diff --git a/backend/__tests__/unit/services/externalFeedService.test.js b/backend/__tests__/unit/services/externalFeedService.test.js
index 0fe290c6eb..c8696521c5 100644
--- a/backend/__tests__/unit/services/externalFeedService.test.js
+++ b/backend/__tests__/unit/services/externalFeedService.test.js
@@ -232,6 +232,11 @@ describe('externalFeedService', () => {
         $set: expect.objectContaining({
           status: 'error',
           errorMessage: 'invalid_request',
+          // Named, not omitted (wren 73858): a `$set` that leaves a key out
+          // inherits the row's stored value, so silence here would keep a stale
+          // `true` from an earlier human-authored reason and print this
+          // provider text in the user's connector list.
+          errorMessageUserFacing: false,
         }),
       }),
     );
diff --git a/backend/__tests__/unit/services/installableCatalogService.test.js b/backend/__tests__/unit/services/installableCatalogService.test.js
index 2c36f8c50b..2db7b55ee4 100644
--- a/backend/__tests__/unit/services/installableCatalogService.test.js
+++ b/backend/__tests__/unit/services/installableCatalogService.test.js
@@ -40,6 +40,46 @@ const githubTool = () => ({
 describe('installable catalog service', () => {
   beforeEach(() => jest.clearAllMocks());
 
+  it('carries the flag beside the message, so the page can tell a reason from an exception', async () => {
+    mockInstallables([
+      { installableId: 'telegram', name: 'Telegram', description: 'Telegram description' },
+      { installableId: 'slack', name: 'Slack', description: 'Slack description' },
+    ]);
+    InstallableInstallation.find.mockReturnValue(lean([
+      {
+        _id: installationId,
+        installableId: 'telegram',
+        status: 'error',
+        errorMessage: "This connector's channel is gone. Retry to rebuild it.",
+        // The reconciler's own constant: a writer declared it readable.
+        errorMessageUserFacing: true,
+        targetId: userId,
+        installedBy: userId,
+        components: [],
+      },
+      {
+        _id: '6a8f6dc7a1dccf2e02f31099',
+        installableId: 'slack',
+        status: 'error',
+        // `markProjectionFailure`'s raw exception: the same field, a different
+        // kind of string, and the flag is what separates them.
+        errorMessage: 'connect ECONNREFUSED 10.4.4.7:443',
+        targetId: userId,
+        installedBy: userId,
+        components: [],
+      },
+    ]));
+    Integration.find.mockReturnValue(lean([]));
+
+    const catalog = await catalogFor(userId);
+    const byId = Object.fromEntries(catalog.installables.map((entry) => [entry.installableId, entry.installation]));
+
+    expect(byId.telegram.errorMessageUserFacing).toBe(true);
+    expect(byId.slack.errorMessageUserFacing).toBe(false);
+    // The message still travels — the page, not the mapper, decides what to show.
+    expect(byId.slack.errorMessage).toBe('connect ECONNREFUSED 10.4.4.7:443');
+  });
+
   it('returns provider readiness and the caller parent without leaking private fields', async () => {
     mockInstallables([
       { installableId: 'telegram', name: 'Telegram', description: 'Telegram description' },
@@ -49,7 +89,7 @@ describe('installable catalog service', () => {
       _id: installationId,
       installableId: 'telegram',
       status: 'error',
-      errorMessage: 'projection missing',
+      errorMessage: "This connector's channel is gone. Retry to rebuild it.",
       targetId: 'another-user',
       installedBy: 'another-user',
       claimId: 'private-claim',
@@ -89,7 +129,10 @@ describe('installable catalog service', () => {
         available: true,
         installation: {
           status: 'error',
-          errorMessage: 'projection missing',
+          errorMessage: "This connector's channel is gone. Retry to rebuild it.",
+          // The mapper hands over the provenance with the message, so the page
+          // never has to guess from the shape of the string (TASK-131).
+          errorMessageUserFacing: false,
           boundPodId: podId,
           claimedAt: '2026-09-05T00:00:00.000Z',
           updatedAt: '2026-09-05T00:01:00.000Z',
diff --git a/backend/__tests__/unit/services/installableInstallationService.test.js b/backend/__tests__/unit/services/installableInstallationService.test.js
index 18a4373d46..fa0b61295e 100644
--- a/backend/__tests__/unit/services/installableInstallationService.test.js
+++ b/backend/__tests__/unit/services/installableInstallationService.test.js
@@ -213,6 +213,12 @@ describe('installable connector projection', () => {
     const failed = await InstallableInstallation.findOne({ installableId: 'telegram' });
     const inactive = await Integration.findOne({ installationId: String(failed._id) });
     expect(failed.status).toBe('error');
+    // `markProjectionFailure` stores the projector's own exception text verbatim
+    // — stack-adjacent detail like `connect ECONNREFUSED <addr>:443` — so it is
+    // the writer that must say `false`. The catalog row renders this field only
+    // when the flag is true, and the row belongs to the installer, not to us
+    // (TASK-131, vera 73848).
+    expect(failed.errorMessageUserFacing).toBe(false);
     expect(inactive.isActive).toBe(false);
     expect(inactive.config.connectCode).toBeUndefined();
 
