llm prompt -t filepath.yaml support, closes #897

docs/templates.md

@@ -64,6 +64,10 @@ Templates can also be specified as full URLs to YAML files:
 llm -t https://raw.githubusercontent.com/simonw/llm-templates/refs/heads/main/python-app.yaml \
   'Python app to pick a random line from a file'
 ```
+Or as a direct path to a YAML file on disk:
+```bash
+llm -t path/to/template.yaml 'extra prompt here'
+```
 
 (prompt-templates-list)=
 

llm/cli.py

@@ -3198,7 +3198,7 @@ def _parse_yaml_template(name, content):
 
 
 def load_template(name: str) -> Template:
-    "Or raises LoadTemplateError(msg)"
+    "Load template, or raise LoadTemplateError(msg)"
     if name.startswith("https://") or name.startswith("http://"):
         response = httpx.get(name)
         try:
@@ -3218,7 +3218,13 @@ def load_template(name: str) -> Template:
         except Exception as ex:
             raise LoadTemplateError("Could not load template {}: {}".format(name, ex))
 
-    path = template_dir() / f"{name}.yaml"
+    # First try local file
+    potential_path = pathlib.Path(name)
+    if potential_path.exists():
+        path = potential_path
+    else:
+        # Look for in template_dir()
+        path = template_dir() / f"{name}.yaml"
     if not path.exists():
         raise LoadTemplateError(f"Invalid template: {name}")
     content = path.read_text()

tests/test_templates.py

@@ -356,3 +356,17 @@ def test_execute_prompt_from_template_url(httpx_mock, template, expected):
     )
     assert result.exit_code == 0
     assert result.output.strip() == expected.strip()
+
+
+def test_execute_prompt_from_template_path():
+    runner = CliRunner()
+    with runner.isolated_filesystem() as temp_dir:
+        path = pathlib.Path(temp_dir) / "my-template.yaml"
+        path.write_text("system: system\nprompt: prompt", "utf-8")
+        result = runner.invoke(
+            cli,
+            ["-t", str(path), "-m", "echo"],
+            catch_exceptions=False,
+        )
+        assert result.exit_code == 0
+        assert result.output.strip() == "system:\nsystem\n\nprompt:\nprompt"