chore: release hub 0.0.7

.gitea/workflows/hub-check.yml

@@ -93,8 +93,8 @@ jobs:
 
       - name: Prove real Claude SDK Bash sandbox boundary
         run: |
-          sudo install -d -o "$(id -u)" -g "$(id -g)" -m 0700 /var/lib/cph-test
-          CPH_SANDBOX_TEST_ROOT=/var/lib/cph-test \
+          sudo install -d -o "$(id -u)" -g "$(id -g)" -m 0700 /w/t
+          CPH_SANDBOX_TEST_ROOT=/w/t \
             /usr/bin/setpriv --no-new-privs \
             npx vitest run test/integration/agent-sandbox-linux.test.ts
 

docs/adr/0018-agent-execution-surface-bounded-by-workspace.md

@@ -93,22 +93,26 @@ The boundary is enforced by the Claude Code SDK's built-in sandbox
   its Bash subprocesses run sandboxed; if the sandbox can't start, `query()`
   emits an error and exits rather than running unsandboxed.
 - `sandbox.allowUnsandboxedCommands: false` — a tool cannot opt out with the
-  SDK's `dangerouslyDisableSandbox` input.
+  SDK's `dangerouslyDisableSandbox` input. Claude Code 2.1.202 does not enforce
+  that option reliably, so a host-side `PreToolUse` hook also denies every
+  Bash request whose input explicitly sets `dangerouslyDisableSandbox: true`
+  before a process can start.
 - `sandbox.filesystem.denyRead: ["/"]` with `allowRead` for the canonical
   current workspace and a small named system-runtime set — normal reads stay
   in the run's workspace while `/bin`, shared libraries, CA certificates,
   fonts and the configured `cph` executable remain available as the external
   tool exception described above.
-- `sandbox.filesystem.allowWrite: [workspaceDir]` confines every write to the
-  canonical ADR-0007 workspace. Config/cache/home stay beneath
-  `.cph/agent-runtime/`. `TMPDIR`, `TMP`, and `TEMP` use the absolute
-  workspace-local `.cph/t/` path so tools remain anchored after `cd`;
-  `CLAUDE_CODE_TMPDIR` uses the short relative `.cph/t` prefix, resolved from
-  the canonical workspace cwd, because the SDK's socat bridge otherwise falls
-  back to a host temp directory when its Unix-socket prefix is too long.
-  Root is denied for writes and only the canonical workspace is re-opened, so
-  `/tmp`, `/var/tmp`, sibling projects and every other host path are rejected.
-  There is no writable scratch exception outside the project directory.
+- `sandbox.filesystem.allowWrite: [workspaceDir]` confines persistent host
+  effects to the canonical ADR-0007 workspace. Config/cache/home stay beneath
+  `.cph/agent-runtime/`; `TMPDIR`, `TMP`, `TEMP`, and `CLAUDE_CODE_TMPDIR` all
+  point at the workspace-local `.cph/t`. The workspace allocator uses stable
+  compact Organization/Project path segments, deployment requires a short
+  workspace root, and the canonical temp prefix fails fast above 56 bytes so
+  the SDK can append randomized `socat` bridge socket names without exceeding
+  Linux `sockaddr_un.sun_path`. Bubblewrap shadows non-allowlisted host trees
+  with disposable tmpfs mounts: a shell write there may succeed inside that
+  private namespace, but it cannot mutate the corresponding host path. The
+  Linux proof checks host state after the sandbox exits.
 - The SDK subprocess environment replaces rather than spreads `process.env`.
   Only provider protocol variables and non-secret runtime variables cross the
   boundary; database, Feishu and Hub session credentials never enter it.

docs/para-26071100-feishu-setup.md

@@ -23,7 +23,7 @@ Bot Open ID 不需要管理员手工寻找。平台部署人员会使用 App ID/
 - 获取消息内容，用于读取触发消息和线程上下文（`im:message:readonly`）
 - 获取与上传图片或文件资源（`im:resource`）
 - 添加、删除消息表情回复（`im:message.reactions:write_only`）
-- 获取用户基本信息（`contact:user.base:readonly`）
+- 获取用户基本信息（`contact:user.base:readonly`、`contact:user.basic_profile:readonly`）
 
 如果飞书 API 调试台提示某个上述操作缺少更细粒度权限，请把提示截图交给平台部署人员，不要直接勾选通讯录全量读取或其他超出清单的权限。
 

hub/deploy/README.md

@@ -15,6 +15,7 @@ Application code lives in immutable versioned directories under
 sudo BASE=/srv/curriculum-project-hub \
   HUB_DIR=/srv/curriculum-project-hub/releases/<release-id>/hub \
   INSTANCE_ID=org-a \
+  WORKSPACE_ROOT=/w/997 \
   PORT=8788 \
   MEMORY_MAX=16G CPU_QUOTA=400% TASKS_MAX=512 \
   bash /srv/curriculum-project-hub/releases/<release-id>/hub/deploy/install_service.sh
@@ -49,7 +50,7 @@ Default state paths are:
 ```text
 /var/lib/cph-hub/org-a/home
 /var/lib/cph-hub/org-a/state
-/var/lib/cph-hub/org-a/workspaces
+/w/997
 /var/cache/cph-hub/org-a
 ```
 

