Add configurable Hub API MCP endpoint (0.177.0)

Expose MCP enabled/origin settings in Hub chart values and API deployment, with schema validation, documentation and rendering checks.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

charts/hub/Chart.yaml

@@ -16,7 +16,7 @@ type: application
 # This is the chart version. This version number should be incremented each time you make changes
 # to the chart and its templates, including the app version.
 # Versions are expected to follow Semantic Versioning (https://semver.org/)
-version: 0.176.0
+version: 0.177.0
 
 # This is the version number of the application being deployed. This version number should be
 # incremented each time you make changes to the application. Versions are not expected to

charts/hub/README.md

@@ -335,6 +335,34 @@ ownership on existing optional `LOCAL_CACHE_DIRECTORY` mounts. Its liveness
 endpoint is `GET /api/health`. Wire those settings in the actual Vault deployment
 only when a compatible image release is selected; no migration is required.
 
+### MCP
+
+Deploy a Hub API image supporting MCP, then enable the read-only Streamable HTTP
+endpoint at `/mcp`:
+
+```yaml
+kerberoshub:
+    api:
+        mcp:
+            enabled: true
+            allowedOrigins: []
+```
+
+After upgrading the Helm release, an unauthenticated request to `/mcp` should
+return `401` instead of `404`. Connect using HTTPS and an existing Hub access
+token in `Authorization: Bearer <token>`; browser-session JWTs and cookies cannot
+authenticate MCP. Recording tools require `media.read`, device tools require
+`devices.read`, and both require effective resource grants.
+
+VS Code and other clients without an `Origin` header need no `allowedOrigins`.
+For browser MCP clients, list exact origins such as `https://agent.example.com`.
+Wildcards and trailing slashes are not supported. These origins are independent
+of REST CORS; frontend and REST origins are not automatically copied into MCP.
+MCP stays disabled by default, and these settings apply only to Hub API pods
+in `all` and `ui` modes. The chart does not change the API image tag.
+
+Validate rendering with `bash scripts/check-hub-mcp.sh` from the repository root.
+
 ### Passkeys
 
 Users and sub-users can create and manage their own passkeys in **Profile >
@@ -697,6 +725,8 @@ kerberospipeline:
 | `kerberoshub.api.schema` | The protocol to serve the Kerberos Hub API, `'http'` or `'https'`. | `"https"` |
 | `kerberoshub.api.url` | The Kerberos Hub API ingress to access the API. | `"api.yourdomain.com"` |
 | `kerberoshub.api.corsAllowedOrigins` | Additional complete HTTP(S) origins allowed to call the Hub API. Configured frontend origins remain allowed automatically. | `[]` |
+| `kerberoshub.api.mcp.enabled` | Expose the read-only `/mcp` endpoint; sets `MCP_ENABLED`. Requires a compatible Hub API image. | `false` |
+| `kerberoshub.api.mcp.allowedOrigins` | Exact HTTP(S) origins for browser MCP clients, joined into `MCP_ALLOWED_ORIGINS`. Independent of REST CORS; no wildcards or trailing slash. | `[]` |
 | `kerberoshub.api.disableAgentHeartbeat` | Temporarily stop serving the polled `GET /devices` list (hub-api returns `204` without database reads). Devices still load once through `/session/bootstrap`; online/offline status stops refreshing. | `false` |
 | `kerberoshub.api.mediaProxy.enabled` | Serve media through hub-api (`/media/proxy`) instead of handing out Vault/storage URLs, hiding the storage endpoint from clients. | `false` |
 | `kerberoshub.api.mediaProxy.publicUrl` | Public hub-api base URL used in proxied media URLs. Defaults to `{schema}://{url}`. | `""` |

charts/hub/templates/kerberos-hub/hub-api.yaml

@@ -323,6 +323,11 @@ spec:
             {{- end }}
             - name: CORS_ALLOWED_ORIGINS
               value: {{ join "," $corsOrigins | quote }}
+            {{- $mcp := .Values.kerberoshub.api.mcp | default dict }}
+            - name: MCP_ENABLED
+              value: {{ $mcp.enabled | default false | quote }}
+            - name: MCP_ALLOWED_ORIGINS
+              value: {{ join "," ($mcp.allowedOrigins | default list) | quote }}
             {{ if .Values.isPrivate }}
             - name: KERBEROS_PRIVATE_CLOUD
               value: "true"

charts/hub/values.schema.json

@@ -62,6 +62,22 @@
         "api": {
           "type": "object",
           "properties": {
+            "mcp": {
+              "type": "object",
+              "additionalProperties": false,
+              "properties": {
+                "enabled": {"type": "boolean"},
+                "allowedOrigins": {
+                  "type": "array",
+                  "uniqueItems": true,
+                  "items": {
+                    "type": "string",
+                    "pattern": "^https?://[^/?#*@,\\s]+$"
+                  },
+                  "description": "Exact HTTP(S) origins for browser MCP clients, without wildcards, credentials, paths or trailing slashes. Independent of REST CORS."
+                }
+              }
+            },
             "passkeys": {
               "type": "object",
               "additionalProperties": false,

charts/hub/values.yaml

@@ -370,6 +370,12 @@ kerberoshub:
     # Additional complete HTTP(S) origins allowed to call the Hub API.
     # The configured frontend origins remain allowed automatically.
     corsAllowedOrigins: []
+    # Read-only Streamable HTTP MCP endpoint at /mcp; requires a compatible API image.
+    mcp:
+      enabled: false
+      # Exact HTTP(S) origins for browser MCP clients; no wildcards or trailing slash.
+      # Clients without an Origin header (such as VS Code) need no entries.
+      allowedOrigins: []
     # Temporarily stop serving the polled GET /devices list: hub-api answers 204
     # without querying MongoDB. The frontend still loads devices once through
     # /session/bootstrap, but device online/offline status stops refreshing.

