diff --git a/CHANGELOG.md b/CHANGELOG.md
index 38d4b58..cc2a9d9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,11 @@ at boot. Entries start at 0.3.0.
 
 ## Unreleased
 
+### A secret plugin setting's bad value stays out of the boot error
+
+When a `secret` setting's value fails validation, the boot error no longer prints it, so a malformed
+DSN doesn't put its password in the log.
+
 ### The admin's recovery-code notice links to the recovery flow the code belongs to
 
 After an admin generates a recovery code for a user, the notice asks them to send the user both the
diff --git a/README.md b/README.md
index cfdb1ed..f70825e 100644
--- a/README.md
+++ b/README.md
@@ -868,7 +868,7 @@ export default definePlugin({
 ```
 
 `type` is one of `string`, `number`, `boolean`, `enum` (with `values`) or `url`. A declared type is
-coerced and checked at boot, so a mistyped value names the plugin, the key and the variable instead
+coerced and checked at boot, so a mistyped value names the plugin and the variable instead
 of surfacing later as a broken page.
 
 **`required` and `default` are mutually exclusive** — a default means the setting can never fail, so
diff --git a/docs/reading-cost.md b/docs/reading-cost.md
index 46aa50b..c3d477d 100644
--- a/docs/reading-cost.md
+++ b/docs/reading-cost.md
@@ -274,3 +274,20 @@ Read most (opens and searches):
 - `src/i18n/locales/en-US.ts` 3
 - `e2e-tests/compose.full.yml` 2
 - `src/auth/kratos-admin.ts` 2
+
+## Reading cost, chunk d8b41620d631, finished 2026-10-31T12:37:38Z
+
+70583 new input tokens before the first commit.
+
+Read most (opens and searches):
+
+- `todo.md` 5
+- `AGENTS.md` 2
+- `README.md` 2
+- `examples/plugins/admin/README.md` 2
+- `src/auth/kratos-admin.ts` 2
+- `src/http/app-admin.test.ts` 2
+- `CHANGELOG.md` 1
+- `e2e-tests/full-flow.spec.ts` 1
+- `examples/plugins/admin/admin-users.test.ts` 1
+- `examples/plugins/admin/admin-users.ts` 1
diff --git a/src/plugin-host/settings.test.ts b/src/plugin-host/settings.test.ts
index ee77e65..3e7cb11 100644
--- a/src/plugin-host/settings.test.ts
+++ b/src/plugin-host/settings.test.ts
@@ -109,12 +109,27 @@ test("each type coerces from the environment, and a bad value fails loud", () =>
     PLUGIN_SETTING_P_MODE: "loose",
   });
   assert.equal(bad.errors.length, 4);
-  assert.match(bad.errors.join("\n"), /PLUGIN_SETTING_P_COUNT.*number/);
-  assert.match(bad.errors.join("\n"), /PLUGIN_SETTING_P_FLAG.*"true".*"false"/);
-  assert.match(bad.errors.join("\n"), /PLUGIN_SETTING_P_MODE.*strict, lenient/);
-  assert.match(bad.errors.join("\n"), /PLUGIN_SETTING_P_BASE.*URL/);
+  assert.match(bad.errors.join("\n"), /PLUGIN_SETTING_P_COUNT.*number, got "twelve"/);
+  assert.match(bad.errors.join("\n"), /PLUGIN_SETTING_P_FLAG.*"true".*"false", got "yes"/);
+  assert.match(bad.errors.join("\n"), /PLUGIN_SETTING_P_MODE.*strict, lenient, got "loose"/);
+  assert.match(bad.errors.join("\n"), /PLUGIN_SETTING_P_BASE.*URL, got "not a url"/);
 });
 
+const SECRET_CASES: [SettingDecl, string, RegExp][] = [
+  [{ key: "s", secret: true, type: "boolean" }, "hunter2-bool", /PLUGIN_SETTING_P_S.*"true".*"false"/],
+  [{ key: "s", secret: true, type: "enum", values: ["a", "b"] }, "hunter2-enum", /PLUGIN_SETTING_P_S.*a, b/],
+  [{ key: "s", secret: true, type: "number" }, "hunter2-number", /PLUGIN_SETTING_P_S.*number/],
+  [{ key: "s", secret: true, type: "url" }, "postgres user:hunter2-url@db", /PLUGIN_SETTING_P_S.*URL/],
+];
+for (const [decl, raw, names] of SECRET_CASES) {
+  test(`a secret ${decl.type}'s bad value never reaches the boot error`, () => {
+    const errors = resolveSettings([pluginWith("p", [decl])], { PLUGIN_SETTING_P_S: raw }).errors;
+    assert.equal(errors.length, 1);
+    assert.match(errors[0] ?? "", names);
+    assert.ok(!(errors[0] ?? "").includes("hunter2"));
+  });
+}
+
 test("a boolean is only \"true\"/\"false\" — a typo never degrades to false", () => {
   const plugins = [pluginWith("p", [{ default: true, key: "flag", type: "boolean" }])];
   assert.equal(resolveSettings(plugins, { PLUGIN_SETTING_P_FLAG: "false" }).values.get("p")?.["flag"], false);
diff --git a/src/plugin-host/settings.ts b/src/plugin-host/settings.ts