@@ -595,8 +601,20 @@ describe('installable connector projection', () => {
 
     const reconciled = await sweep(new Date());
     expect(reconciled.errored).toBe(2);
-    expect((await InstallableInstallation.findById(installing._id)).status).toBe('error');
-    expect((await InstallableInstallation.findById(activating._id)).status).toBe('error');
+    const expiring = await InstallableInstallation.findById(installing._id);
+    const expired = await InstallableInstallation.findById(activating._id);
+    expect(expiring.status).toBe('error');
+    expect(expired.status).toBe('error');
+    // Both reasons are our own constants, written for the person reading the
+    // Connectors page, so the writer states that beside the message. Without it
+    // the catalog row falls back to the generic sentence and the operator loses
+    // the only sentence that says what to do (TASK-131).
+    expect(expiring.errorMessageUserFacing).toBe(true);
+    expect(expired.errorMessageUserFacing).toBe(true);
+    // The copy itself is pinned here: these two strings are the whole set of
+    // reasons the catalogue will ever print verbatim, so a writer that changes
+    // one has to change this line too (wren 73914, vera 73915).
+    expect(expiring.errorMessage).toBe('Setup was interrupted before it finished. Try again.');
   });
 
   it('makes a missing active projection a retriable parent error', async () => {
@@ -608,7 +626,10 @@ describe('installable connector projection', () => {
     const parent = await InstallableInstallation.findById(installed.installation._id);
     expect(reconciled.staleComponents).toBe(1);
     expect(parent.status).toBe('error');
-    expect(parent.errorMessage).toBe('projection missing');
+    expect(parent.errorMessage).toBe("This connector's channel is gone. Retry to rebuild it.");
+    // The reconciler's own constant: a message written for a person, so it
+    // carries the flag the page requires before rendering (TASK-131).
+    expect(parent.errorMessageUserFacing).toBe(true);
     expect(parent.components.every((component) => component.status === 'stale')).toBe(true);
 