scripts/check-hub-mcp.sh

@@ -0,0 +1,86 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+CHART_DIR="${1:-charts/hub}"
+
+extract_mcp() {
+  awk '
+    /^---/ { deployment=0; name=""; variable="" }
+    /^kind: Deployment$/ { deployment=1 }
+    deployment && /^  name:/ { name=$2 }
+    /- name: MCP_/ { variable=$3; next }
+    variable != "" && /value:/ {
+      value=$0
+      sub(/^[[:space:]]*value: /, "", value)
+      print (deployment ? name : "non-deployment"), variable, value
+      variable=""
+    }
+  ' | sort
+}
+
+assert_mcp() {
+  local rendered="$1" expected="$2" actual
+  actual="$(printf '%s\n' "$rendered" | extract_mcp)"
+  if [[ "$actual" != "$expected" ]]; then
+    printf 'Unexpected MCP environment:\n%s\nExpected:\n%s\n' "$actual" "$expected" >&2
+    return 1
+  fi
+}
+
+defaults="$(printf '%s\n' 'hub-api MCP_ALLOWED_ORIGINS ""' 'hub-api MCP_ENABLED "false"')"
+enabled="$(printf '%s\n' \
+  'hub-api MCP_ALLOWED_ORIGINS "https://agent.example.com,http://localhost:4200"' \
+  'hub-api MCP_ENABLED "true"')"
+flags=(
+  --set kerberoshub.api.mcp.enabled=true
+  --set-json 'kerberoshub.api.mcp.allowedOrigins=["https://agent.example.com","http://localhost:4200"]'
+)
+
+for mode in all ui pipeline; do
+  default_render="$(helm template hub "$CHART_DIR" --set "mode=$mode")"
+  configured_render="$(helm template hub "$CHART_DIR" --set "mode=$mode" "${flags[@]}")"
+  helm lint "$CHART_DIR" --quiet --set "mode=$mode" "${flags[@]}"
+  if [[ "$mode" == pipeline ]]; then
+    assert_mcp "$default_render" ""
+    assert_mcp "$configured_render" ""
+    [[ "$default_render" == "$configured_render" ]]
+  else
+    assert_mcp "$default_render" "$defaults"
+    assert_mcp "$configured_render" "$enabled"
+    rest_default="$(grep -A1 -- '- name: CORS_ALLOWED_ORIGINS' <<< "$default_render")"
+    rest_configured="$(grep -A1 -- '- name: CORS_ALLOWED_ORIGINS' <<< "$configured_render")"
+    [[ "$rest_default" == "$rest_configured" ]]
+  fi
+  echo "OK ($mode): MCP defaults, overrides, API-only environment and REST CORS isolation"
+done
+
+assert_mcp "$(helm template hub "$CHART_DIR" --set kerberoshub.api.mcp.enabled=true)" \
+  "$(printf '%s\n' 'hub-api MCP_ALLOWED_ORIGINS ""' 'hub-api MCP_ENABLED "true"')"
+assert_mcp "$(helm template hub "$CHART_DIR" --set kerberoshub.api.mcp=null)" "$defaults"
+assert_mcp "$(helm template hub "$CHART_DIR" "${flags[@]}" --set kerberoshub.api.mcp.enabled=false)" \
+  "$(printf '%s\n' 'hub-api MCP_ALLOWED_ORIGINS "https://agent.example.com,http://localhost:4200"' 'hub-api MCP_ENABLED "false"')"
+
+expect_invalid() {
+  local output
+  if output="$(helm template hub "$CHART_DIR" "$@" 2>&1)"; then
+    echo "Invalid MCP settings unexpectedly rendered: $*" >&2
+    return 1
+  fi
+  if [[ "$output" != *"mcp"* ]]; then
+    printf 'Rendering failed for an unexpected reason:\n%s\n' "$output" >&2
+    return 1
+  fi
+}
+
+expect_invalid --set-string kerberoshub.api.mcp.enabled=true
+expect_invalid --set-string kerberoshub.api.mcp.allowedOrigins=https://agent.example.com
+expect_invalid --set-string kerberoshub.api.mcp.origin=https://agent.example.com
+for origin in 'https://*.example.com' 'https://agent.example.com/' \
+  'https://agent.example.com/path' 'https://agent.example.com?query' \
+  'https://agent.example.com#fragment' 'https://user@agent.example.com' \
+  'https://agent.example.com,https://other.example.com' 'https://bad host' 'ftp://agent.example.com'; do
+  expect_invalid --set-json "kerberoshub.api.mcp.allowedOrigins=[\"$origin\"]"
+done
+expect_invalid --set-json 'kerberoshub.api.mcp.allowedOrigins=["https://agent.example.com","https://agent.example.com"]'
+
+echo "All Hub MCP configuration checks passed."