@@ -115,6 +115,15 @@ Command replies, review results, and terminal/retrying errors retain their exist
 failure channels. Clients advertising session compaction support continue to receive the dedicated
 compaction lifecycle instead of the legacy completion advisory.
 
+### Unsupported skills
+
+The adapter disables Codex skills whose output ACP clients cannot show, and leaves them out of the skill commands and
+`/skills`. The list is in `src/UnsupportedSkills.ts`. Today it holds Codex's bundled Visualize skill: it ends a reply
+with a content reference that only the OpenAI apps render, so ACP clients show raw `visualize{...}` text.
+
+The adapter matches skills by name, so it needs no `skills/list` request when a session starts. The cost: a skill from
+another plugin with the same qualified name, such as a `visualize` skill in some other plugin named `visualize`, is
+disabled too.
 
 ### App-server recovery
 
 
@@ -83,6 +83,7 @@ import {
     narrowToListedModels,
 } from "./GatewayModelDiscovery";
 import {findSupportedEffort} from "./ModelConfigOption";
+import {disableUnsupportedSkills, withoutUnsupportedSkills} from "./UnsupportedSkills";
 export type {SessionMetadata, SessionMetadataWithThread} from "./SessionMetadata";
 
 /**
@@ -1098,7 +1099,7 @@ export class CodexAcpClient {
             baseUrl: activeProvider.baseUrl,
         });
         const mergedConfig = {
-            ...forceGitRootTurnDiffPaths(mergeGatewayConfig(this.config, this.gatewayConfig)),
+            ...disableUnsupportedSkills(forceGitRootTurnDiffPaths(mergeGatewayConfig(this.config, this.gatewayConfig))),
             projects: Object.fromEntries(sessionRoots.map(root => [root, {
                 trust_level: "trusted",
             }])),
@@ -1335,7 +1336,7 @@ export class CodexAcpClient {
     }
 
     async listSkills(params?: SkillsListParams): Promise<SkillsListResponse> {
-        return this.codexClient.listSkills(params ?? {});
+        return withoutUnsupportedSkills(await this.codexClient.listSkills(params ?? {}));
     }
 
     private async awaitNextLoginCompleted(): Promise<AccountLoginCompletedNotification> {
 
@@ -0,0 +1,44 @@
+import type {JsonValue} from "./app-server/serde_json/JsonValue";
+import type {SkillsListResponse} from "./app-server/v2";
+
+/**
+ * Skills that ACP clients cannot use.
+ *
+ * Codex's bundled Visualize skill ends a reply with a content reference that only the OpenAI apps render,
+ * so ACP clients show it as raw `visualize{...}` text.
+ *
+ * Skills are matched by their plugin-qualified name, so that a session needs no `skills/list` lookup. A skill of
+ * another plugin with the same name, such as a `visualize` skill in some other `visualize` plugin, is disabled too.
+ */
+const UNSUPPORTED_SKILL_NAMES: ReadonlySet<string> = new Set(["visualize:visualize"]);
+
+type JsonObject = { [key in string]?: JsonValue };
+
+/** Adds the rules that disable the unsupported skills to a thread config. */
+export function disableUnsupportedSkills(config: JsonObject): JsonObject {
+    const skills = isJsonObject(config["skills"]) ? config["skills"] : {};
+    const rules = Array.isArray(skills["config"]) ? skills["config"] : [];
+    return {
+        ...config,
+        skills: {
+            ...skills,
+            // Last, because Codex lets a later rule for the same selector replace an earlier one.
+            config: [...rules, ...Array.from(UNSUPPORTED_SKILL_NAMES, name => ({name, enabled: false}))],
+        },
+    };
+}
+
+/** Removes the unsupported skills from a `skills/list` response. */
+export function withoutUnsupportedSkills(response: SkillsListResponse): SkillsListResponse {
+    return {
+        ...response,
+        data: response.data.map(entry => ({
+            ...entry,
+            skills: entry.skills.filter(skill => !UNSUPPORTED_SKILL_NAMES.has(skill.name)),
+        })),
+    };
+}
+
+function isJsonObject(value: JsonValue | undefined): value is JsonObject {
+    return value !== null && typeof value === "object" && !Array.isArray(value);
+}
@@ -1992,6 +1992,42 @@ describe('ACP server test', { timeout: 40_000 }, () => {
         expect(airSkill?._meta).toEqual({jetbrains: {air: {version: 1, skillPath: "/workspace/.agents/skills/build/SKILL.md"}}});
     });
 