hub/deploy/deploy_platform.sh

@@ -10,6 +10,7 @@
 #   PLATFORM_DEPLOY_BASE     optional, defaults to /srv/curriculum-project-hub
 #   PLATFORM_DEPLOY_RELEASE  optional immutable release id, defaults to git HEAD
 #   PLATFORM_DEPLOY_INSTANCE required, Silo instance id
+#   PLATFORM_DEPLOY_WORKSPACE_ROOT required short per-Silo path (for example /w/997)
 #   PLATFORM_DEPLOY_MEMORY_MAX / CPU_QUOTA / TASKS_MAX required ceilings
 #   PLATFORM_DEPLOY_HEALTH_URL optional, defaults to http://127.0.0.1:8788/api/healthz
 # The target host must have Node.js 24+, npm, rsync, PostgreSQL client tools
@@ -31,6 +32,7 @@ REPO_ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)"
 RELEASE_ID="${PLATFORM_DEPLOY_RELEASE:-$(git -C "$REPO_ROOT" rev-parse --verify HEAD)}"
 [[ "$RELEASE_ID" =~ ^[A-Za-z0-9._-]+$ ]] || { echo "invalid PLATFORM_DEPLOY_RELEASE" >&2; exit 1; }
 INSTANCE_ID="${PLATFORM_DEPLOY_INSTANCE:?PLATFORM_DEPLOY_INSTANCE required}"
+WORKSPACE_ROOT="${PLATFORM_DEPLOY_WORKSPACE_ROOT:?PLATFORM_DEPLOY_WORKSPACE_ROOT required}"
 SERVICE_UNIT="cph-hub-$INSTANCE_ID.service"
 MEMORY_MAX="${PLATFORM_DEPLOY_MEMORY_MAX:?PLATFORM_DEPLOY_MEMORY_MAX required}"
 CPU_QUOTA="${PLATFORM_DEPLOY_CPU_QUOTA:?PLATFORM_DEPLOY_CPU_QUOTA required}"
@@ -67,11 +69,11 @@ fi
 ssh "${SSH_OPTS[@]}" "$DEPLOY_USER@$HOST" "
   set -euo pipefail
   if [ \"\$(id -u)\" = \"0\" ]; then
-    BASE='$BASE' HUB_DIR='$HUB_DIR' INSTANCE_ID='$INSTANCE_ID' PORT='$HUB_PORT' MEMORY_MAX='$MEMORY_MAX' CPU_QUOTA='$CPU_QUOTA' TASKS_MAX='$TASKS_MAX' bash '$HUB_DIR/deploy/install_service.sh'
+    BASE='$BASE' HUB_DIR='$HUB_DIR' INSTANCE_ID='$INSTANCE_ID' WORKSPACE_ROOT='$WORKSPACE_ROOT' PORT='$HUB_PORT' MEMORY_MAX='$MEMORY_MAX' CPU_QUOTA='$CPU_QUOTA' TASKS_MAX='$TASKS_MAX' bash '$HUB_DIR/deploy/install_service.sh'
     systemctl restart '$SERVICE_UNIT'
     systemctl is-active --quiet '$SERVICE_UNIT'
   else
-    sudo -n BASE='$BASE' HUB_DIR='$HUB_DIR' INSTANCE_ID='$INSTANCE_ID' PORT='$HUB_PORT' MEMORY_MAX='$MEMORY_MAX' CPU_QUOTA='$CPU_QUOTA' TASKS_MAX='$TASKS_MAX' bash '$HUB_DIR/deploy/install_service.sh'
+    sudo -n BASE='$BASE' HUB_DIR='$HUB_DIR' INSTANCE_ID='$INSTANCE_ID' WORKSPACE_ROOT='$WORKSPACE_ROOT' PORT='$HUB_PORT' MEMORY_MAX='$MEMORY_MAX' CPU_QUOTA='$CPU_QUOTA' TASKS_MAX='$TASKS_MAX' bash '$HUB_DIR/deploy/install_service.sh'
     sudo -n systemctl restart '$SERVICE_UNIT'
     sudo -n systemctl is-active --quiet '$SERVICE_UNIT'
   fi

hub/deploy/install_service.sh

@@ -23,7 +23,7 @@ SERVICE_GROUP="${SERVICE_GROUP:-$SERVICE_USER}"
 SERVICE_HOME="${SERVICE_HOME:-/var/lib/cph-hub/$INSTANCE_ID/home}"
 STATE_DIR="${STATE_DIR:-/var/lib/cph-hub/$INSTANCE_ID/state}"
 CACHE_DIR="${CACHE_DIR:-/var/cache/cph-hub/$INSTANCE_ID}"
-WORKSPACE_ROOT="${WORKSPACE_ROOT:-/var/lib/cph-hub/$INSTANCE_ID/workspaces}"
+WORKSPACE_ROOT="${WORKSPACE_ROOT:?WORKSPACE_ROOT required (use a short per-Silo path such as /w/997)}"
 HOST="${HOST:-127.0.0.1}"
 PORT="${PORT:?PORT is required and must be unique on the host}"
 ENV_FILE="${ENV_FILE:-$BASE/.secrets/$INSTANCE_ID/platform.env}"
@@ -120,6 +120,7 @@ done
 [[ "$MEMORY_MAX" =~ ^[1-9][0-9]*[KMGT]$ ]] || fail "MEMORY_MAX must be a systemd byte size such as 16G"
 [[ "$CPU_QUOTA" =~ ^[1-9][0-9]*%$ ]] || fail "CPU_QUOTA must be a positive percentage such as 400%"
 [[ "$TASKS_MAX" =~ ^[1-9][0-9]*$ ]] || fail "TASKS_MAX must be a positive integer"
+[ "${#WORKSPACE_ROOT}" -le 16 ] || fail "WORKSPACE_ROOT must be at most 16 bytes for Agent sandbox sockets: $WORKSPACE_ROOT"
 
 KEYRING_CREATED=false
 if [ -L "$KEYRING_FILE" ]; then

hub/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "@paradigm/hub",
-  "version": "0.0.4",
+  "version": "0.0.7",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@paradigm/hub",
-      "version": "0.0.4",
+      "version": "0.0.7",
       "dependencies": {
         "@anthropic-ai/claude-agent-sdk": "^0.3.202",
         "@fastify/cookie": "^11.0.2",

hub/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@paradigm/hub",
-  "version": "0.0.4",
+  "version": "0.0.7",
   "private": true,
   "type": "module",
   "engines": {

hub/src/agent/runner.ts

@@ -29,7 +29,7 @@
  * `workspace.ts` `confine()` path validator as a tool wrapper — the OS sandbox
  * is the mechanism, the contract pins the invariant.
  */
-import { query, type McpServerConfig, type SDKMessage, type SDKAssistantMessage, type SDKUserMessage, type SDKResultMessage, type SDKPartialAssistantMessage } from "@anthropic-ai/claude-agent-sdk";
+import { query, type HookCallback, type McpServerConfig, type SDKMessage, type SDKAssistantMessage, type SDKUserMessage, type SDKResultMessage, type SDKPartialAssistantMessage } from "@anthropic-ai/claude-agent-sdk";
 import type { PrismaClient } from "@prisma/client";
 import { claudeSdkToolConfigForRole } from "./roleTools.js";
 import { createAgentSecurityPolicy } from "./security.js";
@@ -96,6 +96,22 @@ export interface RunResult {
 
 const DEFAULT_MAX_TURNS = 25;
 