     const retried = await install({ installableId: 'telegram', installedBy: userId, podId });
diff --git a/backend/models/InstallableInstallation.ts b/backend/models/InstallableInstallation.ts
index c069f1be4e..e02f27ad6b 100644
--- a/backend/models/InstallableInstallation.ts
+++ b/backend/models/InstallableInstallation.ts
@@ -135,6 +135,14 @@ export interface IInstallableInstallation extends Document {
   claimId?: string;
   claimedAt?: Date;
   errorMessage?: string;
+  /**
+   * Whether `errorMessage` was written for a person. Two kinds of string land
+   * in that field — the reconciler's human-authored constants, and
+   * `markProjectionFailure`'s raw exception message — and the Connectors page
+   * renders them through one branch, so only a flagged message is printed
+   * (vera 73848). Set together with the message by the builders below.
+   */
+  errorMessageUserFacing?: boolean;
   staleSince?: Date;
   /** Canonical pause state; Integration.config.adminPause is its projection. */
   adminPause?: IInstallationAdminPause;
@@ -230,6 +238,7 @@ const InstallableInstallationSchema = new Schema<IInstallableInstallation>(
     claimId: { type: String },
     claimedAt: { type: Date },
     errorMessage: { type: String },
+    errorMessageUserFacing: { type: Boolean, default: false },
     staleSince: { type: Date },
     adminPause: {
       reason: { type: String },
diff --git a/backend/services/connectorDeliveryFailureService.ts b/backend/services/connectorDeliveryFailureService.ts
index 60e5db09ec..56709c893a 100644
--- a/backend/services/connectorDeliveryFailureService.ts
+++ b/backend/services/connectorDeliveryFailureService.ts
@@ -115,6 +115,11 @@ interface FlipInput {
  * its only writer, and the page renders the message only when it is set; a
  * writer that does not set it falls back to the generic sentence instead of
  * printing our stack text in a connector row (vera 73848).
+ *
+ * Stated, not defaulted: a `$set` that omits this key leaves the row's stored
+ * value in place, so omitting the flag is only safe on a row that has never
+ * carried one. `externalFeedService` names `errorMessageUserFacing: false` for
+ * exactly that reason — absence would be a claim it could not make.
  */
 const userFacingError = (reason: string) => ({
   status: 'error',
diff --git a/backend/services/externalFeedService.ts b/backend/services/externalFeedService.ts
index cfff6c7b02..c25c42b5dc 100644
--- a/backend/services/externalFeedService.ts
+++ b/backend/services/externalFeedService.ts
@@ -435,11 +435,15 @@ async function syncExternalFeeds(): Promise<FeedSyncResult[]> {
             $set: {
               status: 'error',
               // Diagnostic, not copy. This is a provider's error text or a raw
-              // exception message, so `errorMessageUserFacing` stays unset and
-              // the Connectors page shows its generic sentence for these rows —
-              // the detail is kept here for whoever debugs the feed instead of
-              // being printed in someone's connector list (vera 73848).
+              // exception message, so the detail is kept here for whoever debugs
+              // the feed rather than printed in someone's connector list (vera
+              // 73848). The flag is stated instead of left out because a `$set`
+              // that omits a key inherits the row's stored value: omitting it is
+              // only safe on a row that has never carried one, and naming it
+              // `false` is what makes the page's generic sentence this row's
+              // outcome no matter what it carried before.
               errorMessage: detail,
+              errorMessageUserFacing: false,
               lastSync: new Date(),
             },
           });
diff --git a/backend/services/installable/installableCatalogService.ts b/backend/services/installable/installableCatalogService.ts
index 5b6d8dde32..649652ce1b 100644
--- a/backend/services/installable/installableCatalogService.ts
+++ b/backend/services/installable/installableCatalogService.ts
@@ -56,7 +56,15 @@ const publicInstallation = (installation: any): unknown => {
   })) : [];
   return {
     status: installation.status,
-    ...(installation.errorMessage ? { errorMessage: installation.errorMessage } : {}),
+    // The message travels with its provenance. The page prints it only when this
+    // is true, so a raw exception from `markProjectionFailure` reaches the
+    // client and is deliberately not rendered (TASK-131).
+    ...(installation.errorMessage
+      ? {
+        errorMessage: installation.errorMessage,
+        errorMessageUserFacing: installation.errorMessageUserFacing === true,
+      }
+      : {}),
     ...(installation.boundPodId ? { boundPodId: String(installation.boundPodId) } : {}),
     ...(installation.claimedAt ? { claimedAt: installation.claimedAt } : {}),
     ...(installation.updatedAt ? { updatedAt: installation.updatedAt } : {}),
diff --git a/backend/services/installable/installableInstallationService.ts b/backend/services/installable/installableInstallationService.ts
index c58632a6c6..cad45f52ee 100644
--- a/backend/services/installable/installableInstallationService.ts
+++ b/backend/services/installable/installableInstallationService.ts
@@ -321,6 +321,32 @@ const claimInstallation = async (
   }
 };
 
+/**
+ * The two ways `InstallableInstallation.errorMessage` gets a value, each with
+ * its provenance attached.
+ *
+ * `errorMessage` alone cannot say the reason is fit to read. Three writers give
+ * it a value: `markProjectionFailure` (a raw exception —
+ * `connect ECONNREFUSED <addr>:443`), and the reconciler's two human-authored
+ * constants. The Connectors page renders every failed installation through one
+ * branch, so "the field has a value" is not the same fact as "the value was
+ * written for a person" (vera 73848). `errorMessageUserFacing` is that fact, and
+ * a message and its flag are written together here so that no writer can set
+ * half of the pair — the catalog row is a stranger's row, and printing our stack
+ * text in it is disclosure, not diagnosis.
+ */
+export const userFacingInstallationError = (reason: string) => ({
+  status: 'error',
+  errorMessage: reason,
+  errorMessageUserFacing: true,
+});
+
+export const diagnosticInstallationError = (error: Error) => ({
+  status: 'error',
+  errorMessage: error.message,
+  errorMessageUserFacing: false,
+});
+
 const throwIfLockLost = (installation: IInstallableInstallation | null): IInstallableInstallation => {
   if (!installation) throw new InstallLockLostError();
   return installation;
@@ -336,8 +362,7 @@ const markProjectionFailure = async (
     { _id: installation._id, status: 'installing', claimId },
     {
       $set: {
-        status: 'error',
-        errorMessage: error.message,
+        ...diagnosticInstallationError(error),
         components,
       },
     },
@@ -688,4 +713,8 @@ module.exports = {
   InstallableNotFoundError,
   install,
   uninstall,
+  // Named here as well as exported above: this file's CommonJS tail replaces the
+  // ES exports, so an `export const` on its own is invisible to every require().
+  userFacingInstallationError,
+  diagnosticInstallationError,
 };
diff --git a/backend/services/installable/installableReconciler.ts b/backend/services/installable/installableReconciler.ts
index e454b2b643..9d4d50d698 100644
--- a/backend/services/installable/installableReconciler.ts
+++ b/backend/services/installable/installableReconciler.ts
@@ -1,5 +1,5 @@
 import type { IInstallableInstallation } from '../../models/InstallableInstallation';
-import { INSTALL_LOCK_TTL_MS } from './installableInstallationService';
+import { INSTALL_LOCK_TTL_MS, userFacingInstallationError } from './installableInstallationService';
 
