Revert "fix: graceful WebFetch fallback when MCP tools unavailable (#230)"

This reverts commit b4edff1898.

hooks/core/routing.mjs

@@ -273,21 +273,9 @@ export function routePreToolUse(toolName, toolInput, projectDir, platform) {
     return guidanceOnce("grep", grepGuidance);
   }
 
-  // ─── WebFetch: deny + redirect to sandbox (with graceful fallback #230) ───
+  // ─── WebFetch: deny + redirect to sandbox ───
   if (canonical === "WebFetch") {
     const url = toolInput.url ?? "";
-    // Deny once per session — if agent retries, MCP tools are likely unavailable.
-    // Graceful degradation: allow WebFetch as fallback rather than leaving agent stuck.
-    const marker = resolve(_guidanceDir, "webfetch-deny");
-    try {
-      mkdirSync(_guidanceDir, { recursive: true });
-      const fd = openSync(marker, fsConstants.O_CREAT | fsConstants.O_EXCL | fsConstants.O_WRONLY);
-      closeSync(fd);
-    } catch {
-      // Already denied once this session — MCP server may not be available (#230).
-      // Allow WebFetch as fallback to prevent agent from getting stuck.
-      return null;
-    }
     return {
       action: "deny",
       reason: `context-mode: WebFetch blocked. Think in Code — use ${t("ctx_fetch_and_index")}(url: "${url}", source: "...") to fetch and index, then ${t("ctx_search")}(queries: [...]) to query. Or use ${t("ctx_execute")}(language, code) to fetch, process, and console.log() only what you need. Write pure JS, no npm deps. Do NOT use curl, wget, or WebFetch.`,

tests/hooks/core-routing.test.ts

@@ -283,17 +283,6 @@ describe("routePreToolUse", () => {
       expect(result!.reason).toContain("fetch_and_index");
       expect(result!.reason).toContain("ctx_search");
     });
-
-    it("allows WebFetch on retry when MCP tools unavailable (#230)", () => {
-      // First call: deny + redirect to ctx_fetch_and_index
-      const first = routePreToolUse("WebFetch", { url: "https://example.com" });
-      expect(first).not.toBeNull();
-      expect(first!.action).toBe("deny");
-
-      // Second call: agent retries because MCP tools unavailable — allow fallback
-      const second = routePreToolUse("WebFetch", { url: "https://example.com" });
-      expect(second).toBeNull(); // passthrough
-    });
   });
 
   // ─── Task routing ──────────────────────────────────────