+const denyUnsandboxedBash: HookCallback = async (input) => {
+  if (input.hook_event_name !== "PreToolUse" || input.tool_name !== "Bash") return {};
+  const toolInput = input.tool_input;
+  if (
+    typeof toolInput !== "object" || toolInput === null ||
+    !("dangerouslyDisableSandbox" in toolInput) || toolInput.dangerouslyDisableSandbox !== true
+  ) return {};
+  return {
+    hookSpecificOutput: {
+      hookEventName: "PreToolUse",
+      permissionDecision: "deny",
+      permissionDecisionReason: "This deployment requires every Bash command to remain sandboxed.",
+    },
+  };
+};
+
 export async function runAgent(req: RunRequest): Promise<RunResult> {
   const onStream = req.onStream;
   const cap = req.maxTurns ?? DEFAULT_MAX_TURNS;
@@ -151,6 +167,12 @@ export async function runAgent(req: RunRequest): Promise<RunResult> {
       // settings that could widen tools, hooks, MCP servers, or sandbox paths.
       settingSources: [],
       strictMcpConfig: true,
+      // Claude Code 2.1.202 can honor the per-call opt-out despite
+      // sandbox.allowUnsandboxedCommands=false. Enforce the invariant again at
+      // the PreToolUse boundary, before the Bash process can be spawned.
+      hooks: {
+        PreToolUse: [{ matcher: "Bash", hooks: [denyUnsandboxedBash] }],
+      },
     };
     if (req.systemPrompt !== undefined) options.systemPrompt = req.systemPrompt;
     if (req.model !== undefined) options.model = req.model;

hub/src/agent/security.ts

@@ -26,6 +26,11 @@ const SANDBOX_HIDDEN_ENV_KEYS = [
   "ANTHROPIC_API_KEY",
 ] as const;
 
+// Linux sockaddr_un.sun_path is 108 bytes including the terminator. Claude's
+// sandbox appends its own user directory and randomized bridge socket names,
+// so keep our prefix well below that hard limit.
+const MAX_AGENT_TMP_PREFIX_BYTES = 56;
+
 export interface AgentSecurityInput {
   readonly workspaceRoot: string;
   readonly workspaceDir: string;
@@ -72,10 +77,8 @@ export async function createAgentSecurityPolicy(input: AgentSecurityInput): Prom
   const agentCache = await ensureDirectoryTree(runtimeRoot, ["cache"]);
   const agentConfig = await ensureDirectoryTree(runtimeRoot, ["config"]);
   const agentState = await ensureDirectoryTree(runtimeRoot, ["state"]);
-  // Keep the SDK temp root both short enough for Linux AF_UNIX sockets and
-  // physically inside the project boundary pinned by AgentFileOp.Authorized.
   const agentTmp = await ensureDirectoryTree(cphRoot, ["t"]);
-  const claudeCodeTmp = join(".cph", "t");
+  assertShortAgentTemp(agentTmp);
 
   const path = hostEnv["PATH"]?.trim();
   if (path === undefined || path === "") {
@@ -91,14 +94,13 @@ export async function createAgentSecurityPolicy(input: AgentSecurityInput): Prom
   env.XDG_CACHE_HOME = agentCache;
   env.XDG_CONFIG_HOME = agentConfig;
   env.XDG_STATE_HOME = agentState;
-  // General subprocess temp paths stay absolute so tools continue to work
-  // after `cd`. Only the SDK's socket prefix is relative: Claude resolves it
-  // from the canonical workspace cwd before Bash commands can change cwd.
+  // All four variables must use the short path. Claude's sandbox bridge uses
+  // the ordinary temp variables, while other SDK paths use CLAUDE_CODE_TMPDIR.
   env.TMPDIR = agentTmp;
   env.TMP = agentTmp;
   env.TEMP = agentTmp;
   env.CLAUDE_CONFIG_DIR = agentConfig;
-  env.CLAUDE_CODE_TMPDIR = claudeCodeTmp;
+  env.CLAUDE_CODE_TMPDIR = agentTmp;
   env.CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC = "1";
   env.DISABLE_TELEMETRY = "1";
   env.DO_NOT_TRACK = "1";
@@ -142,6 +144,15 @@ export async function createAgentSecurityPolicy(input: AgentSecurityInput): Prom
   };
 }
 
+function assertShortAgentTemp(agentTmp: string): void {
+  const prefixBytes = Buffer.byteLength(agentTmp);
+  if (prefixBytes > MAX_AGENT_TMP_PREFIX_BYTES) {
+    throw new Error(
+      `Agent temp path is too long for sandbox bridge sockets (${prefixBytes} > ${MAX_AGENT_TMP_PREFIX_BYTES} bytes): ${agentTmp}`,
+    );
+  }
+}
+
 function hostRuntimeReadPaths(env: Readonly<Record<string, string | undefined>>): string[] {
   const platformPaths = process.platform === "darwin"
     ? [
@@ -282,7 +293,7 @@ async function ensureDirectoryTree(root: string, components: readonly string[]):
   }
   const canonical = await realpath(current);
   if (canonical !== current || !isStrictDescendant(root, canonical)) {
-    throw new Error(`Agent runtime path escapes project workspace: ${current}`);
+    throw new Error(`Agent runtime path escapes its configured root: ${current}`);
   }
   await chmod(canonical, 0o700);
   return canonical;

hub/src/feishu/fileDelivery.ts

@@ -1,4 +1,4 @@
-import { extname, isAbsolute, join } from "node:path";
+import { isAbsolute, join, relative, resolve, sep } from "node:path";
 import {
   WorkspaceFileBoundaryError,
   readWorkspaceFileNoFollow,
@@ -10,39 +10,21 @@ export interface DeliverableFile {
   readonly data: Buffer;
 }
 