 // eslint-disable-next-line @typescript-eslint/no-require-imports, global-require
 const InstallableInstallation = require('../../models/InstallableInstallation');
@@ -58,7 +58,10 @@ const sweepStaleLocks = async (now: Date): Promise<{ completed: number; errored:
 
     const result = await InstallableInstallation.updateOne(
       { _id: installation._id, status: installation.status, claimId },
-      { $set: { status: 'error', errorMessage: 'install lock expired' } },
+      // The copy is the outcome the operator reads in the Connectors list, so
+      // it names the event and the next step and no internal one: a lock is our
+      // word, not theirs (wren 73914, vera 73915).
+      { $set: userFacingInstallationError('Setup was interrupted before it finished. Try again.') },
     );
     errored += result.modifiedCount || 0;
   }
@@ -87,8 +90,10 @@ const sweepActiveInstallations = async (): Promise<{ staleComponents: number; cl
       { _id: installation._id, status: 'active' },
       {
         $set: {
-          status: 'error',
-          errorMessage: 'projection missing',
+          // Distinct from the page's generic 'Setup didn't finish.' on purpose: the
+          // connector existed and its channel record vanished, which is a different
+          // event, and the evidence pair has to read as two outcomes (vera 73915).
+          ...userFacingInstallationError("This connector's channel is gone. Retry to rebuild it."),
           'components.$[].status': 'stale',
         },
       },
diff --git a/docs/design/evidence/task-131-catalog-error-line-1200-after.png b/docs/design/evidence/task-131-catalog-error-line-1200-after.png
new file mode 100644
index 0000000000..bf0206fb7d
Binary files /dev/null and b/docs/design/evidence/task-131-catalog-error-line-1200-after.png differ
diff --git a/docs/design/evidence/task-131-catalog-error-line-1200-after.txt b/docs/design/evidence/task-131-catalog-error-line-1200-after.txt
new file mode 100644
index 0000000000..bec4e95bc5
--- /dev/null
+++ b/docs/design/evidence/task-131-catalog-error-line-1200-after.txt
@@ -0,0 +1,36 @@
+EN
+LO
+Connectors
+
+Each channel gets one agent from a pod. It answers there in its own name; the rest of the team stays behind it.
+
+Slack
+no pod · since 13m
+This connector's channel is gone. Retry to rebuild it.
+retry, or remove it
+Retry
+Telegram
+no pod · since 13m
+Setup didn’t finish.
+retry, or remove it
+Retry
+Discord · WhatsApp
+not yet
+Not yet. Tell us which channel you need and we build it next.
+Ask
+
+next step
+
+This connector's channel is gone. Retry to rebuild it.
+
+Retry
+Remove
+Tools
+1 granted
+All
+Granted
+Not yet
+GitHub
+kai routing check · granted 6d
+granted to Kai routing check
+localdev may use it
\ No newline at end of file
diff --git a/docs/design/evidence/task-131-catalog-error-line-1200-before.png b/docs/design/evidence/task-131-catalog-error-line-1200-before.png
new file mode 100644
index 0000000000..2a27c91058
Binary files /dev/null and b/docs/design/evidence/task-131-catalog-error-line-1200-before.png differ
diff --git a/docs/design/evidence/task-131-catalog-error-line-1200-before.txt b/docs/design/evidence/task-131-catalog-error-line-1200-before.txt
new file mode 100644
index 0000000000..9989c09260
--- /dev/null
+++ b/docs/design/evidence/task-131-catalog-error-line-1200-before.txt
@@ -0,0 +1,36 @@
+EN
+LO
+Connectors
+
+Each channel gets one agent from a pod. It answers there in its own name; the rest of the team stays behind it.
+
+Slack
+no pod · since 13m
+This connector's channel is gone. Retry to rebuild it.
+retry, or remove it
+Retry
+Telegram
+no pod · since 13m
+connect ECONNREFUSED 10.4.4.7:443
+retry, or remove it
+Retry
+Discord · WhatsApp
+not yet
+Not yet. Tell us which channel you need and we build it next.
+Ask
+
+next step
+
+This connector's channel is gone. Retry to rebuild it.
+
+Retry
+Remove
+Tools
+1 granted
+All
+Granted
+Not yet
+GitHub
+kai routing check · granted 6d
+granted to Kai routing check
+localdev may use it
\ No newline at end of file
diff --git a/docs/design/evidence/task-131-catalog-error-line-390-after.png b/docs/design/evidence/task-131-catalog-error-line-390-after.png
new file mode 100644
index 0000000000..c2491ac0a6
Binary files /dev/null and b/docs/design/evidence/task-131-catalog-error-line-390-after.png differ
