feat: revision-2025-03-26 without streamable http (#84)

1. Suppot revision 2025-03-26 data types
2. Support meta, progress tokne, and extensions in request/notification,
3. Remove `Message`, use `JsonRpcMessage` directly

crates/rmcp/src/model/tool.rs

@@ -18,6 +18,102 @@ pub struct Tool {
     pub description: Option<Cow<'static, str>>,
     /// A JSON Schema object defining the expected parameters for the tool
     pub input_schema: Arc<JsonObject>,
+    /// Optional additional tool information.
+    pub annotations: Option<ToolAnnotations>,
+}
+
+/// Additional properties describing a Tool to clients.
+///
+/// NOTE: all properties in ToolAnnotations are **hints**.
+/// They are not guaranteed to provide a faithful description of
+/// tool behavior (including descriptive properties like `title`).
+///
+/// Clients should never make tool use decisions based on ToolAnnotations
+/// received from untrusted servers.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "camelCase")]
+pub struct ToolAnnotations {
+    /// A human-readable title for the tool.
+    pub title: Option<String>,
+
+    /// If true, the tool does not modify its environment.
+    ///
+    /// Default: false
+    pub read_only_hint: Option<bool>,
+
+    /// If true, the tool may perform destructive updates to its environment.
+    /// If false, the tool performs only additive updates.
+    ///
+    /// (This property is meaningful only when `readOnlyHint == false`)
+    ///
+    /// Default: true
+    /// A human-readable description of the tool's purpose.
+    pub destructive_hint: Option<bool>,
+
+    /// If true, calling the tool repeatedly with the same arguments
+    /// will have no additional effect on the its environment.
+    ///
+    /// (This property is meaningful only when `readOnlyHint == false`)
+    ///
+    /// Default: false.
+    pub idempotent_hint: Option<bool>,
+
+    /// If true, this tool may interact with an "open world" of external
+    /// entities. If false, the tool's domain of interaction is closed.
+    /// For example, the world of a web search tool is open, whereas that
+    /// of a memory tool is not.
+    ///
+    /// Default: true
+    pub open_world_hint: Option<bool>,
+}
+
+impl ToolAnnotations {
+    pub fn new() -> Self {
+        Self::default()
+    }
+    pub fn with_title<T>(title: T) -> Self
+    where
+        T: Into<String>,
+    {
+        ToolAnnotations {
+            title: Some(title.into()),
+            ..Self::default()
+        }
+    }
+    pub fn read_only(self, read_only: bool) -> Self {
+        ToolAnnotations {
+            read_only_hint: Some(read_only),
+            ..self
+        }
+    }
+    pub fn destructive(self, destructive: bool) -> Self {
+        ToolAnnotations {
+            destructive_hint: Some(destructive),
+            ..self
+        }
+    }
+    pub fn idempotent(self, idempotent: bool) -> Self {
+        ToolAnnotations {
+            idempotent_hint: Some(idempotent),
+            ..self
+        }
+    }
+    pub fn open_world(self, open_world: bool) -> Self {
+        ToolAnnotations {
+            open_world_hint: Some(open_world),
+            ..self
+        }
+    }
+
+    /// If not set, defaults to true.
+    pub fn is_destructive(&self) -> bool {
+        self.destructive_hint.unwrap_or(true)
+    }
+
+    /// If not set, defaults to false.
+    pub fn is_idempotent(&self) -> bool {
+        self.idempotent_hint.unwrap_or(false)
+    }
 }
 
 impl Tool {
@@ -32,6 +128,14 @@ impl Tool {
             name: name.into(),
             description: Some(description.into()),
             input_schema: input_schema.into(),
+            annotations: None,
+        }
+    }
+
+    pub fn annotate(self, annotations: ToolAnnotations) -> Self {
+        Tool {
+            annotations: Some(annotations),
+            ..self
         }
     }