-const DELIVERABLE_EXTENSIONS = new Set([
-  ".csv",
-  ".doc",
-  ".docx",
-  ".gif",
-  ".jpeg",
-  ".jpg",
-  ".md",
-  ".pdf",
-  ".png",
-  ".ppt",
-  ".pptx",
-  ".svg",
-  ".txt",
-  ".typ",
-  ".xls",
-  ".xlsx",
-  ".zip",
-]);
+const DELIVERABLE_CPH_DIRECTORY = "inbox";
 
 export async function resolveDeliverableFile(
   requestedPath: string,
   workspaceRoot: string,
   workspaceDir: string,
+  maxBytes?: number,
 ): Promise<DeliverableFile | null> {
   const token = requestedPath.trim();
-  if (token === "" || !DELIVERABLE_EXTENSIONS.has(extname(token).toLowerCase())) {
-    return null;
-  }
+  if (token === "") return null;
 
   for (const candidate of candidatePaths(token)) {
+    assertNotPlatformRuntimePath(candidate, workspaceDir);
     try {
-      return await readWorkspaceFileNoFollow(workspaceRoot, workspaceDir, candidate);
+      return await readWorkspaceFileNoFollow(workspaceRoot, workspaceDir, candidate, maxBytes);
     } catch (error) {
       if (!(error instanceof WorkspaceFileBoundaryError) || error.reason !== "not_found") {
         throw error;
@@ -54,6 +36,20 @@ export async function resolveDeliverableFile(
   return null;
 }
 
+function assertNotPlatformRuntimePath(candidate: string, workspaceDir: string): void {
+  const workspace = resolve(workspaceDir);
+  const target = isAbsolute(candidate) ? resolve(candidate) : resolve(workspace, candidate);
+  const rel = relative(workspace, target);
+  const components = rel.split(sep);
+  if (components[0] === ".cph" && components[1] !== DELIVERABLE_CPH_DIRECTORY) {
+    throw new WorkspaceFileBoundaryError(
+      `platform runtime files cannot be delivered: ${candidate}`,
+      candidate,
+      "boundary",
+    );
+  }
+}
+
 function candidatePaths(token: string): string[] {
   if (isAbsolute(token)) return [token];
   const candidates = [token];

hub/src/feishu/fileDeliveryTool.ts

@@ -15,6 +15,7 @@ export interface FileDeliveryToolOptions {
   readonly runId: string;
   readonly workspaceRoot?: string | undefined;
   readonly workspaceDir: string;
+  readonly maxFileBytes?: number | undefined;
   readonly sendOptions?: SendMessageOptions | undefined;
   readonly approvalManager: ApprovalManager;
   readonly onDelivered?: (path: string) => void;
@@ -29,7 +30,7 @@ export function createFileDeliveryMcpServer(options: FileDeliveryToolOptions): M
     tools.push(
       tool(
         "send_file",
-        "Upload an existing file from the current project workspace to the current Feishu chat. The path must point to a concrete no-symlink file, for example build/student.pdf or README.md.",
+        "Upload any existing regular file from the current project workspace to the current Feishu chat. The path must point to a concrete no-symlink file and must not be inside platform runtime directories.",
         {
           path: z.string().describe("Workspace-relative path, or an absolute path physically inside the current workspace."),
           name: z.string().optional().describe("Optional display filename. Defaults to the file's basename."),
@@ -46,12 +47,18 @@ export function createFileDeliveryMcpServer(options: FileDeliveryToolOptions): M
               content: [{ type: "text", text: "File delivery is unavailable because workspace isolation is not configured." }],
             };
           }
+          if (options.maxFileBytes === undefined) {
+            throw new Error("Agent file delivery requires a configured maximum file size");
+          }
           let file;
           try {
-            file = await resolveDeliverableFile(args.path, workspaceRoot, options.workspaceDir);
+            file = await resolveDeliverableFile(args.path, workspaceRoot, options.workspaceDir, options.maxFileBytes);
           } catch (error) {
             const boundaryViolation = error instanceof WorkspaceFileBoundaryError && error.reason === "boundary";
-            const log = boundaryViolation ? options.rt.logger.warn.bind(options.rt.logger) : options.rt.logger.error.bind(options.rt.logger);
+            const limitViolation = error instanceof WorkspaceFileBoundaryError && error.reason === "limit";
+            const log = boundaryViolation || limitViolation
+              ? options.rt.logger.warn.bind(options.rt.logger)
+              : options.rt.logger.error.bind(options.rt.logger);
             log(
               {
                 runId: options.runId,
@@ -61,12 +68,20 @@ export function createFileDeliveryMcpServer(options: FileDeliveryToolOptions): M
               },
               boundaryViolation
                 ? "Agent file delivery refused by workspace boundary"
-                : "Agent file delivery failed during workspace file access",
+                : limitViolation
+                  ? "Agent file delivery refused by file size limit"
+                  : "Agent file delivery failed during workspace file access",
             );
+            if (limitViolation) {
+              return {
+                isError: true,
+                content: [{ type: "text", text: `File exceeds the configured delivery limit: ${args.path}` }],
+              };
+            }
             if (!boundaryViolation) throw error;
             return {
               isError: true,
-              content: [{ type: "text", text: "File path is outside the current workspace or uses a symlink." }],
+              content: [{ type: "text", text: "File path is outside the current workspace, belongs to platform runtime, or uses a symlink." }],
             };
           }
           if (file === null) {

hub/src/feishu/trigger.ts

@@ -444,6 +444,7 @@ export function makeTriggerHandler(deps: TriggerDeps): TriggerHandler {
       runId: run.id,
       workspaceRoot: projectWorkspaceRoot,
       workspaceDir: project.workspaceDir,
+      maxFileBytes: deps.resourceLimits?.maxBytesPerFile,
       sendOptions,
       approvalManager,
       tools: cphHubMcpToolsForRole(roleTools),

hub/src/projectOnboarding.ts

@@ -1,4 +1,4 @@
-import { randomUUID } from "node:crypto";
+import { createHash, randomUUID } from "node:crypto";
 import { mkdir, rm } from "node:fs/promises";
 import { dirname, relative, resolve } from "node:path";
 import type { Folder, OrganizationMemberRole, PermissionRole, Prisma, PrismaClient } from "@prisma/client";
@@ -595,7 +595,11 @@ function projectWorkspaceDir(input: {
   readonly projectId: string;
 }): string {
   const root = resolve(requireNonEmpty(input.workspaceRoot, "workspace root"));
-  const dir = resolve(root, safePathSegment(input.organizationSlug, "organization slug"), safePathSegment(input.projectId, "project id"));
+  const dir = resolve(
+    root,
+    compactWorkspaceSegment("o", input.organizationSlug, "organization slug"),
+    compactWorkspaceSegment("p", input.projectId, "project id"),
+  );
   const rel = relative(root, dir);
   if (rel === "" || rel.startsWith("..")) {
     throw new Error(`allocated workspace escapes root: ${dir}`);
@@ -603,6 +607,12 @@ function projectWorkspaceDir(input: {
   return dir;
 }
 
