diff --git a/openkb/cli.py b/openkb/cli.py
index 028e546e..d91789f8 100644
--- a/openkb/cli.py
+++ b/openkb/cli.py
@@ -541,6 +541,17 @@ def lint(ctx, fix):
     from openkb.agent.linter import run_knowledge_lint
 
     openkb_dir = kb_dir / ".openkb"
+
+    # Skip lint entirely when the KB has no indexed documents
+    hashes_file = openkb_dir / "hashes.json"
+    if hashes_file.exists():
+        hashes = json.loads(hashes_file.read_text(encoding="utf-8"))
+    else:
+        hashes = {}
+    if not hashes:
+        click.echo("Nothing to lint — no documents indexed yet. Run `openkb add` first.")
+        return
+
     config = load_config(openkb_dir / "config.yaml")
     _setup_llm_key(kb_dir)
     model: str = config.get("model", DEFAULT_CONFIG["model"])
diff --git a/tests/test_lint_cli.py b/tests/test_lint_cli.py
new file mode 100644
index 00000000..bc207f08
--- /dev/null
+++ b/tests/test_lint_cli.py
@@ -0,0 +1,75 @@
+"""Tests for the openkb lint CLI command."""
+from __future__ import annotations
+
+import json
+from pathlib import Path
+from unittest.mock import patch
+
+from click.testing import CliRunner
+
+from openkb.cli import cli
+
+
+def _setup_kb(tmp_path: Path) -> Path:
+    """Create a minimal KB structure and return kb_dir."""
+    kb_dir = tmp_path
+    (kb_dir / "raw").mkdir()
+    (kb_dir / "wiki" / "sources" / "images").mkdir(parents=True)
+    (kb_dir / "wiki" / "summaries").mkdir(parents=True)
+    (kb_dir / "wiki" / "concepts").mkdir(parents=True)
+    (kb_dir / "wiki" / "reports").mkdir(parents=True)
+    openkb_dir = kb_dir / ".openkb"
+    openkb_dir.mkdir()
+    (openkb_dir / "config.yaml").write_text("model: gpt-4o-mini\n")
+    (openkb_dir / "hashes.json").write_text(json.dumps({}))
+    (kb_dir / "wiki" / "index.md").write_text(
+        "# Knowledge Base Index\n\n## Documents\n\n## Concepts\n"
+    )
+    return kb_dir
+
+
+class TestLintCommand:
+    def test_lint_empty_kb_skips(self, tmp_path):
+        """Lint on an empty KB (no indexed docs) should exit early."""
+        kb_dir = _setup_kb(tmp_path)
+        runner = CliRunner()
+        with patch("openkb.cli._find_kb_dir", return_value=kb_dir):
+            result = runner.invoke(cli, ["lint"])
+        assert result.exit_code == 0
+        assert "Nothing to lint" in result.output
+        assert "no documents indexed" in result.output
+        # No report should be written
+        reports = list((kb_dir / "wiki" / "reports").glob("*.md"))
+        assert reports == []
+
+    def test_lint_no_hashes_file_skips(self, tmp_path):
+        """Lint should also skip when hashes.json doesn't exist."""
+        kb_dir = _setup_kb(tmp_path)
+        (kb_dir / ".openkb" / "hashes.json").unlink()
+        runner = CliRunner()
+        with patch("openkb.cli._find_kb_dir", return_value=kb_dir):
+            result = runner.invoke(cli, ["lint"])
+        assert result.exit_code == 0
+        assert "Nothing to lint" in result.output
+
+    def test_lint_no_kb(self, tmp_path):
+        runner = CliRunner()
+        with runner.isolated_filesystem(temp_dir=tmp_path), \
+             patch("openkb.cli._find_kb_dir", return_value=None):
+            result = runner.invoke(cli, ["lint"])
+            assert "No knowledge base found" in result.output
+
+    def test_lint_runs_when_docs_exist(self, tmp_path):
+        """Lint should proceed when there are indexed documents."""
+        kb_dir = _setup_kb(tmp_path)
+        hashes = {"abc": {"name": "paper.pdf", "type": "pdf"}}
+        (kb_dir / ".openkb" / "hashes.json").write_text(json.dumps(hashes))
+        runner = CliRunner()
+        with patch("openkb.cli._find_kb_dir", return_value=kb_dir), \
+             patch("openkb.cli._setup_llm_key"), \
+             patch("openkb.agent.linter.run_knowledge_lint", return_value="No issues."):
+            result = runner.invoke(cli, ["lint"])
+        assert result.exit_code == 0
+        assert "Running structural lint" in result.output
+        assert "Running knowledge lint" in result.output
+        assert "Report written to" in result.output