feat: add memory tool (#10637)

Add a tool for memory to retrieve a full memory based on the memory ID

codex-rs/core/src/tools/spec.rs

@@ -31,6 +31,7 @@ pub(crate) struct ToolsConfig {
     pub web_search_mode: Option<WebSearchMode>,
     pub collab_tools: bool,
     pub collaboration_modes_tools: bool,
+    pub memory_tools: bool,
     pub request_rule_enabled: bool,
     pub experimental_supported_tools: Vec<String>,
 }
@@ -51,6 +52,7 @@ impl ToolsConfig {
         let include_apply_patch_tool = features.enabled(Feature::ApplyPatchFreeform);
         let include_collab_tools = features.enabled(Feature::Collab);
         let include_collaboration_modes_tools = features.enabled(Feature::CollaborationModes);
+        let include_memory_tools = features.enabled(Feature::MemoryTool);
         let request_rule_enabled = features.enabled(Feature::RequestRule);
 
         let shell_type = if !features.enabled(Feature::ShellTool) {
@@ -84,6 +86,7 @@ impl ToolsConfig {
             web_search_mode: *web_search_mode,
             collab_tools: include_collab_tools,
             collaboration_modes_tools: include_collaboration_modes_tools,
+            memory_tools: include_memory_tools,
             request_rule_enabled,
             experimental_supported_tools: model_info.experimental_supported_tools.clone(),
         }
@@ -634,6 +637,28 @@ fn create_request_user_input_tool() -> ToolSpec {
     })
 }
 
+fn create_get_memory_tool() -> ToolSpec {
+    let properties = BTreeMap::from([(
+        "memory_id".to_string(),
+        JsonSchema::String {
+            description: Some(
+                "Memory ID to fetch. Uses the thread ID as the memory identifier.".to_string(),
+            ),
+        },
+    )]);
+
+    ToolSpec::Function(ResponsesApiTool {
+        name: "get_memory".to_string(),
+        description: "Loads the full stored memory payload for a memory_id.".to_string(),
+        strict: false,
+        parameters: JsonSchema::Object {
+            properties,
+            required: Some(vec!["memory_id".to_string()]),
+            additional_properties: Some(false.into()),
+        },
+    })
+}
+
 fn create_close_agent_tool() -> ToolSpec {
     let mut properties = BTreeMap::new();
     properties.insert(
@@ -1228,6 +1253,7 @@ pub(crate) fn build_specs(
     use crate::tools::handlers::ApplyPatchHandler;
     use crate::tools::handlers::CollabHandler;
     use crate::tools::handlers::DynamicToolHandler;
+    use crate::tools::handlers::GetMemoryHandler;
     use crate::tools::handlers::GrepFilesHandler;
     use crate::tools::handlers::ListDirHandler;
     use crate::tools::handlers::McpHandler;
@@ -1249,6 +1275,7 @@ pub(crate) fn build_specs(
     let plan_handler = Arc::new(PlanHandler);
     let apply_patch_handler = Arc::new(ApplyPatchHandler);
     let dynamic_tool_handler = Arc::new(DynamicToolHandler);
+    let get_memory_handler = Arc::new(GetMemoryHandler);
     let view_image_handler = Arc::new(ViewImageHandler);
     let mcp_handler = Arc::new(McpHandler);
     let mcp_resource_handler = Arc::new(McpResourceHandler);
@@ -1308,6 +1335,11 @@ pub(crate) fn build_specs(
         builder.register_handler("request_user_input", request_user_input_handler);
     }
 
+    if config.memory_tools {
+        builder.push_spec(create_get_memory_tool());
+        builder.register_handler("get_memory", get_memory_handler);
+    }
+
     if let Some(apply_patch_tool_type) = &config.apply_patch_tool_type {
         match apply_patch_tool_type {
             ApplyPatchToolType::Freeform => {
@@ -1669,6 +1701,33 @@ mod tests {
         assert_contains_tool_names(&tools, &["request_user_input"]);
     }
 
+    #[test]
+    fn get_memory_requires_memory_tool_feature() {
+        let config = test_config();
+        let model_info = ModelsManager::construct_model_info_offline("gpt-5-codex", &config);
+        let mut features = Features::with_defaults();
+        features.disable(Feature::MemoryTool);
+        let tools_config = ToolsConfig::new(&ToolsConfigParams {
+            model_info: &model_info,
+            features: &features,
+            web_search_mode: Some(WebSearchMode::Cached),
+        });
+        let (tools, _) = build_specs(&tools_config, None, &[]).build();
+        assert!(
+            !tools.iter().any(|t| t.spec.name() == "get_memory"),
+            "get_memory should be disabled when memory_tool feature is off"
+        );
+
+        features.enable(Feature::MemoryTool);
+        let tools_config = ToolsConfig::new(&ToolsConfigParams {
+            model_info: &model_info,
+            features: &features,
+            web_search_mode: Some(WebSearchMode::Cached),
+        });
+        let (tools, _) = build_specs(&tools_config, None, &[]).build();
+        assert_contains_tool_names(&tools, &["get_memory"]);
+    }
+
     fn assert_model_tools(
         model_slug: &str,
         features: &Features,