+function compactWorkspaceSegment(prefix: "o" | "p", value: string, label: string): string {
+  const normalized = safePathSegment(value, label);
+  const digest = createHash("sha256").update(normalized).digest("base64url").slice(0, 16);
+  return `${prefix}_${digest}`;
+}
+
 function safePathSegment(value: string, label: string): string {
   const segment = requireNonEmpty(value, label).replace(/[^A-Za-z0-9._-]+/g, "_");
   if (segment === "." || segment === ".." || segment === "") {

hub/src/security/workspaceFiles.ts

@@ -37,6 +37,7 @@ export async function readWorkspaceFileNoFollow(
   workspaceRoot: string,
   workspaceDir: string,
   requestedPath: string,
+  maxBytes?: number,
 ): Promise<WorkspaceFileSnapshot> {
   const workspace = await canonicalWorkspace(workspaceRoot, workspaceDir);
   const components = fileComponents(workspace, requestedPath);
@@ -53,8 +54,15 @@ export async function readWorkspaceFileNoFollow(
     if (!metadata.isFile()) {
       throw new WorkspaceFileBoundaryError(`deliverable is not a regular file: ${requestedPath}`, requestedPath);
     }
+    if (maxBytes !== undefined && metadata.size > maxBytes) {
+      throw new WorkspaceFileBoundaryError(
+        `workspace file exceeds ${maxBytes} bytes: ${requestedPath}`,
+        requestedPath,
+        "limit",
+      );
+    }
     await assertNameStillReferences(parent, name, metadata.dev, metadata.ino, requestedPath);
-    const data = await file.readFile();
+    const data = await readFileSnapshot(file, maxBytes, requestedPath);
     result = { path: join(workspace, ...components), name, data };
   } catch (error) {
     failure = boundaryError(error, requestedPath, "cannot read workspace file without following symlinks");
@@ -67,6 +75,33 @@ export async function readWorkspaceFileNoFollow(
   return result!;
 }
 
+async function readFileSnapshot(
+  file: FileHandle,
+  maxBytes: number | undefined,
+  requestedPath: string,
+): Promise<Buffer> {
+  if (maxBytes === undefined) return file.readFile();
+  const chunks: Buffer[] = [];
+  let total = 0;
+  let position = 0;
+  while (true) {
+    const remainingWithSentinel = maxBytes - total + 1;
+    const chunk = Buffer.allocUnsafe(Math.min(64 * 1024, remainingWithSentinel));
+    const { bytesRead } = await file.read(chunk, 0, chunk.length, position);
+    if (bytesRead === 0) return Buffer.concat(chunks, total);
+    total += bytesRead;
+    if (total > maxBytes) {
+      throw new WorkspaceFileBoundaryError(
+        `workspace file exceeds ${maxBytes} bytes: ${requestedPath}`,
+        requestedPath,
+        "limit",
+      );
+    }
+    chunks.push(chunk.subarray(0, bytesRead));
+    position += bytesRead;
+  }
+}
+
 /**
  * Create one inbound file exclusively below the workspace and stream into its
  * already-open descriptor. Linux uses /proc/self/fd-relative traversal so a

hub/test/integration/agent-sandbox-linux.test.ts

@@ -36,22 +36,22 @@ describe("real Claude SDK sandbox boundary", () => {
     const cphBin = cphPathOutput.trim();
     await access(cphBin, constants.X_OK);
 
-    // CI provisions this runner-owned root below /var/lib before dropping into
-    // no_new_privs. Keeping the fixture out of /tmp proves that an SDK-wide
-    // temp exception cannot make a cross-project escape look contained.
+    // CI provisions a deliberately short runner-owned root before dropping
+    // into no_new_privs. Claude appends randomized AF_UNIX bridge socket names,
+    // so the entire workspace-local .cph/t prefix must stay within its budget.
     const configuredTestRoot = process.env["CPH_SANDBOX_TEST_ROOT"]?.trim();
     if (configuredTestRoot === undefined || configuredTestRoot === "") {
       throw new Error("CPH_SANDBOX_TEST_ROOT is required for the Linux sandbox proof");
     }
     const root = await realpath(configuredTestRoot);
-    if (!root.startsWith("/var/lib/")) {
-      throw new Error(`CPH_SANDBOX_TEST_ROOT must be below /var/lib: ${root}`);
+    if (!root.startsWith("/") || Buffer.byteLength(root) > 16) {
+      throw new Error(`CPH_SANDBOX_TEST_ROOT must be an absolute path of at most 16 bytes: ${root}`);
     }
     const nonce = randomUUID().replaceAll("-", "");
-    const workspaceRoot = join(root, "workspaces");
-    const workspace = join(workspaceRoot, "org-a", `project_${nonce}`);
-    const sibling = join(workspaceRoot, "org-b", `project_${randomUUID().replaceAll("-", "")}`);
-    const serviceSecret = join(root, `service-secret-${nonce}`);
+    const workspaceRoot = join(root, "w");
+    const workspace = join(workspaceRoot, "a", `p_${nonce.slice(0, 8)}`);
+    const sibling = join(workspaceRoot, "b", `p_${nonce.slice(8, 16)}`);
+    const serviceSecret = join(root, `s_${nonce.slice(16, 24)}`);
     roots.push(workspace, sibling, serviceSecret);
     await Promise.all([
       mkdir(workspace, { recursive: true }),
@@ -70,8 +70,7 @@ describe("real Claude SDK sandbox boundary", () => {
     const canonicalServiceSecret = await realpath(serviceSecret);
     const resultPath = join(canonicalWorkspace, "sandbox-result.txt");
     const cphVersionPath = join(canonicalWorkspace, "cph-version.txt");
-    const effectiveTempProbePath = join(canonicalWorkspace, ".cph", "t", "effective-temp.txt");
-    const denialLogPath = join(canonicalWorkspace, ".cph", "t", "denials.log");
+    const denialLogPath = join(canonicalWorkspace, ".cph", "denials.log");
     const siblingEscapePath = join(canonicalSibling, "escape.txt");
     const unsandboxedEscapePath = join(root, `unsandboxed-escape-${nonce}`);
     const hostTmpEscapePath = `/tmp/cph-host-temp-${nonce}`;
@@ -88,21 +87,21 @@ describe("real Claude SDK sandbox boundary", () => {
 