index 282ac73..9f49f3d 100644
--- a/src/plugin-host/settings.ts
+++ b/src/plugin-host/settings.ts
@@ -233,24 +233,25 @@ function summarize(decl: SettingDecl, name: string, source: SettingSummary["sour
 
 // A coerced value, or the boot error naming the variable and what it accepts.
 function coerce(decl: SettingDecl, raw: string, name: string): { value: SettingValue } | string {
+  const got = decl.secret === true ? "" : `, got "${raw}"`;
   switch (decl.type) {
     case "boolean":
       if (raw === "true") return { value: true };
       if (raw === "false") return { value: false };
-      return `${name} must be "true" or "false", got "${raw}"`;
+      return `${name} must be "true" or "false"${got}`;
     case "enum":
       return (decl.values ?? []).includes(raw)
         ? { value: raw }
-        : `${name} must be one of ${(decl.values ?? []).join(", ")}, got "${raw}"`;
+        : `${name} must be one of ${(decl.values ?? []).join(", ")}${got}`;
     case "number": {
       const value = Number(raw);
-      return Number.isFinite(value) ? { value } : `${name} must be a number, got "${raw}"`;
+      return Number.isFinite(value) ? { value } : `${name} must be a number${got}`;
     }
     case "url":
       try {
         new URL(raw);
       } catch {
-        return `${name} is not a valid URL: ${raw}`;
+        return `${name} must be a valid URL${got}`;
       }
       return { value: raw };
     case "string":
diff --git a/todo.md b/todo.md
index eabe39d..c52b36d 100644
--- a/todo.md
+++ b/todo.md
@@ -6,13 +6,13 @@
 
 `Bar = 1`
 
-`Next ID = 55`
+`Next ID = 56`
 
 ## Items
 
 | ID | Release | Blocked by | Exempt | Item | L | E | I | R | S | Moves | Score |
 |---|---|---|---|---|---|---|---|---|---|---|---|
-| 46 | 0.4.21 |  | security | **Keep a secret setting's raw value out of the boot error that rejects it.** | 1 | 1 | 4 | 5 | 2 |  | 0.0 |
+| 55 | 0.4.21 |  | security | **Keep a URL config value out of the boot error that rejects it.** | 1 | 1 | 4 | 5 | 2 |  | 0.0 |
 | 19 | 0.5.0 |  | question | **Run the documented Docker commands on macOS and fix whatever misbehaves.** | 2 | 2 | 1 | 3 | 3 | 1 by 3 | 3.3 |
 | 16 | 0.5.0 |  | question | **Decide whether the single Keto `Resource` namespace splits into per-domain namespaces.** | 3 | 2 | 3 | 6 | 6 | 7 by 2 | 0.5 |
 | 48 | 0.5.0 |  |  | **Correct the Keto tuple in the `login.ts` and `bootstrap.ts` comments to the `granted` relation the code writes.** | 1 | 1 | 1 | 1 | 1 | code health by 4 | 28.7 |
@@ -34,12 +34,19 @@
 
 ## Details
 
-### 46. Keep a secret setting's raw value out of the boot error that rejects it.
+### 55. Keep a URL config value out of the boot error that rejects it.
 
-`coerce` in `src/plugin-host/settings.ts` puts `got "${raw}"` (boolean, enum, number) and `: ${raw}`
-(url) into the error it returns, whatever `secret` says. A secret of type `url`, such as a DSN with
-a password, that fails `new URL` reaches the boot error and so the log. Name the variable and what it
-accepts, never the value; test one secret of each type.
+`readOptionalUrl` and `readUrl` in `src/config.ts` throw `config: ${key} is not a valid URL: ${value}`,
+so a malformed value reaches the boot error and the log. A DSN whose password breaks parsing, such as
+`postgres://admin:pa/ss@db:5432/plugins`, leaks that password. The keys that can carry credentials:
+`PLUGIN_DB_URL` (`readCredentiallessUrl` refuses userinfo only after `readOptionalUrl` has parsed it,
+so a pasted admin DSN that fails to parse is echoed), and `OTLP_ENDPOINT`, whose collector URL may
+embed basic-auth userinfo. The other URL keys, `APP_URL`, `HYDRA_ADMIN_URL`, `JWKS_URL`,
+`KETO_READ_URL`, `KETO_WRITE_URL`, `KRATOS_ADMIN_URL` and `KRATOS_PUBLIC_URL`, pass through the same
+two readers, so the fix covers them too. Name the variable and what it accepts, never the value, and
+add a test per credential-bearing key. The other readers in `config.ts` echo only non-credential
+values. `PLUGIN_DB_ADMIN_URL` isn't read in `config.ts`: `bootstrap.ts` hands it straight to
+`postgres()`. Check whether the driver echoes a malformed one.
 
 ### 19. Run the documented Docker commands on macOS and fix whatever misbehaves.