diff --git a/CHANGELOG.md b/CHANGELOG.md
index 086354ae499..3d0e2ba835f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -41,6 +41,7 @@ Docs: https://docs.openclaw.ai
 - WebChat/markdown tables: ensure GitHub-flavored markdown table parsing is explicitly enabled at render time and add horizontal overflow handling for wide tables, with regression coverage for table-only and mixed text+table content. (#32365) Thanks @BlueBirdBack.
 - Feishu/default account resolution: always honor explicit `channels.feishu.defaultAccount` during outbound account selection (including top-level-credential setups where the preferred id is not present in `accounts`), instead of silently falling back to another account id. (#32253) Thanks @bmendonca3.
 - Gemini schema sanitization: coerce malformed JSON Schema `properties` values (`null`, arrays, primitives) to `{}` before provider validation, preventing downstream strict-validator crashes on invalid plugin/tool schemas. (#32332) Thanks @webdevtodayjason.
+- Models/openai-completions developer-role compatibility: force `supportsDeveloperRole=false` for non-native endpoints, treat unparseable `baseUrl` values as non-native, and add regression coverage for empty/malformed baseUrl plus explicit-true override behavior. (#29479) thanks @akramcodez.
 - OpenAI/Responses WebSocket tool-call id hygiene: normalize blank/whitespace streamed tool-call ids before persistence, and block empty `function_call_output.call_id` payloads in the WS conversion path to avoid OpenAI 400 errors (`Invalid 'input[n].call_id': empty string`), with regression coverage for both inbound stream normalization and outbound payload guards.
 - Gateway/Control UI basePath webhook passthrough: let non-read methods under configured `controlUiBasePath` fall through to plugin routes (instead of returning Control UI 405), restoring webhook handlers behind basePath mounts. (#32311) Thanks @ademczuk.
 - CLI/Config validation and routing hardening: dedupe `openclaw config validate` failures to a single authoritative report, expose allowed-values metadata/hints across core Zod and plugin AJV validation (including `--json` fields), sanitize terminal-rendered validation text, and make command-path parsing root-option-aware across preaction/route/lazy registration (including routed `config get/unset` with split root options). Thanks @gumadeiras.
diff --git a/docs/concepts/model-providers.md b/docs/concepts/model-providers.md
index a2b777020d2..58710d88ee7 100644
--- a/docs/concepts/model-providers.md
+++ b/docs/concepts/model-providers.md
@@ -442,6 +442,9 @@ Notes:
   - `contextWindow: 200000`
   - `maxTokens: 8192`
 - Recommended: set explicit values that match your proxy/model limits.
+- For `api: "openai-completions"` on non-native endpoints (any non-empty `baseUrl` whose host is not `api.openai.com`), OpenClaw forces `compat.supportsDeveloperRole: false` to avoid provider 400 errors for unsupported `developer` roles.
+- If `baseUrl` is empty/omitted, OpenClaw keeps the default OpenAI behavior (which resolves to `api.openai.com`).
+- For safety, an explicit `compat.supportsDeveloperRole: true` is still overridden on non-native `openai-completions` endpoints.
 
 ## CLI examples
 
diff --git a/docs/gateway/configuration-reference.md b/docs/gateway/configuration-reference.md
index 37e64f2f840..b7486d50d9d 100644
--- a/docs/gateway/configuration-reference.md
+++ b/docs/gateway/configuration-reference.md
@@ -1961,6 +1961,7 @@ OpenClaw uses the pi-coding-agent model catalog. Add custom providers via `model
 - `models.providers.*.baseUrl`: upstream API base URL.
 - `models.providers.*.headers`: extra static headers for proxy/tenant routing.
 - `models.providers.*.models`: explicit provider model catalog entries.
+- `models.providers.*.models.*.compat.supportsDeveloperRole`: optional compatibility hint. For `api: "openai-completions"` with a non-empty non-native `baseUrl` (host not `api.openai.com`), OpenClaw forces this to `false` at runtime. Empty/omitted `baseUrl` keeps default OpenAI behavior.
 - `models.bedrockDiscovery`: Bedrock auto-discovery settings root.
 - `models.bedrockDiscovery.enabled`: turn discovery polling on/off.
 - `models.bedrockDiscovery.region`: AWS region for discovery.
diff --git a/src/agents/model-compat.test.ts b/src/agents/model-compat.test.ts
index 8bec5192a11..13a6cc002d9 100644
--- a/src/agents/model-compat.test.ts
+++ b/src/agents/model-compat.test.ts
@@ -19,6 +19,10 @@ const baseModel = (): Model<Api> =>
     maxTokens: 1024,
   }) as Model<Api>;
 