diff --git a/docs/design/evidence/task-131-catalog-error-line-390-after.txt b/docs/design/evidence/task-131-catalog-error-line-390-after.txt
new file mode 100644
index 0000000000..38899df28c
--- /dev/null
+++ b/docs/design/evidence/task-131-catalog-error-line-390-after.txt
@@ -0,0 +1,34 @@
+Connectors
+
+Each channel gets one agent from a pod. It answers there in its own name; the rest of the team stays behind it.
+
+Slack
+no pod · since 14m
+This connector's channel is gone. Retry to rebuild it.
+retry, or remove it
+Retry
+Telegram
+no pod · since 14m
+Setup didn’t finish.
+retry, or remove it
+Retry
+Discord · WhatsApp
+not yet
+Not yet. Tell us which channel you need and we build it next.
+Ask
+
+next step
+
+This connector's channel is gone. Retry to rebuild it.
+
+Retry
+Remove
+Tools
+1 granted
+All
+Granted
+Not yet
+GitHub
+kai routing check · granted 6d · every write asks first
+granted to Kai routing check
+localdev may use it
\ No newline at end of file
diff --git a/docs/design/evidence/task-131-catalog-error-line-390-before.png b/docs/design/evidence/task-131-catalog-error-line-390-before.png
new file mode 100644
index 0000000000..2b4b8feccf
Binary files /dev/null and b/docs/design/evidence/task-131-catalog-error-line-390-before.png differ
diff --git a/docs/design/evidence/task-131-catalog-error-line-390-before.txt b/docs/design/evidence/task-131-catalog-error-line-390-before.txt
new file mode 100644
index 0000000000..e0dea1742d
--- /dev/null
+++ b/docs/design/evidence/task-131-catalog-error-line-390-before.txt
@@ -0,0 +1,34 @@
+Connectors
+
+Each channel gets one agent from a pod. It answers there in its own name; the rest of the team stays behind it.
+
+Slack
+no pod · since 14m
+This connector's channel is gone. Retry to rebuild it.
+retry, or remove it
+Retry
+Telegram
+no pod · since 14m
+connect ECONNREFUSED 10.4.4.7:443
+retry, or remove it
+Retry
+Discord · WhatsApp
+not yet
+Not yet. Tell us which channel you need and we build it next.
+Ask
+
+next step
+
+This connector's channel is gone. Retry to rebuild it.
+
+Retry
+Remove
+Tools
+1 granted
+All
+Granted
+Not yet
+GitHub
+kai routing check · granted 6d · every write asks first
+granted to Kai routing check
+localdev may use it
\ No newline at end of file
diff --git a/docs/plans/connector-as-installable-app.md b/docs/plans/connector-as-installable-app.md
index 6298850d50..79d1289b0f 100644
--- a/docs/plans/connector-as-installable-app.md
+++ b/docs/plans/connector-as-installable-app.md
@@ -307,7 +307,7 @@ the slash-command / external-webhook tracks; naming them here keeps the enum hon
 row marks the component `stale` (never re-creates silently — a stale connector must not mint a
 code nobody asked for). For every `uninstalled` installation, projections must be inactive.
 For every **`installing`** installation whose `claimedAt` is older than `INSTALL_LOCK_TTL_MS`,
-the sweep sets `status: 'error'` with `errorMessage: 'install lock expired'` — fenced on the
+the sweep sets `status: 'error'` with `errorMessage: 'Setup was interrupted before it finished. Try again.'` — fenced on the
 `claimId` it read, so it cannot race a takeover that happened between its read and its write
 — and the row becomes the ordinary retryable case, and the board-facing state stops lying
 about work in progress. For a stale **`activating`** installation the sweep must **look
@@ -420,7 +420,7 @@ Unit (`backend/__tests__/unit/services/installable/`):
 5. Non-member of the chosen pod → 403, nothing written.
 6. Reconciler: a deleted Integration under an active installation marks the component `stale`,
    creates nothing. An `installing` row with `claimedAt` older than the TTL is swept to
-   `error` with `'install lock expired'`. A stale `activating` row whose Integration is still
+   `error` with `'Setup was interrupted before it finished. Try again.'`. A stale `activating` row whose Integration is still
    inactive is swept to `error`; a stale `activating` row whose Integration is already active
    with a code is **completed to `active`**, the code unchanged, `mintConnectCode` not called
    — never demoted, so no redeemable code ever sits under an `error` parent.
diff --git a/docs/plans/d8-phase-2-gate-surface.md b/docs/plans/d8-phase-2-gate-surface.md
index a7fee9e264..58ec2b4bc0 100644
--- a/docs/plans/d8-phase-2-gate-surface.md
+++ b/docs/plans/d8-phase-2-gate-surface.md
@@ -6,7 +6,7 @@
 
