diff --git a/packages/core/NEXT_CHANGELOG.md b/packages/core/NEXT_CHANGELOG.md
index 03e865d3..cc26e694 100644
--- a/packages/core/NEXT_CHANGELOG.md
+++ b/packages/core/NEXT_CHANGELOG.md
@@ -4,6 +4,8 @@
 
 ### New Features and Improvements
 
+- Added a `meta-harness` user-agent dimension that reports the omnigent meta-harness (detected via the `OMNIGENT` environment variable) independently of agent detection.
+
 ### Bug Fixes
 
 ### Documentation
diff --git a/packages/core/src/clientinfo/default.ts b/packages/core/src/clientinfo/default.ts
index d849d07d..e57800c1 100644
--- a/packages/core/src/clientinfo/default.ts
+++ b/packages/core/src/clientinfo/default.ts
@@ -1,6 +1,7 @@
 import {ClientInfo, sanitize} from './clientinfo';
 import {MODULE_NAME, VERSION, getBase} from './base';
 import {agentProvider} from './agent';
+import {metaHarnessProvider} from './meta-harness';
 
 interface EnvCheck {
   readonly name: string;
@@ -124,5 +125,12 @@ export function createDefault(): ClientInfo {
     pairs.push({key: 'agent', value: agent});
   }
 
+  // The meta-harness dimension is independent of agent detection: omnigent
+  // running Claude Code reports both agent/claude-code and meta-harness/omnigent.
+  const metaHarness = metaHarnessProvider();
+  if (metaHarness !== '') {
+    pairs.push({key: 'meta-harness', value: metaHarness});
+  }
+
   return ClientInfo.EMPTY.with(...pairs);
 }
diff --git a/packages/core/src/clientinfo/meta-harness.ts b/packages/core/src/clientinfo/meta-harness.ts
new file mode 100644
index 00000000..7c9c7334
--- /dev/null
+++ b/packages/core/src/clientinfo/meta-harness.ts
@@ -0,0 +1,63 @@
+/**
+ * Detects the agent meta-harness (e.g. omnigent) running the current process.
+ * A meta-harness orchestrates AI coding agents rather than being one, so it is
+ * reported as an independent `meta-harness/<name>` user-agent dimension
+ * alongside `agent/<name>`. Kept in sync across the Go, Java, Python, and
+ * TypeScript SDKs.
+ *
+ * @module
+ */
+
+interface KnownMetaHarness {
+  readonly envVar: string;
+  readonly product: string;
+}
+
+// Canonical list of known meta-harnesses, detected by env var presence. Keep
+// in sync with the Go, Java, and Python SDKs.
+const KNOWN_META_HARNESSES: readonly KnownMetaHarness[] = [
+  // OMNIGENT is set by the omnigent meta-harness
+  // (https://github.com/omnigent-ai/omnigent).
+  {envVar: 'OMNIGENT', product: 'omnigent'},
+];
+
+/**
+ * Checks environment variables for known meta-harnesses. Returns the product
+ * name when exactly one is set, `"multiple"` when more than one is set, or `""`
+ * when none is set. Detection is by presence, so any value (including empty)
+ * counts.
+ */
+export function lookupMetaHarnessProvider(): string {
+  const matches: string[] = [];
+  for (const h of KNOWN_META_HARNESSES) {
+    if (h.envVar in process.env) {
+      matches.push(h.product);
+    }
+  }
+  if (matches.length === 1) {
+    return matches[0];
+  }
+  if (matches.length > 1) {
+    return 'multiple';
+  }
+  return '';
+}
+
+let cached: string | undefined;
+
+/**
+ * Returns the detected meta-harness name, cached for the process lifetime.
+ */
+export function metaHarnessProvider(): string {
+  cached ??= lookupMetaHarnessProvider();
+  return cached;
+}
+
+/**
+ * Clears the cached meta-harness detection result so that the next call to
+ * {@link metaHarnessProvider} re-evaluates the environment. Exported for
+ * testing only.
+ */
+export function clearMetaHarnessCache(): void {
+  cached = undefined;
+}
diff --git a/packages/core/tests/clientinfo/default.test.ts b/packages/core/tests/clientinfo/default.test.ts
index 7e2d7cfc..5ac474b6 100644
--- a/packages/core/tests/clientinfo/default.test.ts
+++ b/packages/core/tests/clientinfo/default.test.ts
@@ -18,6 +18,7 @@ import {
   normalizeNodeVersion,
 } from '../../src/clientinfo/default';
 import {clearAgentCache} from '../../src/clientinfo/agent';
+import {clearMetaHarnessCache} from '../../src/clientinfo/meta-harness';
 
