commit 633e828a2e3850278dd1dfc838d70373d6c8e4ad
Author: fkrebs <fkrebs@nucli.de>
Date:   Thu May 21 07:30:51 2026 +0200

    chore: initial commit

diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..370af99
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,12 @@
+FROM ghcr.io/astral-sh/uv:python3.12-trixie-slim
+
+WORKDIR /app
+COPY server.py .
+
+RUN uv pip install --system fastmcp boto3
+
+ENV FASTMCP_HOST=0.0.0.0
+ENV FASTMCP_PORT=8000
+
+EXPOSE 8000
+CMD ["python", "server.py"]
diff --git a/server.py b/server.py
new file mode 100644
index 0000000..7e936ae
--- /dev/null
+++ b/server.py
@@ -0,0 +1,125 @@
+"""
+upload-artifact MCP server — upload files/text/images to the chat-artifacts S3 bucket.
+
+The chat-artifacts bucket on Garage S3 is public-read (website endpoint).
+Objects are accessible at: https://chat-artifacts.s3.nuclide.systems/<key>
+
+Tools:
+  upload_text      — upload a text string (Markdown, HTML, SVG, CSV, …)
+  upload_base64    — upload binary content supplied as base64
+  list_artifacts   — list recent artifacts (optionally filtered by prefix)
+  get_url          — get the public URL for an artifact key
+  delete_artifact  — delete an artifact by key
+"""
+from __future__ import annotations
+
+import base64
+import mimetypes
+import os
+from datetime import datetime, timezone
+
+import boto3
+from botocore.config import Config
+from fastmcp import FastMCP
+
+ENDPOINT    = os.environ.get("CHAT_ARTIFACTS_ENDPOINT", "https://s3.nuclide.systems")
+ACCESS_KEY  = os.environ.get("CHAT_ARTIFACTS_ACCESS_KEY", "")
+SECRET_KEY  = os.environ.get("CHAT_ARTIFACTS_SECRET_KEY", "")
+BUCKET      = os.environ.get("CHAT_ARTIFACTS_BUCKET", "chat-artifacts")
+PUBLIC_BASE = "https://chat-artifacts.s3.nuclide.systems"
+
+mcp = FastMCP("upload-artifact")
+
+
+def _s3():
+    return boto3.client(
+        "s3",
+        endpoint_url=ENDPOINT,
+        aws_access_key_id=ACCESS_KEY,
+        aws_secret_access_key=SECRET_KEY,
+        region_name="garage",
+        config=Config(signature_version="s3v4"),
+    )
+
+
+def _date_prefix() -> str:
+    return datetime.now(timezone.utc).strftime("%Y-%m-%d/")
+
+
+@mcp.tool()
+def upload_text(
+    content: str,
+    filename: str,
+    content_type: str = "text/plain; charset=utf-8",
+    prefix: str = "",
+) -> dict:
+    """Upload a text string to the chat-artifacts bucket and return a public URL.
+
+    content_type examples: 'text/markdown', 'text/html', 'image/svg+xml', 'text/csv'.
+    prefix: optional subfolder (e.g. 'plots/', 'reports/'). Auto-date-prefixed if empty.
+    """
+    key = f"{prefix or _date_prefix()}{filename}"
+    body = content.encode("utf-8")
+    _s3().put_object(Bucket=BUCKET, Key=key, Body=body, ContentType=content_type)
+    return {"key": key, "url": f"{PUBLIC_BASE}/{key}", "bytes": len(body)}
+
+
+@mcp.tool()
+def upload_base64(
+    data_b64: str,
+    filename: str,
+    content_type: str = "application/octet-stream",
+    prefix: str = "",
+) -> dict:
+    """Upload binary content (base64-encoded) to the chat-artifacts bucket.
+
+    Useful for PNG/JPEG images, PDFs, ZIP archives.
+    data_b64: standard or URL-safe base64; padding is optional.
+    Returns the public URL.
+    """
+    data = base64.b64decode(data_b64 + "==")
+    key = f"{prefix or _date_prefix()}{filename}"
+    if content_type == "application/octet-stream":
+        guessed, _ = mimetypes.guess_type(filename)
+        if guessed:
+            content_type = guessed
+    _s3().put_object(Bucket=BUCKET, Key=key, Body=data, ContentType=content_type)
+    return {"key": key, "url": f"{PUBLIC_BASE}/{key}", "bytes": len(data)}
+
+
+@mcp.tool()
+def list_artifacts(prefix: str = "", limit: int = 20) -> list[dict]:
+    """List artifacts in the chat-artifacts bucket, newest first.
+
+    prefix: filter by key prefix (e.g. '2026-05-21/' or 'plots/').
+    Returns list of {key, bytes, last_modified, url}.
+    """
+    resp = _s3().list_objects_v2(Bucket=BUCKET, Prefix=prefix, MaxKeys=limit)
+    objs = sorted(resp.get("Contents", []), key=lambda o: o["LastModified"], reverse=True)
+    return [
+        {
+            "key": o["Key"],
+            "bytes": o["Size"],
+            "last_modified": o["LastModified"].isoformat(),
+            "url": f"{PUBLIC_BASE}/{o['Key']}",
+        }
+        for o in objs
+    ]
+
+
+@mcp.tool()
+def get_url(key: str) -> str:
+    """Return the public URL for a known artifact key."""
+    return f"{PUBLIC_BASE}/{key}"
+
+
+@mcp.tool()
+def delete_artifact(key: str) -> str:
+    """Delete an artifact by key. This is irreversible — confirm with the user first."""
+    _s3().delete_object(Bucket=BUCKET, Key=key)
+    return f"Deleted: {key}"
+
+
+if __name__ == "__main__":
+    import asyncio
+    asyncio.run(mcp.run_http_async(host="0.0.0.0", port=8000))