 ## 1. Three facts the page cannot see today
 
-1. **Parent state is invisible.** There is no `GET` on `/api/installables`. The page lists `Integration` rows from `/api/integrations/user/all` and infers the parent from `installationId`. A parent whose projection failed (`status: 'error'`, no Integration row), whose lock expired (`errorMessage: 'install lock expired'`), or whose Integration went missing (`components[].status: 'stale'`) shows **nothing** — and the next Connect returns a typed 409 the user cannot act on. The invisible-error class we closed inside the substrate is still open at the surface.
+1. **Parent state is invisible.** There is no `GET` on `/api/installables`. The page lists `Integration` rows from `/api/integrations/user/all` and infers the parent from `installationId`. A parent whose projection failed (`status: 'error'`, no Integration row), whose lock expired (`errorMessage: 'Setup was interrupted before it finished. Try again.'`), or whose Integration went missing (`components[].status: 'stale'`) shows **nothing** — and the next Connect returns a typed 409 the user cannot act on. The invisible-error class we closed inside the substrate is still open at the surface.
 2. **The page carries the provider list.** `ADD_PLATFORMS` in `V2ConnectorsPage.tsx` says Telegram and Slack are self-serve. The instance knows better: Slack is self-serve only if `slackOAuthService` and the `ConnectorSecret` key ring are configured, Telegram only if the bot token is. A self-hosted instance without Slack secrets shows an *Authorize in Slack* button that fails at `authorize-url` with a configuration error. Vera asked for the flag at 63278.
 3. **One pod per connector.** `Integration.podId` is required and is the single pod the connector relays. ADR-025 D8 says the private chat is the user's attention surface for **every** pod they are in, gated per pod. Phase 1 wrote the picked pod as "the first gate row" and stopped.
 
@@ -33,7 +33,7 @@
       "available": true,
       "installation": {
         "status": "error",
-        "errorMessage": "install lock expired",
+        "errorMessage": "Setup was interrupted before it finished. Try again.",
         "boundPodId": "66f…",
         "claimedAt": "2026-09-04T20:01:12Z",
         "updatedAt": "2026-09-04T20:02:12Z",
@@ -62,7 +62,7 @@
 | `error` | any | hollow `#98a2b3` | the parent's `errorMessage` as an ink sentence, else "Setup didn't finish." | `retry, or remove it` | `since {rel}` | **Retry** (ink) → `POST …/install { podId: boundPodId }`. The service's claim filter already admits `status: 'error'`; the parent is reclaimed in place, no second row. **Remove** is the bordered secondary in the aside (§2 D4) → `DELETE`, which `claimUninstall` accepts from `error` |
 | `active`, Integration present | per [#1542 §2](connectors-page-signal-diff.md) | as there | as there | as there | as there | Manage / Show code / New code / Authorize in Slack / Confirm — unchanged |
 | `active`, Integration present, `podId` unset (the owner left the active pod; D3 prune) | live | `#e4e7ec` solid (idle) | **{chat title}** {kind} · not linked to a pod | `your messages have nowhere to go` | `added {rel}` | **Pick a pod** (ink) → selects the row and opens the aside's gate list (D4) |
-| `active`, Integration missing or `isActive: false`, or any `components[].status: 'stale'` | — | hollow | The channel record is gone. | `retry rebuilds it` | `since {rel}` | **Retry** (ink) — same POST; `installAttempt` re-projects. The reconciler's stale-marking (`sweepActive`) is what makes this row honest; it should also set `status: 'error'`, `errorMessage: 'projection missing'` so the parent and the page agree (one-line change in `installableReconciler.ts`) |
+| `active`, Integration missing or `isActive: false`, or any `components[].status: 'stale'` | — | hollow | The channel record is gone. | `retry rebuilds it` | `since {rel}` | **Retry** (ink) — same POST; `installAttempt` re-projects. The reconciler's stale-marking (`sweepActive`) is what makes this row honest; it should also set `status: 'error'`, `errorMessage: "This connector's channel is gone. Retry to rebuild it."` so the parent and the page agree (one-line change in `installableReconciler.ts`) |
 | `uninstalling`, within TTL | any | cobalt pulsing | Removing… | `waiting for the server` | `started {rel}` | none |
 | `uninstalling`, past TTL | any | cobalt pulsing | Removal is taking longer than it should. | `the server let go of it` | `started {rel}` | **Retry remove** (bordered) → `DELETE` again; `claimUninstall` re-claims a stale `uninstalling` |
 | `paused` (written only by the admin lever, §2 D3) | any | hollow | Paused by an administrator. {reason} | `ask your operator` | `paused {rel}` from `adminPause.at` | none for the owner — Resume is the admin's, so the owner is never shown a control that will 403 |
@@ -101,7 +101,7 @@ The page renders the gate list **only when the row carries `config.gates`**; a P
 