 describe('createDefault', () => {
   let savedEnv: NodeJS.ProcessEnv;
@@ -25,6 +26,7 @@ describe('createDefault', () => {
   beforeEach(() => {
     resetBase();
     clearAgentCache();
+    clearMetaHarnessCache();
     savedEnv = process.env;
     process.env = {...savedEnv};
   });
@@ -32,6 +34,7 @@ describe('createDefault', () => {
   afterEach(() => {
     process.env = savedEnv;
     clearAgentCache();
+    clearMetaHarnessCache();
   });
 
   const prefix = `${MODULE_NAME}/${VERSION} node/${CACHED_NODE_VERSION} os/${process.platform}`;
@@ -86,6 +89,16 @@ describe('createDefault', () => {
       env: {AGENT: 'somethingweird'},
       want: `${prefix} agent/somethingweird`,
     },
+    {
+      name: 'meta-harness only',
+      env: {OMNIGENT: '1'},
+      want: `${prefix} meta-harness/omnigent`,
+    },
+    {
+      name: 'agent and meta-harness reported independently',
+      env: {CLAUDECODE: '1', OMNIGENT: '1'},
+      want: `${prefix} agent/claude-code meta-harness/omnigent`,
+    },
     {
       name: 'databricks runtime',
       env: {DATABRICKS_RUNTIME_VERSION: '15.5'},
@@ -122,8 +135,9 @@ describe('createDefault', () => {
         GITHUB_ACTIONS: 'true',
         DATABRICKS_RUNTIME_VERSION: '15.5',
         CLAUDECODE: '1',
+        OMNIGENT: '1',
       },
-      want: `${prefix} upstream/terraform upstream-version/1.5.0 cicd/github runtime/15.5 agent/claude-code`,
+      want: `${prefix} upstream/terraform upstream-version/1.5.0 cicd/github runtime/15.5 agent/claude-code meta-harness/omnigent`,
     },
   ];
 
diff --git a/packages/core/tests/clientinfo/meta-harness.test.ts b/packages/core/tests/clientinfo/meta-harness.test.ts
new file mode 100644
index 00000000..f4d028d8
--- /dev/null
+++ b/packages/core/tests/clientinfo/meta-harness.test.ts
@@ -0,0 +1,78 @@
+import {describe, it, expect, beforeEach, afterEach} from 'vitest';
+import {
+  metaHarnessProvider,
+  clearMetaHarnessCache,
+  lookupMetaHarnessProvider,
+} from '../../src/clientinfo/meta-harness';
+
+describe('lookupMetaHarnessProvider', () => {
+  let savedEnv: NodeJS.ProcessEnv;
+
+  beforeEach(() => {
+    clearMetaHarnessCache();
+    savedEnv = process.env;
+    process.env = {};
+  });
+
+  afterEach(() => {
+    process.env = savedEnv;
+    clearMetaHarnessCache();
+  });
+
+  const testCases: {
+    name: string;
+    env: Record<string, string>;
+    want: string;
+  }[] = [
+    {
+      name: 'no meta-harness',
+      env: {},
+      want: '',
+    },
+    {
+      name: 'omnigent',
+      env: {OMNIGENT: '1'},
+      want: 'omnigent',
+    },
+    {
+      name: 'empty value still counts as set',
+      env: {OMNIGENT: ''},
+      want: 'omnigent',
+    },
+    {
+      name: 'an agent env var does not affect meta-harness detection',
+      env: {CLAUDECODE: '1'},
+      want: '',
+    },
+  ];
+
+  it.each(testCases)('$name', ({env, want}) => {
+    process.env = env;
+    expect(lookupMetaHarnessProvider()).toBe(want);
+  });
+});
+
+describe('metaHarnessProvider', () => {
+  let savedEnv: NodeJS.ProcessEnv;
+
+  beforeEach(() => {
+    clearMetaHarnessCache();
+    savedEnv = process.env;
+    process.env = {};
+  });
+
+  afterEach(() => {
+    process.env = savedEnv;
+    clearMetaHarnessCache();
+  });
+
+  it('caches the detection result for the process lifetime', () => {
+    process.env = {OMNIGENT: '1'};
+    expect(metaHarnessProvider()).toBe('omnigent');
+
+    // Changing the environment after the first call must not change the
+    // cached result.
+    process.env = {};
+    expect(metaHarnessProvider()).toBe('omnigent');
+  });
+});
diff --git a/packages/core/vitest.config.browser.ts b/packages/core/vitest.config.browser.ts
index 0a89d223..c227d5f4 100644
--- a/packages/core/vitest.config.browser.ts
+++ b/packages/core/vitest.config.browser.ts
@@ -13,6 +13,7 @@ export default defineConfig({
       'tests/profiles/resolve.test.ts',
       'tests/clientinfo/default.test.ts',
       'tests/clientinfo/agent.test.ts',
+      'tests/clientinfo/meta-harness.test.ts',
     ],
   },
 });