Support @cursor context

Author: ericdallo

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Unreleased
 
 - Support timeout on `eca_shell_command` with default to 1min.
+- Support `@cursor` context representing the current editor cursor position. #103
 
 ## 0.50.2
 

docs/protocol.md

@@ -340,7 +340,7 @@ interface ChatPromptParams {
  */
 type ChatModel = string;
 
-type ChatContext = FileContext | DirectoryContext | WebContext | RepoMapContext | McpResourceContext;
+type ChatContext = FileContext | DirectoryContext | WebContext | RepoMapContext | CursorContext |McpResourceContext;
 
 /**
  * Context related to a file in the workspace
@@ -394,6 +394,33 @@ interface RepoMapContext {
     type: 'repoMap'; 
 }
 
+/**
+ * Context about the cursor position in editor, sent by client.
+ * Clients should track path and cursor position.
+ */
+interface CursorContext {
+    type: 'cursor'; 
+    
+    /**
+     * File path of where the cursor is.
+     */
+    path: string;
+    
+    /**
+     * Cursor position, if not using a selection start should be equal to end.
+     */
+    position: {
+       start: {
+           line: number;
+           character: number;
+       },
+       end: {
+           line: number;
+           character: number;
+       }
+    }
+}
+
 /***
  * A MCP resource available from a MCP server.
  */

src/eca/features/context.clj

@@ -36,7 +36,7 @@
 
 (defn raw-contexts->refined [contexts db config]
   (concat (agents-file-contexts db config)
-          (mapcat (fn [{:keys [type path lines-range uri]}]
+          (mapcat (fn [{:keys [type path lines-range position uri]}]
                     (case (name type)
                       "file" [{:type :file
                                :path path
@@ -50,6 +50,9 @@
                                                  :path filename
                                                  :content (llm-api/refine-file-context filename nil)}))))
                       "repoMap" [{:type :repoMap}]
+                      "cursor" [{:type :cursor
+                                 :path path
+                                 :position position}]
                       "mcpResource" (try
                                       (mapv
                                        (fn [{:keys [text]}]
@@ -59,7 +62,8 @@
                                        (:contents (f.mcp/get-resource! uri db)))
                                       (catch Exception e
                                         (logger/warn logger-tag (format "Error getting MCP resource %s: %s" uri (.getMessage e)))
-                                        []))))
+                                        []))
+                      nil))
                   contexts)))
 
 (defn ^:private contexts-for [root-filename query config]
@@ -114,7 +118,8 @@
                                              :path (shared/uri->filename uri)})
                         (:workspace-folders @db*))
         mcp-resources (mapv #(assoc % :type "mcpResource") (f.mcp/all-resources @db*))]
-    (concat [{:type "repoMap"}]
+    (concat [{:type "repoMap"}
+             {:type "cursor"}]
             root-dirs
             relative-files
             workspace-files

src/eca/features/prompt.clj

@@ -61,12 +61,16 @@
    ""
    "<contexts description=\"Manually provided by user, usually when provided user knows that your task is related to those files, so consider reliying on it but use tools to read/find any extra files/contexts if really needed.\">"
    (reduce
-    (fn [context-str {:keys [type path content partial uri]}]
+    (fn [context-str {:keys [type path position content partial uri]}]
       (str context-str (case type
                          :file (if partial
                                  (format "<file partial=true path=\"%s\">...\n%s\n...</file>\n" path content)
                                  (format "<file path=\"%s\">%s</file>\n" path content))
                          :repoMap (format "<repoMap description=\"Workspaces structure in a tree view, spaces represent file hierarchy\" >%s</repoMap>\n" @repo-map*)
+                         :cursor (format "<cursor description=\"Editor cursor position\" path=\"%s\" start=\"%s\" end=\"%s\"/>"
+                                         path
+                                         (str (:line (:start position)) ":" (:character (:start position)))
+                                         (str (:line (:end position)) ":" (:character (:end position))))
                          :mcpResource (format "<resource uri=\"%s\">%s</resource>\n" uri content)
                          "")))
     ""