MCP: headless open_file reads .pdf and PDF-compatible .ai, as File ▸ Open does

Headless `open_file` (and `file.open` through run_command) had its own
loader that stopped at .vectorcraft and .svg, so an agent could not open
a PDF or an .ai file without the desktop app, although the engine and
`vectorcraft-cli` already import them through vectorcraft-pdf.

The headless loader now imports .pdf, .ai and any file starting with
%PDF through vectorcraft_pdf::import_with_report (default options, as
File ▸ Open uses), and returns the import warnings like the SVG path.
The open_file tool description lists the new types.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

Cargo.lock

@@ -4185,6 +4185,7 @@ dependencies = [
  "vectorcraft-engine",
  "vectorcraft-format",
  "vectorcraft-geom",
+ "vectorcraft-pdf",
  "vectorcraft-render",
  "vectorcraft-svg",
  "vectorcraft-testkit",

crates/mcp/Cargo.toml

@@ -12,6 +12,7 @@ workspace = true
 vectorcraft-engine = { workspace = true }
 vectorcraft-render = { workspace = true }
 vectorcraft-svg = { workspace = true }
+vectorcraft-pdf = { workspace = true }
 vectorcraft-format = { workspace = true }
 vectorcraft-tools = { workspace = true }
 vectorcraft-geom = { workspace = true }

crates/mcp/src/headless.rs

@@ -215,7 +215,7 @@ impl Headless {
         }
     }
 
-    /// `app.open {path}`: `.vectorcraft` or `.svg` as a new active document.
+    /// `app.open {path}`: `.vectorcraft`, `.svg`, `.pdf` or PDF-compatible `.ai` as a new active document.
     pub fn open(&mut self, p: &Value) -> Result<Value, String> {
         let path = s(p, "path").ok_or("missing `path`")?;
         let bytes = std::fs::read(path).map_err(|e| format!("read {path}: {e}"))?;
@@ -234,8 +234,15 @@ impl Headless {
             d.title = name.clone();
             warnings = w;
             (d, false)
+        } else if e == "pdf" || e == "ai" || bytes.starts_with(b"%PDF") {
+            // PDF, or the PDF-compatible part of an Illustrator `.ai`, as in the app's File ▸ Open.
+            let r = vectorcraft_pdf::import_with_report(&bytes, &vectorcraft_pdf::ImportOptions::default()).map_err(|e| e.to_string())?;
+            let mut d = r.document;
+            d.title = name.clone();
+            warnings = r.warnings;
+            (d, false)
         } else {
-            return Err(format!("headless mode can open .vectorcraft and .svg files, not .{e}"));
+            return Err(format!("headless mode can open .vectorcraft, .svg, .pdf and .ai files, not .{e}"));
         };
         let index = self.session.add_document(doc, keep_path.then(|| path.to_string()));
         Ok(json!({"index": index, "title": name, "warnings": warnings}))

crates/mcp/src/tests.rs

@@ -200,6 +200,18 @@ fn headless_end_to_end() {
     let r = call(&mut s, 9, "open_file", json!({"path": svg_path.to_str().unwrap()}));
     assert_eq!(r["isError"], false, "{r}");
 
+    // PDF and PDF-compatible .ai open headless too.
+    let pdf_path = tmp("out.pdf");
+    assert_eq!(call(&mut s, 20, "export", json!({"path": pdf_path.to_str().unwrap()}))["isError"], false);
+    let ai_path = tmp("out.ai");
+    std::fs::copy(&pdf_path, &ai_path).unwrap();
+    for (id, p) in [(21, &pdf_path), (22, &ai_path)] {
+        let r = call(&mut s, id, "open_file", json!({"path": p.to_str().unwrap()}));
+        assert_eq!(r["isError"], false, "{r}");
+        let doc: Value = serde_json::from_str(&text_of(&call(&mut s, id + 10, "inspect_document", json!({})))).unwrap();
+        assert!(doc["objects"].as_u64().unwrap() >= 2, "{doc}");
+    }
+
     // Resources.
     let v = rpc(&mut s, 10, "resources/list", json!({}));
     assert_eq!(v["result"]["resources"].as_array().unwrap().len(), 2);

crates/mcp/src/tools.rs

@@ -246,7 +246,7 @@ pub fn tool_definitions() -> Vec<Value> {
         tool(
             "open_file",
             "Open file",
-            "Open a .vectorcraft or .svg file as a new, active document.",
+            "Open a .vectorcraft, .svg, .pdf or PDF-compatible .ai file as a new, active document.",
             obj(json!({"path": string("File path")}), &["path"]),
             false,
         ),