+    it('does not offer the Visualize skill, whose output ACP clients cannot render', async () => {
+        const mockFixture = createCodexMockTestFixture();
+        const codexAcpAgent = mockFixture.getCodexAcpAgent();
+        const skill = (name: string, pluginId: string | null) => ({
+            name,
+            description: name,
+            path: `/workspace/.agents/skills/${name}/SKILL.md`,
+            scope: "user" as const,
+            enabled: true,
+            pluginId,
+        });
+        vi.spyOn(mockFixture.getCodexAppServerClient(), "listSkills").mockResolvedValue({
+            data: [{
+                cwd: "/workspace",
+                skills: [skill("visualize:visualize", "visualize@openai-bundled"), skill("build", null)],
+                errors: [],
+            }],
+        });
+        const sessionState = createTestSessionState({sessionId: "session-id", cwd: "/workspace"});
+        vi.spyOn(codexAcpAgent, "getSessionState").mockReturnValue(sessionState);
+
+        // @ts-expect-error - exercising private helper
+        await codexAcpAgent.availableCommands.publish(sessionState);
+        await codexAcpAgent.prompt({sessionId: "session-id", prompt: [{type: "text", text: "/skills"}]});
+
+        const events = mockFixture.getAcpConnectionEvents([])
+            .filter(event => event.method === "sessionUpdate")
+            .map(event => event.args[0].update);
+        const commands = events.find(update => update.sessionUpdate === "available_commands_update")
+            ?.availableCommands.map((command: acp.AvailableCommand) => command.name);
+        expect(commands).toContain("$build");
+        expect(commands).not.toContain("$visualize:visualize");
+        const skillsList = events.find(update => update.sessionUpdate === "agent_message_chunk")?.content.text;
+        expect(skillsList).toBe("Available skills:\n- build: build");
+    });
+
     it('publishes the commands again after a turn only when the skills changed', async () => {
         const mockFixture = createCodexMockTestFixture();
         const codexAcpAgent = mockFixture.getCodexAcpAgent();
 
@@ -19,6 +19,14 @@
           "features": {
             "cwd_relative_turn_diffs": false
           },
+          "skills": {
+            "config": [
+              {
+                "name": "visualize:visualize",
+                "enabled": false
+              }
+            ]
+          },
           "projects": {
             "/workspace": {
               "trust_level": "trusted"
 
@@ -167,6 +167,14 @@
           "features": {
             "cwd_relative_turn_diffs": false
           },
+          "skills": {
+            "config": [
+              {
+                "name": "visualize:visualize",
+                "enabled": false
+              }
+            ]
+          },
           "projects": {
             "/workspace": {
               "trust_level": "trusted"
 
@@ -6,6 +6,14 @@
         "features": {
           "cwd_relative_turn_diffs": false
         },
+        "skills": {
+          "config": [
+            {
+              "name": "visualize:visualize",
+              "enabled": false
+            }
+          ]
+        },
         "projects": {
           "/workspace": {
             "trust_level": "trusted"
 
@@ -166,6 +166,14 @@
           "features": {
             "cwd_relative_turn_diffs": false
           },
+          "skills": {
+            "config": [
+              {
+                "name": "visualize:visualize",
+                "enabled": false
+              }
+            ]
+          },
           "projects": {
             "/workspace": {
               "trust_level": "trusted"
 
@@ -166,6 +166,14 @@
           "features": {
             "cwd_relative_turn_diffs": false
           },
+          "skills": {
+            "config": [
+              {
+                "name": "visualize:visualize",
+                "enabled": false
+              }
+            ]
+          },
           "projects": {
             "/workspace": {
               "trust_level": "trusted"
 
@@ -166,6 +166,14 @@
           "features": {
             "cwd_relative_turn_diffs": false
           },
+          "skills": {
+            "config": [
+              {
+                "name": "visualize:visualize",
+                "enabled": false
+              }
+            ]
+          },
           "projects": {
             "/workspace": {
               "trust_level": "trusted"