Expose managed WebMCP policy through the app server (#42823)

## What changed

- Parse the optional `[browser_use].allow_webmcp` boolean from managed requirements and preserve requirement-layer precedence.
- Return the policy as `browserUse.allowWebmcp` from `configRequirements/read`, including explicit `true`, explicit `false`, and `null` when omitted.
- Update the generated JSON and TypeScript protocol schemas.

## Testing

- Cover parsing, invalid values, layered overrides, and app-server response serialization.

GitOrigin-RevId: a3fd7d1a6f838bb3ab0ac2a644409101a2338ca6

codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.schemas.json

@@ -8098,6 +8098,12 @@
               "null"
             ]
           },
+          "allowWebmcp": {
+            "type": [
+              "boolean",
+              "null"
+            ]
+          },
           "defaultOriginPolicy": {
             "anyOf": [
               {

codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.v2.schemas.json

@@ -1582,6 +1582,12 @@
             "null"
           ]
         },
+        "allowWebmcp": {
+          "type": [
+            "boolean",
+            "null"
+          ]
+        },
         "defaultOriginPolicy": {
           "anyOf": [
             {

codex-rs/app-server-protocol/schema/json/v2/ConfigRequirementsReadResponse.json

@@ -215,6 +215,12 @@
             "null"
           ]
         },
+        "allowWebmcp": {
+          "type": [
+            "boolean",
+            "null"
+          ]
+        },
         "defaultOriginPolicy": {
           "anyOf": [
             {

codex-rs/app-server-protocol/schema/typescript/v2/BrowserUseRequirements.ts

@@ -3,4 +3,4 @@
 // This file was generated by [ts-rs](https://github.com/Aleph-Alpha/ts-rs). Do not edit this file manually.
 import type { BrowserUseOriginPolicy } from "./BrowserUseOriginPolicy";
 
-export type BrowserUseRequirements = { allowHistoryAccess: boolean | null, disableAutoReview: boolean | null, allowGlobalPersistentApproval: boolean | null, defaultOriginPolicy: BrowserUseOriginPolicy | null, origins: { [key in string]?: BrowserUseOriginPolicy } | null, };
+export type BrowserUseRequirements = { allowWebmcp: boolean | null, allowHistoryAccess: boolean | null, disableAutoReview: boolean | null, allowGlobalPersistentApproval: boolean | null, defaultOriginPolicy: BrowserUseOriginPolicy | null, origins: { [key in string]?: BrowserUseOriginPolicy } | null, };

codex-rs/app-server-protocol/src/protocol/v2/config.rs

@@ -505,6 +505,7 @@ pub struct ComputerUseRequirements {
 #[serde(rename_all = "camelCase")]
 #[ts(export_to = "v2/")]
 pub struct BrowserUseRequirements {
+    pub allow_webmcp: Option<bool>,
     pub allow_history_access: Option<bool>,
     pub disable_auto_review: Option<bool>,
     pub allow_global_persistent_approval: Option<bool>,