+function supportsDeveloperRole(model: Model<Api>): boolean | undefined {
+  return (model.compat as { supportsDeveloperRole?: boolean } | undefined)?.supportsDeveloperRole;
+}
+
 function createTemplateModel(provider: string, id: string): Model<Api> {
   return {
     id,
@@ -105,9 +109,7 @@ describe("normalizeModelCompat", () => {
     const model = baseModel();
     delete (model as { compat?: unknown }).compat;
     const normalized = normalizeModelCompat(model);
-    expect(
-      (normalized.compat as { supportsDeveloperRole?: boolean } | undefined)?.supportsDeveloperRole,
-    ).toBe(false);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
   });
 
   it("forces supportsDeveloperRole off for moonshot models", () => {
@@ -118,9 +120,7 @@ describe("normalizeModelCompat", () => {
     };
     delete (model as { compat?: unknown }).compat;
     const normalized = normalizeModelCompat(model);
-    expect(
-      (normalized.compat as { supportsDeveloperRole?: boolean } | undefined)?.supportsDeveloperRole,
-    ).toBe(false);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
   });
 
   it("forces supportsDeveloperRole off for custom moonshot-compatible endpoints", () => {
@@ -131,9 +131,7 @@ describe("normalizeModelCompat", () => {
     };
     delete (model as { compat?: unknown }).compat;
     const normalized = normalizeModelCompat(model);
-    expect(
-      (normalized.compat as { supportsDeveloperRole?: boolean } | undefined)?.supportsDeveloperRole,
-    ).toBe(false);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
   });
 
   it("forces supportsDeveloperRole off for DashScope provider ids", () => {
@@ -144,9 +142,7 @@ describe("normalizeModelCompat", () => {
     };
     delete (model as { compat?: unknown }).compat;
     const normalized = normalizeModelCompat(model);
-    expect(
-      (normalized.compat as { supportsDeveloperRole?: boolean } | undefined)?.supportsDeveloperRole,
-    ).toBe(false);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
   });
 
   it("forces supportsDeveloperRole off for DashScope-compatible endpoints", () => {
@@ -157,12 +153,10 @@ describe("normalizeModelCompat", () => {
     };
     delete (model as { compat?: unknown }).compat;
     const normalized = normalizeModelCompat(model);
-    expect(
-      (normalized.compat as { supportsDeveloperRole?: boolean } | undefined)?.supportsDeveloperRole,
-    ).toBe(false);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
   });
 
-  it("leaves non-zai models untouched", () => {
+  it("leaves native api.openai.com model untouched", () => {
     const model = {
       ...baseModel(),
       provider: "openai",
@@ -173,13 +167,89 @@ describe("normalizeModelCompat", () => {
     expect(normalized.compat).toBeUndefined();
   });
 
-  it("does not override explicit z.ai compat false", () => {
+  it("forces supportsDeveloperRole off for Azure OpenAI (Chat Completions, not Responses API)", () => {
+    const model = {
+      ...baseModel(),
+      provider: "azure-openai",
+      baseUrl: "https://my-deployment.openai.azure.com/openai",
+    };
+    delete (model as { compat?: unknown }).compat;
+    const normalized = normalizeModelCompat(model);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
+  });
+  it("forces supportsDeveloperRole off for generic custom openai-completions provider", () => {
+    const model = {
+      ...baseModel(),
+      provider: "custom-cpa",
+      baseUrl: "https://cpa.example.com/v1",
+    };
+    delete (model as { compat?: unknown }).compat;
+    const normalized = normalizeModelCompat(model);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
+  });
+
+  it("forces supportsDeveloperRole off for Qwen proxy via openai-completions", () => {
+    const model = {
+      ...baseModel(),
+      provider: "qwen-proxy",
+      baseUrl: "https://qwen-api.example.org/compatible-mode/v1",
+    };
+    delete (model as { compat?: unknown }).compat;
+    const normalized = normalizeModelCompat(model);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
+  });
+
+  it("leaves openai-completions model with empty baseUrl untouched", () => {
+    const model = {
+      ...baseModel(),
+      provider: "openai",
+    };
+    delete (model as { baseUrl?: unknown }).baseUrl;
+    delete (model as { compat?: unknown }).compat;
+    const normalized = normalizeModelCompat(model as Model<Api>);
+    expect(normalized.compat).toBeUndefined();
+  });
+
+  it("forces supportsDeveloperRole off for malformed baseUrl values", () => {
+    const model = {
+      ...baseModel(),
+      provider: "custom-cpa",
+      baseUrl: "://api.openai.com malformed",
+    };
+    delete (model as { compat?: unknown }).compat;
+    const normalized = normalizeModelCompat(model);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
+  });
+
+  it("overrides explicit supportsDeveloperRole true on non-native endpoints", () => {
+    const model = {
+      ...baseModel(),
+      provider: "custom-cpa",
+      baseUrl: "https://proxy.example.com/v1",
+      compat: { supportsDeveloperRole: true },
+    };
+    const normalized = normalizeModelCompat(model);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
+  });
+
+  it("does not mutate caller model when forcing supportsDeveloperRole off", () => {
+    const model = {
+      ...baseModel(),
+      provider: "custom-cpa",
+      baseUrl: "https://proxy.example.com/v1",
+    };
+    delete (model as { compat?: unknown }).compat;
+    const normalized = normalizeModelCompat(model);
+    expect(normalized).not.toBe(model);
+    expect(supportsDeveloperRole(model)).toBeUndefined();
+    expect(supportsDeveloperRole(normalized)).toBe(false);
+  });
+
+  it("does not override explicit compat false", () => {
     const model = baseModel();
     model.compat = { supportsDeveloperRole: false };
     const normalized = normalizeModelCompat(model);
-    expect(
-      (normalized.compat as { supportsDeveloperRole?: boolean } | undefined)?.supportsDeveloperRole,
-    ).toBe(false);
+    expect(supportsDeveloperRole(normalized)).toBe(false);
   });
 });
 
