empty-channel"
 
@@ -5,6 +5,8 @@
 // resolved offering, which does inherit.
 
 import { listRoomParticipants, sendToRoom } from "@/chat/threads-api";
+import { deployAgentSource } from "./agent-deploy";
+import { readAgentSource } from "./agent-source-read";
 import { deployMyraSource } from "./myra-deploy";
 import { createFetchStockHub } from "./needs-converge";
 import { resolveExistingOffering } from "./onboarding/provider-connect-step";
@@ -39,6 +41,13 @@ export type CreateWorkbenchInput = {
   readonly benchTenantId: string;
   readonly name: string;
   readonly openingMessage?: string;
+  /** Existing bench agents to re-deploy into the room alongside Myra:
+   * their source asset id, name, and asset name (for reading it back). */
+  readonly pickedAgents?: readonly {
+    readonly id: string;
+    readonly name: string;
+    readonly assetName: string;
+  }[];
 };
 
 /** Returns the new room's tenant id — its deep link is `/w/<id>`. */
@@ -75,6 +84,17 @@ export async function createWorkbench(input: CreateWorkbenchInput): Promise<stri
       declaredSources: offering.declaredSources,
     });
     await hub.deployWorkflow(tenantId, deployInput);
+
+    // Each picked bench agent joins the room the same way Myra does: its
+    // source is read back out of the bench and re-pushed into the child,
+    // since a child's deploy rejects the parent's inherited asset outright.
+    for (const picked of input.pickedAgents ?? []) {
+      const source = await readAgentSource(input.benchTenantId, picked.id, picked.assetName);
+      await deployAgentSource({
+        tenantId,
+        input: { name: picked.name, systemPrompt: source.systemPrompt },
+      });
+    }
   } catch (cause) {
     throw failure(cause, "deploy");
   }