codex-rs/app-server/README.md

@@ -314,7 +314,8 @@ Example with notification opt-out:
 - `externalAgentConfig/import/readHistories` — read completed import histories and connector candidates detected from successfully imported session histories. Successful session entries include the original imported title when one was available. Connector candidates include a normalized display `name`, the number of imported sessions that used the connector, and the source metadata field used for detection.
 - `config/value/write` — write a single config key/value to the user's config.toml on disk; dotted paths such as `desktop.someKey` use the same generic write surface. Writes that overlap a managed requirement are rejected with `configRequirementReadonly`.
 - `config/batchWrite` — apply multiple config edits atomically to the user's config.toml on disk, with optional `reloadUserConfig: true` to hot-reload loaded threads, including multiple `desktop.*` edits. Session-static model, reasoning-effort, Plan-mode reasoning-effort, service-tier, and personality defaults do not reload existing threads.
-- `configRequirements/read` — fetch loaded requirements constraints from `requirements.toml` and/or MDM (or `null` if none are configured), including exact managed values (`cliAuthCredentialsStore`, `chatgptBaseUrl`, `sqliteHome`, `logDir`, `modelCatalogJson`, `checkForUpdateOnStartup`, `allowLoginShell`, `feedback.enabled`, and `windowsSandboxPrivateDesktop`), requirements-only developer instructions (`additionalDeveloperInstructions`, supplied independently of ordinary developer instructions), allow-lists (`allowedApprovalPolicies`, `allowedSandboxModes`, `allowedWebSearchModes`), the layered permission-profile allow map (`allowedPermissionProfiles`), the managed permission-profile default (`defaultPermissions`), lifecycle hook lockdown (`allowManagedHooksOnly`), remote-control policy (`allowRemoteControl`; `false` force-disables remote control while `true` or `null` preserves existing behavior), the Browser/Computer Use umbrella policy (`allowBrowserAndComputerUse`), computer use policy (`computerUse`, including persistent approval, default application access, and per-platform application rules), Browser Use policy (`browserUse`, including history access, origin rules, auto-review, and approval controls), interactive browser import policy (`inAppBrowser.allowExternalBrowserSettingsImport`), pinned feature values (`featureRequirements`, including the default-allowed `in_app_updates` policy that administrators can set to `false`), managed lifecycle hooks (`hooks`, including command handlers with optional `additionalContextLimit` and `mcp_tool` handlers with `server`, `tool`, `input`, `timeoutSec`, and `statusMessage`), `enforceResidency`, managed automatic review (`autoReview.requiredOnModels` and `autoReview.ignoreRules`), model defaults (`models.newThread.model`, `models.newThread.modelReasoningEffort`, and `models.newThread.serviceTier`), and `network` constraints such as canonical domain/socket permissions plus `managedAllowedDomainsOnly` and `dangerFullAccessDenylistOnly`.
+- `configRequirements/read` — fetch loaded requirements constraints from `requirements.toml` and/or MDM (or `null` if none are configured), including exact managed values (`cliAuthCredentialsStore`, `chatgptBaseUrl`, `sqliteHome`, `logDir`, `modelCatalogJson`, `checkForUpdateOnStartup`, `allowLoginShell`, `feedback.enabled`, and `windowsSandboxPrivateDesktop`), requirements-only developer instructions (`additionalDeveloperInstructions`, supplied independently of ordinary developer instructions), allow-lists (`allowedApprovalPolicies`, `allowedSandboxModes`, `allowedWebSearchModes`), the layered permission-profile allow map (`allowedPermissionProfiles`), the managed permission-profile default (`defaultPermissions`), lifecycle hook lockdown (`allowManagedHooksOnly`), remote-control policy (`allowRemoteControl`; `false` force-disables remote control while `true` or `null` preserves existing behavior), the Browser/Computer Use umbrella policy (`allowBrowserAndComputerUse`), computer use policy (`computerUse`, including persistent approval, default application access, and per-platform application rules), Browser Use policy (`browserUse`, including WebMCP enablement, history access, origin rules, auto-review, and approval controls), interactive browser import policy (`inAppBrowser.allowExternalBrowserSettingsImport`), pinned feature values (`featureRequirements`, including the default-allowed `in_app_updates` policy that administrators can set to `false`), managed lifecycle hooks (`hooks`, including command handlers with optional `additionalContextLimit` and `mcp_tool` handlers with `server`, `tool`, `input`, `timeoutSec`, and `statusMessage`), `enforceResidency`, managed automatic review (`autoReview.requiredOnModels` and `autoReview.ignoreRules`), model defaults (`models.newThread.model`, `models.newThread.modelReasoningEffort`, and `models.newThread.serviceTier`), and `network` constraints such as canonical domain/socket permissions plus `managedAllowedDomainsOnly` and `dangerFullAccessDenylistOnly`.
+  - Managed `[browser_use].allow_webmcp` is returned as `browserUse.allowWebmcp`, preserving `true`, `false`, and omission as `null`. Desktop clients enable WebMCP when their WebMCP Statsig gate is on **or** this field is `true`. A `false` or omitted policy does not disable a gate-enabled feature. When policy is omitted, enterprise and consumer defaults come from Statsig. This is a requirements-only field; ordinary `config.toml` settings cannot enable it through this API.
 
 `mcpServer/resource/read` and `mcpServer/tool/call` preserve MCP protocol errors
 with their original `code`, `message`, and `data`, including authentication

codex-rs/app-server/src/request_processors/config_processor.rs

@@ -561,6 +561,7 @@ fn map_browser_use_requirements_to_api(
     browser_use: codex_config::BrowserUseRequirementsToml,
 ) -> BrowserUseRequirements {
     BrowserUseRequirements {
+        allow_webmcp: browser_use.allow_webmcp,
         allow_history_access: browser_use.allow_history_access,
         disable_auto_review: browser_use.disable_auto_review,
         allow_global_persistent_approval: browser_use.allow_global_persistent_approval,
@@ -940,6 +941,7 @@ mod tests {
         let mapped = map_requirements_toml_to_api(ConfigRequirementsToml {
             allow_browser_and_computer_use: Some(false),
             browser_use: Some(BrowserUseRequirementsToml {
+                allow_webmcp: Some(true),
                 allow_history_access: Some(false),
                 disable_auto_review: Some(true),
                 allow_global_persistent_approval: Some(false),
@@ -997,6 +999,7 @@ mod tests {
         assert_eq!(
             mapped.browser_use,
             Some(BrowserUseRequirements {
+                allow_webmcp: Some(true),
                 allow_history_access: Some(false),
                 disable_auto_review: Some(true),
                 allow_global_persistent_approval: Some(false),

