feat: add llms.txt endpoint for AI agents (#3877)

Co-authored-by: Storm Knight <storm-knight@openclaw.ai>
Co-authored-by: ThomsenDrake <drake@verqor.me>
Co-authored-by: Arc <33088785+arcbtc@users.noreply.github.com>
Co-authored-by: dni ⚡ <office@dnilabs.com>

lnbits/app.py

@@ -40,6 +40,7 @@ from lnbits.core.tasks import (
 )
 from lnbits.exceptions import register_exception_handlers
 from lnbits.helpers import version_parse
+from lnbits.llms_txt import create_llms_txt_route
 from lnbits.settings import settings
 from lnbits.tasks import (
     cancel_all_tasks,
@@ -102,6 +103,9 @@ async def startup(app: FastAPI):
     # register core routes
     init_core_routers(app)
 
+    # register llms.txt endpoint for AI agents
+    create_llms_txt_route(app)
+
     # initialize tasks
     register_async_tasks()
 

lnbits/llms_txt.py

@@ -0,0 +1,78 @@
+"""Generate llms.txt markdown from FastAPI OpenAPI schema for AI agents."""
+
+from typing import Any
+
+from fastapi import FastAPI
+from fastapi.responses import PlainTextResponse
+
+
+def generate_llms_txt(app: FastAPI) -> str:
+    """Convert an OpenAPI schema to llms.txt markdown format."""
+    openapi_schema = app.openapi()
+    lines: list[str] = []
+
+    # H1: API Title
+    info = openapi_schema.get("info", {})
+    title = info.get("title", "API")
+    lines.append(f"# {title}")
+    lines.append("")
+
+    # Blockquote: Description
+    description = info.get("description")
+    if description:
+        for line in description.strip().split("\n"):
+            lines.append(f"> {line}")
+        lines.append("")
+
+    # Group endpoints by tag
+    paths = openapi_schema.get("paths", {})
+    endpoints_by_tag: dict[str, list[dict[str, Any]]] = {}
+
+    for path, path_item in paths.items():
+        for method in ["get", "post", "put", "patch", "delete", "head", "options"]:
+            if method not in path_item:
+                continue
+            operation = path_item[method]
+            tags = operation.get("tags", ["Endpoints"])
+            tag = tags[0] if tags else "Endpoints"
+            if tag not in endpoints_by_tag:
+                endpoints_by_tag[tag] = []
+            endpoints_by_tag[tag].append(
+                {
+                    "path": path,
+                    "method": method.upper(),
+                    "operation": operation,
+                }
+            )
+
+    # Generate sections by tag
+    for tag, endpoints in endpoints_by_tag.items():
+        lines.append(f"## {tag}")
+        lines.append("")
+        for endpoint in endpoints:
+            method = endpoint["method"]
+            path = endpoint["path"]
+            operation = endpoint["operation"]
+            summary = operation.get("summary", "")
+            if summary:
+                lines.append(f"### `{method} {path}` - {summary}")
+            else:
+                lines.append(f"### `{method} {path}`")
+            lines.append("")
+        lines.append("")
+
+    return "\n".join(lines).strip() + "\n"
+
+
+def create_llms_txt_route(app: FastAPI) -> None:
+    """Add a /llms.txt endpoint to the app."""
+
+    @app.get(
+        "/llms.txt",
+        response_class=PlainTextResponse,
+        include_in_schema=False,
+        summary="Get LLM-friendly API documentation",
+    )
+    async def get_llms_txt() -> str:
+        """Return the API documentation in llms.txt markdown format."""
+        return generate_llms_txt(app)