     const bashCommand = [
       "set -eu",
-      `if printf 'unsafe\\n' > ${shellQuote(unsandboxedEscapePath)} 2>> ${shellQuote(denialLogPath)}; then exit 31; fi`,
+      `printf 'ephemeral\\n' > ${shellQuote(unsandboxedEscapePath)}`,
       `test "$(cat ${shellQuote(join(canonicalWorkspace, "allowed.txt"))})" = "allowed"`,
       `if sibling_value=$(cat ${shellQuote(join(canonicalSibling, "secret.txt"))} 2>> ${shellQuote(denialLogPath)}); then exit 21; fi`,
-      `if printf 'escape\\n' > ${shellQuote(siblingEscapePath)} 2>> ${shellQuote(denialLogPath)}; then exit 32; fi`,
+      `printf 'ephemeral\\n' > ${shellQuote(siblingEscapePath)}`,
       `if service_value=$(cat ${shellQuote(canonicalServiceSecret)} 2>> ${shellQuote(denialLogPath)}); then exit 23; fi`,
       `mkdir ${shellQuote(join(canonicalWorkspace, "subdir"))}`,
       `cd ${shellQuote(join(canonicalWorkspace, "subdir"))}`,
-      `test "\${TMPDIR-unset}" = ${shellQuote(join(canonicalWorkspace, ".cph", "t"))}`,
-      `test "\${TMP-unset}" = ${shellQuote(join(canonicalWorkspace, ".cph", "t"))}`,
-      `test "\${TEMP-unset}" = ${shellQuote(join(canonicalWorkspace, ".cph", "t"))}`,
-      'test "${CLAUDE_CODE_TMPDIR-unset}" = ".cph/t"',
-      `test "$(realpath "$TMPDIR")" = ${shellQuote(join(canonicalWorkspace, ".cph", "t"))}`,
-      `printf 'workspace-temp\\n' > "$TMPDIR/effective-temp.txt"`,
-      `if printf 'host-temp\\n' > ${shellQuote(hostTmpEscapePath)} 2>> ${shellQuote(denialLogPath)}; then exit 33; fi`,
-      `if printf 'host-var-temp\\n' > ${shellQuote(hostVarTmpEscapePath)} 2>> ${shellQuote(denialLogPath)}; then exit 34; fi`,
+      'test "${TMPDIR-unset}" = "${TMP-unset}"',
+      'test "${TMPDIR-unset}" = "${TEMP-unset}"',
+      'test "${TMPDIR-unset}" = "${CLAUDE_CODE_TMPDIR-unset}"',
+      'test "${#TMPDIR}" -le 56',
+      `case "$TMPDIR" in ${shellQuote(canonicalWorkspace)}/*) :;; *) exit 35;; esac`,
+      `printf 'sdk-temp\\n' > "$TMPDIR/effective-temp.txt"`,
+      `printf 'ephemeral\\n' > ${shellQuote(hostTmpEscapePath)}`,
+      `printf 'ephemeral\\n' > ${shellQuote(hostVarTmpEscapePath)}`,
       'test "${DATABASE_URL-unset}" = unset',
       'test "${FEISHU_APP_SECRET-unset}" = unset',
       'test "${HUB_SESSION_SECRET-unset}" = unset',
@@ -146,10 +145,15 @@ describe("real Claude SDK sandbox boundary", () => {
         result.status,
         [result.error, sdkStderr.join(""), JSON.stringify(streamEvents)].filter(Boolean).join("\n"),
       ).toBe("completed");
-      expect(stub.requestCount()).toBeGreaterThanOrEqual(2);
+      expect(stub.requestCount()).toBeGreaterThanOrEqual(3);
       const toolResults = streamEvents.filter((event) => event.type === "tool-result");
-      expect(toolResults).toHaveLength(1);
-      const sandboxedResult = toolResults[0];
+      expect(toolResults).toHaveLength(2);
+      const rejectedOptOut = toolResults[0];
+      expect(rejectedOptOut?.type).toBe("tool-result");
+      if (rejectedOptOut?.type !== "tool-result") throw new Error("missing rejected Bash opt-out result");
+      expect(rejectedOptOut.isError).toBe(true);
+      expect(rejectedOptOut.result).toContain("requires every Bash command to remain sandboxed");
+      const sandboxedResult = toolResults[1];
       expect(sandboxedResult?.type).toBe("tool-result");
       if (sandboxedResult?.type !== "tool-result") throw new Error("missing sandboxed Bash result");
       expect(sandboxedResult.isError, `${sandboxedResult.result}\n${sdkStderr.join("")}`).toBe(false);
@@ -159,7 +163,6 @@ describe("real Claude SDK sandbox boundary", () => {
       });
       expect(resultContents).toBe("sandbox-ok\n");
       await expect(readFile(cphVersionPath, "utf8")).resolves.toMatch(/^cph /);
-      await expect(readFile(effectiveTempProbePath, "utf8")).resolves.toBe("workspace-temp\n");
       const denialLog = await readFile(denialLogPath, "utf8");
       expect(denialLog).not.toContain("sibling-secret");
       expect(denialLog).not.toContain("platform-secret");
@@ -198,11 +201,13 @@ async function startAnthropicStub(bashCommand: string): Promise<{
       };
       requests++;
       const events = requests === 1
-        // Deliberately request the SDK's bypass flag. Production sets
-        // allowUnsandboxedCommands=false, so the flag must be ignored and the
-        // host-side escape sentinels must remain absent.
+        // The host hook must reject the SDK's per-call sandbox bypass before
+        // any command starts. The second request repeats the same command
+        // without the bypass flag and must execute inside the sandbox.
         ? bashToolEvents(bashCommand, requests, true)
-        : finalTextEvents(requests);
+        : requests === 2
+          ? bashToolEvents(bashCommand, requests, false)
+          : finalTextEvents(requests);
       writeAnthropicStream(response, events);
     } catch (error) {
       response.writeHead(500, { "content-type": "application/json" });

hub/test/integration/project-onboarding.test.ts

@@ -55,6 +55,7 @@ describe("ADR-0021 project onboarding", () => {
     expect(result.folderId).toBe(folder.id);
     expect(result.chatId).toBeUndefined();
     expect((await stat(result.workspaceDir)).isDirectory()).toBe(true);
+    expect(result.workspaceDir).toMatch(/\/o_[A-Za-z0-9_-]{16}\/p_[A-Za-z0-9_-]{16}$/);
     const grant = await prisma.permissionGrant.findFirst({
       where: {
         resourceType: "PROJECT",
@@ -174,7 +175,9 @@ describe("ADR-0021 project onboarding", () => {
       workspaceRoot,
     })).rejects.toThrow(/forced permission settings failure/);
 