codex-rs/app-server/tests/suite/v2/config_requirements_browser_use_tests.rs

@@ -0,0 +1,72 @@
+use anyhow::Result;
+use app_test_support::TestAppServer;
+use codex_app_server_protocol::ClientInfo;
+use pretty_assertions::assert_eq;
+use serde_json::Value;
+use serde_json::json;
+use std::time::Duration;
+use tempfile::TempDir;
+use tokio::time::timeout;
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn config_requirements_read_preserves_webmcp_policy() -> Result<()> {
+    for (contents, expected_browser_use) in [
+        ("", None),
+        ("[browser_use]", None),
+        (
+            "[browser_use]\nallow_history_access = true",
+            Some((Some(true), None)),
+        ),
+        (
+            "[browser_use]\nallow_webmcp = true",
+            Some((None, Some(true))),
+        ),
+        (
+            "[browser_use]\nallow_webmcp = false",
+            Some((None, Some(false))),
+        ),
+    ] {
+        let codex_home = TempDir::new()?;
+        std::fs::write(codex_home.path().join("requirements.toml"), contents)?;
+        std::fs::write(
+            codex_home.path().join("config.toml"),
+            "[browser_use]\nallow_webmcp = true",
+        )?;
+        let mut server = TestAppServer::builder()
+            .with_codex_home(codex_home.path())
+            .build()
+            .await?;
+        let read_timeout = Duration::from_secs(/*secs*/ 60);
+        timeout(
+            read_timeout,
+            server.initialize_with_capabilities(
+                ClientInfo {
+                    name: "webmcp_policy_test".to_string(),
+                    title: None,
+                    version: "0.1.0".to_string(),
+                },
+                /*capabilities*/ None,
+            ),
+        )
+        .await??;
+        let request_id = server.send_config_requirements_read_request().await?;
+        let wire: Value = timeout(read_timeout, server.read_response(request_id)).await??;
+        if let Some((allow_history_access, allow_webmcp)) = expected_browser_use {
+            assert_eq!(
+                wire["requirements"]["browserUse"],
+                json!({
+                    "allowWebmcp": allow_webmcp,
+                    "allowHistoryAccess": allow_history_access,
+                    "disableAutoReview": null,
+                    "allowGlobalPersistentApproval": null,
+                    "defaultOriginPolicy": null,
+                    "origins": null,
+                }),
+                "{contents}",
+            );
+        } else {
+            assert_eq!(wire, json!({ "requirements": null }), "{contents}");
+        }
+    }
+    Ok(())
+}

codex-rs/app-server/tests/suite/v2/config_requirements_in_app_browser.rs

@@ -106,6 +106,7 @@ async fn import_policy_is_separate_from_browser_feature_and_agent_policy() -> Re
                 allow_external_browser_settings_import: Some(false),
             }),
             Some(BrowserUseRequirements {
+                allow_webmcp: None,
                 allow_history_access: None,
                 disable_auto_review: Some(true),
                 allow_global_persistent_approval: None,

codex-rs/app-server/tests/suite/v2/config_rpc.rs

@@ -297,6 +297,7 @@ access = "deny"
     assert_eq!(
         requirements.browser_use,
         Some(BrowserUseRequirements {
+            allow_webmcp: None,
             allow_history_access: Some(false),
             disable_auto_review: Some(true),
             allow_global_persistent_approval: Some(false),
@@ -822,6 +823,7 @@ access = "deny"
     assert_eq!(
         requirements.browser_use,
         Some(BrowserUseRequirements {
+            allow_webmcp: None,
             allow_history_access: Some(false),
             disable_auto_review: None,
             allow_global_persistent_approval: Some(false),

codex-rs/app-server/tests/suite/v2/mod.rs

@@ -14,6 +14,8 @@ mod collaboration_mode_list;
 mod command_exec;
 mod compaction;
 mod config_requirements_application;
+#[path = "config_requirements_browser_use_tests.rs"]
+mod config_requirements_browser_use;
 mod config_requirements_in_app_browser;
 mod config_rpc;
 mod connection_handling_websocket;

