diff --git a/.quixos-subtree-source.json b/.quixos-subtree-source.json
index dabb8cb..02680cb 100644
--- a/.quixos-subtree-source.json
+++ b/.quixos-subtree-source.json
@@ -1,7 +1,7 @@
 {
   "version": 1,
   "sourceRepo": "https://gitea.internal.quixos.org/quixos/quixos.git",
-  "sourceCommit": "ca5b05584b89e90cb259b4596b1bc01d3d692136",
+  "sourceCommit": "806b0430d952b5a9aab5b2a63496c272aced8e50",
   "sourcePath": "quixos-protocol",
   "exportName": "quixos-protocol",
   "mirrorRemote": "https://repos.quixos.org/quixos-toolchain/quixos-protocol.git"
diff --git a/src/capability-language/authoring-context.ts b/src/capability-language/authoring-context.ts
index 4a88a40..911b023 100644
--- a/src/capability-language/authoring-context.ts
+++ b/src/capability-language/authoring-context.ts
@@ -21,6 +21,8 @@ export async function authoringContext(start: string) {
     }
     if (text !== undefined) {
       const graph = JSON.parse(text) as { resources: AuthoringResource[]; workspaceId?: string };
+      if (!graph || typeof graph !== "object" || Array.isArray(graph))
+        throw new Error("Managed resource inventory is malformed");
       if (
         graph.workspaceId !== undefined &&
         (typeof graph.workspaceId !== "string" || !/^[a-zA-Z0-9][a-zA-Z0-9:._-]{0,255}$/.test(graph.workspaceId))
@@ -30,27 +32,68 @@ export async function authoringContext(start: string) {
       const resources: AuthoringResource[] = [{ kind: "workspace", directory: "root" }];
       const identities = new Set<string>(),
         directories = new Set<string>(["root"]);
-      for (const entry of graph.resources) {
-        // Compiler graphs carry resolved paths; the authoring API presents
-        // stable workbench-relative names and validates containment here.
-        if (typeof entry.directory === "string" && path.isAbsolute(entry.directory))
-          entry.directory = path.relative(workbench, entry.directory);
+      for (const [index, entry] of graph.resources.entries()) {
+        const invalid = (reason: string): never => {
+          throw new Error(`Invalid managed resource registration at entry ${index + 1}: ${reason}`);
+        };
         if (
-          !["interface", "package", "build"].includes(entry.kind) ||
-          !entry.source ||
-          !/^resources\/[A-Za-z0-9][A-Za-z0-9._-]*$/.test(entry.directory)
-        ) {
-          throw new Error("Invalid managed resource registration");
+          !entry ||
+          typeof entry !== "object" ||
+          Array.isArray(entry) ||
+          !["interface", "package", "build"].includes(entry.kind)
+        )
+          invalid("unsupported resource kind");
+        if (
+          entry.resourceId !== undefined &&
+          (typeof entry.resourceId !== "string" ||
+            entry.resourceId.length < 1 ||
+            entry.resourceId.length > 256 ||
+            entry.resourceId.includes("\0"))
+        )
+          invalid("resource identity must be a bounded nonempty identifier");
+        const source = entry.source;
+        if (
+          !source ||
+          typeof source !== "object" ||
+          Array.isArray(source) ||
+          source.resolver !== "git" ||
+          typeof source.repository !== "string" ||
+          !source.repository ||
+          source.repository.length > 4096 ||
+          source.repository.includes("\0") ||
+          typeof source.commit !== "string" ||
+          !/^([0-9a-f]{40}|[0-9a-f]{64})$/.test(source.commit)
+        )
+          invalid("expected an immutable Git source");
+        // Git transport policy belongs to the source resolver, including its
+        // maintained local/file fixtures; registration validates only its shape.
+        if (
+          typeof entry.directory !== "string" ||
+          !entry.directory ||
+          entry.directory.length > 4096 ||
+          entry.directory.includes("\0")
+        )
+          invalid("directory must be a bounded path");
+        // Bootstrap intentionally records stable aliases for native histories.
+        // Compare physical paths on BOTH sides, then expose the same canonical
+        // workbench-relative selection for alias and physical working dirs.
+        let directory: string;
+        try {
+          directory = path.relative(workbench, await realpath(path.resolve(workbench, entry.directory)));
+        } catch {
+          invalid("registered directory is unavailable");
         }
-        const identity = `${entry.kind}\0${entry.resourceId ?? entry.source.repository}`;
-        if (identities.has(identity) || directories.has(entry.directory)) {
-          throw new Error(`Multiple editable selections for ${entry.resourceId ?? entry.source.repository}`);
+        if (!/^resources\/[A-Za-z0-9][A-Za-z0-9._-]*$/.test(directory!))
+          invalid("registered directory must resolve beneath workbench resources");
+        const identity = `${entry.kind}\0${entry.resourceId ?? source!.repository}`;
+        if (identities.has(identity) || directories.has(directory!)) {
+          throw new Error(`Multiple editable selections for ${directory!}`);
         }
         identities.add(identity);
-        directories.add(entry.directory);
+        directories.add(directory!);
         resources.push({
           kind: entry.kind,
-          directory: entry.directory,
+          directory: directory!,
           resourceId: entry.resourceId,
           source: entry.source,
         });