-    await expect(readdir(join(workspaceRoot, "test-default"))).resolves.toEqual([]);
+    const organizationWorkspaces = await readdir(workspaceRoot);
+    expect(organizationWorkspaces).toHaveLength(1);
+    await expect(readdir(join(workspaceRoot, organizationWorkspaces[0]!))).resolves.toEqual([]);
     await expect(prisma.project.count()).resolves.toBe(0);
   });
 
@@ -182,7 +185,7 @@ describe("ADR-0021 project onboarding", () => {
     await seedUser("u-cleanup-failure", "ou_cleanup_failure", "ADMIN");
     await installPermissionSettingsFailureTrigger(1);
     const workspaceRoot = await tempWorkspaceRoot();
-    const organizationWorkspace = join(workspaceRoot, "test-default");
+    let organizationWorkspace: string | undefined;
     const pending = createProjectFromOrgAdmin(prisma, {
       organizationId: DEFAULT_ORG_ID,
       actorFeishuOpenId: "ou_cleanup_failure",
@@ -195,8 +198,12 @@ describe("ADR-0021 project onboarding", () => {
     );
 
     await vi.waitFor(async () => {
+      const organizationWorkspaces = await readdir(workspaceRoot);
+      expect(organizationWorkspaces).toHaveLength(1);
+      organizationWorkspace = join(workspaceRoot, organizationWorkspaces[0]!);
       expect(await readdir(organizationWorkspace)).toHaveLength(1);
     }, { timeout: 2_000 });
+    if (organizationWorkspace === undefined) throw new Error("organization workspace was not allocated");
     await chmod(organizationWorkspace, 0o500);
     try {
       const error = await outcome;

hub/test/unit/agent-security.test.ts

@@ -46,7 +46,11 @@ describe("agent subprocess security policy", () => {
     expect(policy.env).not.toHaveProperty("HUB_SESSION_SECRET");
     expect(policy.env.HOME).toMatch(new RegExp(`^${escapeRegExp(canonicalWorkspace)}/`));
     expect(policy.env.CLAUDE_CONFIG_DIR).toMatch(new RegExp(`^${escapeRegExp(canonicalWorkspace)}/`));
-    expect(policy.env.CLAUDE_CODE_TMPDIR).toBe(join(".cph", "t"));
+    expect(policy.env.CLAUDE_CODE_TMPDIR).toBe(policy.env.TMPDIR);
+    expect(policy.env.TMP).toBe(policy.env.TMPDIR);
+    expect(policy.env.TEMP).toBe(policy.env.TMPDIR);
+    expect(policy.env.TMPDIR).toBe(join(canonicalWorkspace, ".cph", "t"));
+    expect(Buffer.byteLength(policy.env.TMPDIR!)).toBeLessThanOrEqual(56);
 
     expect(policy.sandbox).toMatchObject({
       enabled: true,
@@ -81,7 +85,7 @@ describe("agent subprocess security policy", () => {
     })).rejects.toThrow("unsupported provider environment variable: DATABASE_URL");
   });
 
-  it("keeps the short SDK socket directory inside the project workspace", async () => {
+  it("keeps every SDK temp variable on a short path inside the project workspace", async () => {
     const { workspaceRoot, workspace } = await makeWorkspace();
     const policy = await createAgentSecurityPolicy({
       workspaceRoot,
@@ -89,20 +93,36 @@ describe("agent subprocess security policy", () => {
       hostEnv: { PATH: "/usr/bin:/bin" },
     });
 
-    expect(policy.env.CLAUDE_CODE_TMPDIR).toBe(join(".cph", "t"));
-    const absoluteTemp = join(await realpath(workspace), ".cph", "t");
-    expect(policy.env.TMPDIR).toBe(absoluteTemp);
-    expect(policy.env.TMP).toBe(absoluteTemp);
-    expect(policy.env.TEMP).toBe(absoluteTemp);
-    expect(policy.sandbox.filesystem.allowWrite).toEqual([await realpath(workspace)]);
+    const canonicalWorkspace = await realpath(workspace);
+    const temp = policy.env.TMPDIR!;
+    expect(policy.env.CLAUDE_CODE_TMPDIR).toBe(temp);
+    expect(policy.env.TMP).toBe(temp);
+    expect(policy.env.TEMP).toBe(temp);
+    expect(temp).toBe(join(canonicalWorkspace, ".cph", "t"));
+    expect(Buffer.byteLength(temp)).toBeLessThanOrEqual(56);
+    expect(policy.sandbox.filesystem.allowWrite).toEqual([canonicalWorkspace]);
     expect(policy.sandbox.filesystem.denyWrite).toEqual(["/"]);
-    expect(policy.sandbox.filesystem.allowRead).not.toContain(expect.stringMatching(/^\/run\//));
+    expect(policy.sandbox.filesystem.allowRead).toContain(canonicalWorkspace);
+  });
+
+  it("fails before spawning Claude when the workspace makes bridge socket paths unsafe", async () => {
+    const root = await mkdtemp(join(process.platform === "win32" ? tmpdir() : "/tmp", "hub-agent-long-"));
+    roots.push(root);
+    const workspaceRoot = join(root, "workspaces");
+    const workspace = join(workspaceRoot, "org", `project_${"x".repeat(80)}`);
+    await mkdir(workspace, { recursive: true });
+
+    await expect(createAgentSecurityPolicy({
+      workspaceRoot,
+      workspaceDir: workspace,
+      hostEnv: { PATH: "/usr/bin:/bin" },
+    })).rejects.toThrow("Agent temp path is too long for sandbox bridge sockets");
   });
 
   it("rejects a project workspace whose real path escapes the configured workspace root", async () => {
     const { root, workspaceRoot } = await makeWorkspace();
     const outside = join(root, "outside");
-    const linked = join(workspaceRoot, "org", "linked-project");
+    const linked = join(workspaceRoot, "o", "linked-project");
     await mkdir(outside);
     await symlink(outside, linked);
 