codex-rs/config/src/browser_computer_use_requirements.rs

@@ -42,6 +42,7 @@ pub enum BrowserUseAccessApprovalLifetimeToml {
 
 #[derive(Deserialize, Debug, Clone, Default, PartialEq, Eq)]
 pub struct BrowserUseRequirementsToml {
+    pub allow_webmcp: Option<bool>,
     pub allow_history_access: Option<bool>,
     pub disable_auto_review: Option<bool>,
     pub allow_global_persistent_approval: Option<bool>,
@@ -51,7 +52,8 @@ pub struct BrowserUseRequirementsToml {
 
 impl BrowserUseRequirementsToml {
     pub fn is_empty(&self) -> bool {
-        self.allow_history_access.is_none()
+        self.allow_webmcp.is_none()
+            && self.allow_history_access.is_none()
             && self.disable_auto_review.is_none()
             && self.allow_global_persistent_approval.is_none()
             && self
@@ -108,3 +110,7 @@ impl ComputerUseRequirementsToml {
             })
     }
 }
+
+#[cfg(test)]
+#[path = "browser_computer_use_requirements_tests.rs"]
+mod tests;

codex-rs/config/src/browser_computer_use_requirements_tests.rs

@@ -0,0 +1,45 @@
+use crate::BrowserUseRequirementsToml;
+use crate::ConfigRequirementsToml;
+use pretty_assertions::assert_eq;
+
+#[test]
+fn webmcp_requirements_preserve_explicit_values_and_omission() {
+    for (contents, expected_browser_use, expected_empty) in [
+        ("", None, true),
+        ("[browser_use]", Some(None), true),
+        (
+            "[browser_use]\nallow_webmcp = true",
+            Some(Some(true)),
+            false,
+        ),
+        (
+            "[browser_use]\nallow_webmcp = false",
+            Some(Some(false)),
+            false,
+        ),
+    ] {
+        let requirements: ConfigRequirementsToml =
+            toml::from_str(contents).expect("parse managed WebMCP policy");
+        assert_eq!(
+            requirements,
+            ConfigRequirementsToml {
+                browser_use: expected_browser_use.map(|allow_webmcp| BrowserUseRequirementsToml {
+                    allow_webmcp,
+                    ..Default::default()
+                }),
+                ..Default::default()
+            },
+        );
+        assert_eq!(requirements.is_empty(), expected_empty, "{contents}");
+    }
+}
+
+#[test]
+fn webmcp_requirements_reject_non_booleans() {
+    for value in ["\"true\"", "1", "[]"] {
+        let contents = format!("[browser_use]\nallow_webmcp = {value}");
+        let error = toml::from_str::<ConfigRequirementsToml>(&contents)
+            .expect_err("WebMCP policy must be a boolean");
+        assert!(error.to_string().contains("allow_webmcp"));
+    }
+}

codex-rs/config/src/config_requirements.rs

@@ -2482,6 +2482,7 @@ mod tests {
         assert_eq!(
             requirements.browser_use,
             Some(BrowserUseRequirementsToml {
+                allow_webmcp: None,
                 allow_history_access: Some(false),
                 disable_auto_review: Some(true),
                 allow_global_persistent_approval: Some(false),
@@ -2714,6 +2715,7 @@ mod tests {
             entries: BTreeMap::from([("personality".to_string(), true)]),
         };
         let browser_use = BrowserUseRequirementsToml {
+            allow_webmcp: None,
             allow_history_access: Some(false),
             disable_auto_review: Some(true),
             allow_global_persistent_approval: None,

codex-rs/config/src/requirements_layers/stack_tests.rs

@@ -717,6 +717,33 @@ access = "deny"
     );
 }
 
+#[test]
+fn webmcp_requirements_preserve_managed_layer_precedence() {
+    for (lower, higher, expected) in [
+        ("true", "[browser_use]", true),
+        ("false", "[browser_use]", false),
+        ("true", "[browser_use]\nallow_webmcp = false", false),
+        ("false", "[browser_use]\nallow_webmcp = true", true),
+    ] {
+        let lower = format!("[browser_use]\nallow_webmcp = {lower}");
+        let composed = compose(vec![
+            layer("req_low", "Low", &lower),
+            layer("req_high", "High", higher),
+        ])
+        .expect("compose managed WebMCP policy");
+        assert_eq!(
+            composed,
+            Some(ConfigRequirementsToml {
+                browser_use: Some(crate::BrowserUseRequirementsToml {
+                    allow_webmcp: Some(expected),
+                    ..Default::default()
+                }),
+                ..Default::default()
+            }),
+        );
+    }
+}
+
 #[test]
 fn windows_requirements_use_regular_toml_merge() {
     let composed = compose(vec![