diff --git a/src/agents/model-compat.ts b/src/agents/model-compat.ts
index fc1c195819a..48990f10bfd 100644
--- a/src/agents/model-compat.ts
+++ b/src/agents/model-compat.ts
@@ -4,12 +4,20 @@ function isOpenAiCompletionsModel(model: Model<Api>): model is Model<"openai-com
   return model.api === "openai-completions";
 }
 
-function isDashScopeCompatibleEndpoint(baseUrl: string): boolean {
-  return (
-    baseUrl.includes("dashscope.aliyuncs.com") ||
-    baseUrl.includes("dashscope-intl.aliyuncs.com") ||
-    baseUrl.includes("dashscope-us.aliyuncs.com")
-  );
+/**
+ * Returns true only for endpoints that are confirmed to be native OpenAI
+ * infrastructure and therefore accept the `developer` message role.
+ * Azure OpenAI uses the Chat Completions API and does NOT accept `developer`.
+ * All other openai-completions backends (proxies, Qwen, GLM, DeepSeek, etc.)
+ * only support the standard `system` role.
+ */
+function isOpenAINativeEndpoint(baseUrl: string): boolean {
+  try {
+    const host = new URL(baseUrl).hostname.toLowerCase();
+    return host === "api.openai.com";
+  } catch {
+    return false;
+  }
 }
 
 function isAnthropicMessagesModel(model: Model<Api>): model is Model<"anthropic-messages"> {
@@ -40,24 +48,32 @@ export function normalizeModelCompat(model: Model<Api>): Model<Api> {
     }
   }
 
-  const isZai = model.provider === "zai" || baseUrl.includes("api.z.ai");
-  const isMoonshot =
-    model.provider === "moonshot" ||
-    baseUrl.includes("moonshot.ai") ||
-    baseUrl.includes("moonshot.cn");
-  const isDashScope = model.provider === "dashscope" || isDashScopeCompatibleEndpoint(baseUrl);
-  if ((!isZai && !isMoonshot && !isDashScope) || !isOpenAiCompletionsModel(model)) {
+  if (!isOpenAiCompletionsModel(model)) {
     return model;
   }
 
-  const openaiModel = model;
-  const compat = openaiModel.compat ?? undefined;
+  // The `developer` message role is an OpenAI-native convention. All other
+  // openai-completions backends (proxies, Qwen, GLM, DeepSeek, Kimi, etc.)
+  // only recognise `system`. Force supportsDeveloperRole=false for any model
+  // whose baseUrl is not a known native OpenAI endpoint, unless the caller
+  // has already pinned the value explicitly.
+  const compat = model.compat ?? undefined;
   if (compat?.supportsDeveloperRole === false) {
     return model;
   }
+  // When baseUrl is empty the pi-ai library defaults to api.openai.com, so
+  // leave compat unchanged and let the existing default behaviour apply.
+  // Note: an explicit supportsDeveloperRole: true is intentionally overridden
+  // here for non-native endpoints — those backends would return a 400 if we
+  // sent `developer`, so safety takes precedence over the caller's hint.
+  const needsForce = baseUrl ? !isOpenAINativeEndpoint(baseUrl) : false;
+  if (!needsForce) {
+    return model;
+  }
 
-  openaiModel.compat = compat
-    ? { ...compat, supportsDeveloperRole: false }
-    : { supportsDeveloperRole: false };
-  return openaiModel;
+  // Return a new object — do not mutate the caller's model reference.
+  return {
+    ...model,
+    compat: compat ? { ...compat, supportsDeveloperRole: false } : { supportsDeveloperRole: false },
+  } as typeof model;
 }