 | PR | what | size | depends on |
 |---|---|---|---|
-| A | catalog route + `readiness()` per manifest + install refusal `provider_not_configured` + reconciler `projection missing` | S | — |
+| A | catalog route + `readiness()` per manifest + install refusal `provider_not_configured` + reconciler channel-gone reason | S | — |
 | B | page: rows keyed by catalog, D2 state table, Retry / Remove / Cancel wired, poll on the catalog | M | A. **Folds into Kai's Signal restyle (TASK-007)** if that PR is still open — it re-keys the rows anyway; two PRs that both rewrite the row grid is one too many |
 | C | D8 schema: `scope`, optional `podId`, `config.gates`, outbound inversion, inbound on `podId` + membership at receive with the chat reply, PATCH gate and `podId` writes, migration script, reconciler prune (gates and the active pod); the admin pause/resume verbs with `paused` in the partial index, `liveClaimStatuses` and `statusForClaim`, the two owner-verb refusals, and the two sweep branches | M–L | — (backend only; the page ignores `gates` until D) |
 | D | page: gate list in the aside, `active` tag + Make active, the *not linked* row, per-pod overrides, Remove at the foot | S | B, C |
@@ -114,7 +114,7 @@ A and C are independent and can run in parallel. B before C is fine: the page sh
 2. **Error row → Retry.** Force a projection failure (projector throws) → parent `error`, no Integration; catalog shows the error row; `POST install` with the same `podId` reclaims the **same** parent `_id` (count of parents for that user stays 1) and reaches `active`.
 3. **Cancel is TTL-honest.** Parent stuck `installing` with `claimedAt` 30 s old → `DELETE` answers 409 `install_in_progress`; at 61 s → `DELETE` answers 202 `uninstalling` and the parent's `claimId` changes. The page shows no Cancel at 30 s and shows it at 61 s (the row's `claimedAt` drives it, no client clock trick — inject the clock).
 4. **Remove from error.** Parent `error` → `DELETE` → `uninstalled`; the catalog entry returns to `installation: null`; the orphan-secret sweep revokes any `ConnectorSecret` the failed attempt left.
-5. **Projection missing.** Delete a live Integration under an `active` parent → the 5-minute sweep marks the parent `error` `projection missing`; catalog shows the row; Retry re-projects with the same `installationId`.
+5. **Projection missing.** Delete a live Integration under an `active` parent → the 5-minute sweep marks the parent `error` `This connector's channel is gone. Retry to rebuild it.`; catalog shows the row; Retry re-projects with the same `installationId`.
 6. **Gates route outbound.** User in pods A and B, `gates[A].enabled: true`, `gates[B]` absent → an escalation in B reaches the channel **zero** times, in A once. Flip B on → once. User leaves A → the prune drops `gates[A]` within one sweep and outbound from A stops immediately (membership is checked at send).
 6b. **Leaving the active pod is heard, not swallowed.** User in pods A and B, `podId: A`, `gates[A]` and `gates[B]` enabled; user leaves A. A bare message typed before the sweep → no pod post (membership fails at receive) and one reply in the chat (*This connector has no active pod. Choose one in Commonly first.*); the sweep unsets `gates[A]` **and** `podId` within five minutes; a bare message after the sweep gets the same reply, still no post; the page shows the *not linked to a pod* row with **Pick a pod**; `PATCH { podId: B }` from the owner → the next bare message posts in B; the same PATCH from the pod-B creator → 403; `PATCH { podId: C }` for a pod the owner is not in → 403. Switching `gates[B]` off while `podId: B` changes nothing inbound: the owner's next message still posts in B.
 7. **Gate write is membership-gated.** `PATCH` with a `gates` key for a pod the caller is not a member of → 403, no write; other keys in the same body are also refused (all-or-nothing).
diff --git a/frontend/src/v2/__tests__/V2ConnectorsPage.test.tsx b/frontend/src/v2/__tests__/V2ConnectorsPage.test.tsx
index 8b4203ac34..13deb86493 100644
--- a/frontend/src/v2/__tests__/V2ConnectorsPage.test.tsx
+++ b/frontend/src/v2/__tests__/V2ConnectorsPage.test.tsx
@@ -82,6 +82,11 @@ const renderPage = () => render(
   </AuthContext.Provider>,
 );
 
+// The reconciler's own constant — the reason a person reads when the channel
+// record behind a connector is gone. It replaced the old 'projection missing'
+// wording in the TASK-131 copy pass (wren 73914, vera 73915).
+const REASON_CHANNEL_GONE = "This connector's channel is gone. Retry to rebuild it.";
+
 describe('V2ConnectorsPage', () => {
   beforeEach(() => {
     jest.clearAllMocks();
@@ -530,6 +535,35 @@ describe('V2ConnectorsPage', () => {
       });
     };
 