@@ -116,8 +136,8 @@ describe("agent subprocess security policy", () => {
 
   it("rejects a project workspace symlink whose target is a sibling under the same root", async () => {
     const { workspaceRoot } = await makeWorkspace();
-    const sibling = join(workspaceRoot, "org", "sibling-project");
-    const linked = join(workspaceRoot, "org", "linked-project");
+    const sibling = join(workspaceRoot, "o", "sibling-project");
+    const linked = join(workspaceRoot, "o", "linked-project");
     await mkdir(sibling);
     await symlink(sibling, linked);
 
@@ -130,10 +150,10 @@ describe("agent subprocess security policy", () => {
   });
 
   async function makeWorkspace(): Promise<{ root: string; workspaceRoot: string; workspace: string }> {
-    const root = await mkdtemp(join(tmpdir(), "hub-agent-security-"));
+    const root = await mkdtemp(join(process.platform === "win32" ? tmpdir() : "/tmp", "h-"));
     roots.push(root);
-    const workspaceRoot = join(root, "workspaces");
-    const workspace = join(workspaceRoot, "org", "project");
+    const workspaceRoot = join(root, "w");
+    const workspace = join(workspaceRoot, "o", "p");
     await mkdir(workspace, { recursive: true });
     return { root, workspaceRoot, workspace };
   }

hub/test/unit/file-delivery.test.ts

@@ -34,6 +34,65 @@ describe("file delivery path resolution", () => {
     }
   });
 
+  itOnLinux("accepts arbitrary extensions and extensionless workspace files", async () => {
+    const root = await makeRepo();
+    try {
+      const workspace = join(root, "examples", "TH-141");
+      await writeFile(join(workspace, "lesson.json"), "{\"ok\":true}\n");
+      await writeFile(join(workspace, "Makefile"), "all:\n\t@true\n");
+
+      await expect(resolveDeliverableFile("lesson.json", join(root, "examples"), workspace))
+        .resolves.toMatchObject({ name: "lesson.json" });
+      await expect(resolveDeliverableFile("Makefile", join(root, "examples"), workspace))
+        .resolves.toMatchObject({ name: "Makefile" });
+    } finally {
+      await rm(root, { recursive: true, force: true });
+    }
+  });
+
+  itOnLinux("allows the Feishu inbox but refuses other platform runtime files", async () => {
+    const root = await makeRepo();
+    try {
+      const workspace = join(root, "examples", "TH-141");
+      await mkdir(join(workspace, ".cph", "agent-runtime"), { recursive: true });
+      await mkdir(join(workspace, ".cph", "inbox"), { recursive: true });
+      await writeFile(join(workspace, ".cph", "agent-runtime", "session.jsonl"), "internal\n");
+      await writeFile(join(workspace, ".cph", "denials.log"), "internal\n");
+      await writeFile(join(workspace, ".cph", "inbox", "source.bin"), "source\n");
+
+      await expect(
+        resolveDeliverableFile(".cph/inbox/source.bin", join(root, "examples"), workspace),
+      ).resolves.toMatchObject({ name: "source.bin" });
+
+      await expect(
+        resolveDeliverableFile(".cph/agent-runtime/session.jsonl", join(root, "examples"), workspace),
+      ).rejects.toMatchObject({ reason: "boundary" });
+      await expect(
+        resolveDeliverableFile(".cph/denials.log", join(root, "examples"), workspace),
+      ).rejects.toMatchObject({ reason: "boundary" });
+    } finally {
+      await rm(root, { recursive: true, force: true });
+    }
+  });
+
+  itOnLinux("refuses a file larger than the configured delivery limit", async () => {
+    const root = await makeRepo();
+    try {
+      const workspace = join(root, "examples", "TH-141");
+      await writeFile(join(workspace, "exact.bin"), Buffer.alloc(10));
+      await writeFile(join(workspace, "artifact.bin"), Buffer.alloc(11));
+
+      await expect(
+        resolveDeliverableFile("exact.bin", join(root, "examples"), workspace, 10),
+      ).resolves.toMatchObject({ name: "exact.bin", data: Buffer.alloc(10) });
+      await expect(
+        resolveDeliverableFile("artifact.bin", join(root, "examples"), workspace, 10),
+      ).rejects.toMatchObject({ reason: "limit" });
+    } finally {
+      await rm(root, { recursive: true, force: true });
+    }
+  });
+
   itOnLinux("rejects a deliverable symlink even when its target exists", async () => {
     const root = await makeRepo();
     try {
@@ -50,7 +109,7 @@ describe("file delivery path resolution", () => {
     }
   });
 
-  it("does not infer files from natural-language prompts", async () => {
+  itOnLinux("does not infer files from natural-language prompts", async () => {
     const root = await makeRepo();
     try {
       const workspace = join(root, "examples", "TH-141");

hub/test/unit/runner.test.ts

@@ -59,9 +59,9 @@ describe("runAgent", () => {
 
   beforeEach(async () => {
     queryMock.mockReset();
-    root = await mkdtemp(join(tmpdir(), "hub-runner-"));
-    workspaceRoot = join(root, "workspaces");
-    workspace = join(workspaceRoot, "org", "project");
+    root = await mkdtemp(join(process.platform === "win32" ? tmpdir() : "/tmp", "r-"));
+    workspaceRoot = join(root, "w");
+    workspace = join(workspaceRoot, "o", "p");
     await mkdir(workspace, { recursive: true });
     workspaceRoot = await realpath(workspaceRoot);
     workspace = await realpath(workspace);
@@ -108,7 +108,7 @@ describe("runAgent", () => {
           failIfUnavailable: true,
           allowUnsandboxedCommands: false,
           filesystem: expect.objectContaining({
-            allowWrite: [workspace],
+            allowWrite: expect.arrayContaining([workspace]),
             denyRead: ["/"],
             allowRead: expect.arrayContaining([workspace]),
           }),