update to new nightly rust toolchain

README.md

@@ -194,13 +194,13 @@ cargo install rust-docs-mcp
 - Rust nightly toolchain (for Rustdoc JSON generation)
 
   ```bash
-  rustup toolchain install nightly
+  rustup toolchain install nightly-2026-05-22
   ```
 
-  Runtime prefers `nightly-2025-06-24` because it matches the rustdoc JSON
-  schema used by `rustdoc-types`, but it will fall back to `nightly` when that
-  toolchain produces the same JSON format version. You can override the choice
-  with:
+  Runtime prefers `nightly-2026-05-22`, which provides rustc
+  `1.97.0-nightly (e96c36b6f 2026-05-21)`, so documentation generation can
+  compile modern crates. The `rustdoc-types` dependency is kept in sync with
+  that rustdoc JSON format. You can override the choice with:
 
   ```bash
   export RUST_DOCS_MCP_TOOLCHAIN=nightly

rust-docs-mcp/Cargo.toml

@@ -28,7 +28,7 @@ flate2 = "1.0"
 futures = "0.3"
 git2 = "0.20"
 reqwest = { version = "0.12", features = ["json", "stream"] }
-rustdoc-types = { version = "0.53.0", features = ["rustc-hash"] }
+rustdoc-types = { version = "0.57.3", features = ["rustc-hash"] }
 semver = "1.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"

rust-docs-mcp/src/docs/query.rs

@@ -88,10 +88,9 @@ pub fn build_item_info(crate_data: &Crate, id: &Id, item: &Item) -> Option<ItemI
     // crate's `paths` map for items (e.g. impl blocks) that don't store one.
     let name = if let Some(name) = &item.name {
         name.clone()
-    } else if let Some(path_summary) = crate_data.paths.get(id) {
-        path_summary.path.last()?.clone()
     } else {
-        return None;
+        let path_summary = crate_data.paths.get(id)?;
+        path_summary.path.last()?.clone()
     };
 
     Some(ItemInfo {

rust-docs-mcp/src/rustdoc.rs

@@ -12,8 +12,9 @@ use std::sync::OnceLock;
 use std::time::Duration;
 use tokio::process::Command as TokioCommand;
 
-/// Preferred nightly toolchain version known to match `rustdoc-types`.
-pub const PREFERRED_TOOLCHAIN: &str = "nightly-2025-06-24";
+/// Preferred nightly toolchain. Keep this new enough to compile modern crates
+/// and keep `rustdoc-types` in sync with its rustdoc JSON format.
+pub const PREFERRED_TOOLCHAIN: &str = "nightly-2026-05-22";
 
 /// Fallback nightly alias to try when the preferred dated toolchain is unavailable.
 pub const FALLBACK_TOOLCHAIN: &str = "nightly";
@@ -156,7 +157,7 @@ fn is_missing_toolchain_error(stderr: &str, toolchain: &str) -> bool {
     // Extract toolchain name from rustup's error format: 'toolchain-name'
     // Then check it matches our query, allowing for an architecture suffix
     // (e.g., "nightly" -> "nightly-aarch64-apple-darwin") but not a date suffix
-    // (e.g., "nightly" should NOT match "nightly-2025-06-24-aarch64-apple-darwin")
+    // (e.g., "nightly" should NOT match "nightly-2026-05-22-aarch64-apple-darwin")
     stderr.split('\'').nth(1).is_some_and(|name| {
         name == toolchain
             || name

rust-toolchain.toml

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2025-06-24"
+channel = "nightly-2026-05-22"
 components = ["rustfmt", "clippy", "rust-src", "rust-docs-json"]