+    it('TASK-131: a catalog failure prints the generic sentence, not the raw exception that wrote the row', async () => {
+      // The catalogue half reads `InstallableInstallation.errorMessage`, whose
+      // projection-failure writer stores `error.message` verbatim. Same rule as
+      // the pod-scoped half: a value in the field is not permission to render
+      // it, and the flag is absent on this fixture.
+      const raw = 'connect ECONNREFUSED 10.4.4.7:443';
+      mockCatalog([
+        entry({ installation: { status: 'error', errorMessage: raw } }),
+      ]);
+      renderPage();
+
+      expect((await screen.findAllByText('Setup didn’t finish.')).length).toBeGreaterThan(0);
+      expect(screen.queryByText(raw)).toBeNull();
+    });
+
+    it('TASK-131: a catalog message written for a person still renders verbatim', async () => {
+      // The reconciler's own reasons are written for the person reading this row,
+      // and the flag the builder sets beside them is what keeps them readable once
+      // the generic sentence became the fallback.
+      const reason = REASON_CHANNEL_GONE;
+      mockCatalog([
+        entry({ installation: { status: 'error', errorMessage: reason, errorMessageUserFacing: true } }),
+      ]);
+      renderPage();
+
+      expect((await screen.findAllByText(reason)).length).toBeGreaterThan(0);
+      expect(screen.queryByText('Setup didn’t finish.')).toBeNull();
+    });
+
     // Tools plan (Sam's option A, two lists): a tool Installable shares the
     // catalogue response but belongs to the Tools page, never to this one.
     it('a tool Installable in the catalogue never renders as a channel row', async () => {
@@ -680,13 +714,23 @@ describe('V2ConnectorsPage', () => {
 
     it('offers Retry on an error parent, posting the bound pod, and Remove in the aside', async () => {
       mockCatalog([entry({
-        installation: { status: 'error', errorMessage: 'projection missing', boundPodId: 'p2', updatedAt: new Date().toISOString(), components: [] },
+        // The reconciler's own reason, and since TASK-131 it travels with the flag
+        // that says so: the row's line renders a message only when a writer
+        // declared it was written for a person.
+        installation: {
+          status: 'error',
+          errorMessage: REASON_CHANNEL_GONE,
+          errorMessageUserFacing: true,
+          boundPodId: 'p2',
+          updatedAt: new Date().toISOString(),
+          components: [],
+        },
       })]);
       axios.post.mockResolvedValue({ data: { status: 'installing' } });
       axios.delete.mockResolvedValue({ data: { status: 'uninstalled' } });
       renderPage();
 
-      expect((await screen.findAllByText('projection missing')).length).toBeGreaterThan(0);
+      expect((await screen.findAllByText(REASON_CHANNEL_GONE)).length).toBeGreaterThan(0);
       expect(screen.getByText('retry, or remove it')).toBeInTheDocument();
       fireEvent.click(screen.getAllByRole('button', { name: 'Retry' })[0]);
       await waitFor(() => expect(axios.post).toHaveBeenCalledWith(
diff --git a/frontend/src/v2/components/V2ConnectorsPage.tsx b/frontend/src/v2/components/V2ConnectorsPage.tsx
index bc9683dfb1..5d6736c133 100644
--- a/frontend/src/v2/components/V2ConnectorsPage.tsx
+++ b/frontend/src/v2/components/V2ConnectorsPage.tsx
@@ -60,7 +60,13 @@ interface Connector {
 
 interface CatalogInstallation {
   status: string;
+  // The same pair the pod-scoped half reads, and the same rule: the field
+  // holding a value is not permission to show it. A catalog failure is
+  // `markProjectionFailure`'s raw exception message unless a writer says
+  // otherwise, so the flag decides and the generic sentence is the fallback
+  // (TASK-131, vera 73848).
   errorMessage?: string;
+  errorMessageUserFacing?: boolean;
   boundPodId?: string;
   claimedAt?: string;
   updatedAt?: string;
@@ -820,7 +826,9 @@ const V2ConnectorsPage: React.FC = () => {
         actionLabel: t('connectors.retry', { defaultValue: 'Retry' }),
         detail: t('connectors.retryOrRemove', { defaultValue: 'retry, or remove it' }),
         dot: 'empty',
-        line: installation.errorMessage || t('connectors.setupFailed', { defaultValue: 'Setup didn’t finish.' }),
+        line: installation.errorMessageUserFacing && installation.errorMessage
+          ? installation.errorMessage
+          : t('connectors.setupFailed', { defaultValue: 'Setup didn’t finish.' }),
         pulse: false,
         when: since,
       };