Remove canvas tools field

jmoseley · Copilot · jmoseley · commit c50b72876d84 · 2026-05-24T00:23:48.000-07:00
Drop CanvasToolDefinition, CanvasToolDefinitionDefer, and the
CanvasOpenResponse.tools / OpenCanvasInstance.tools fields from both
the Node and Rust SDKs. The CLI side is being removed in lockstep, so
the wire contract no longer carries this field.

Co-authored-by: Copilot &lt;223556219+Copilot@users.noreply.github.com&gt;
diff --git a/nodejs/src/canvas.ts b/nodejs/src/canvas.ts
@@ -13,20 +13,9 @@
  * focuses an existing panel; reload is a renderer-only concern.
  */
 
-/** JSON Schema object used for canvas inputs and canvas-scoped tools. */
+/** JSON Schema object used for canvas inputs. */
 export type CanvasJsonSchema = Record<string, unknown>;
 
-/** Tool definition exposed to a canvas instance. */
-export interface CanvasToolDefinition {
-    name: string;
-    description: string;
-    title?: string;
-    parameters?: CanvasJsonSchema;
-    overridesBuiltInTool?: boolean;
-    skipPermission?: boolean;
-    defer?: "auto" | "never";
-}
-
 /**
  * A single agent-callable action contributed by a canvas. The metadata
  * (`name`, `description`, `inputSchema`) is serialized over the wire on
@@ -72,8 +61,6 @@ export interface CanvasOpenResponse {
     title?: string;
     /** Provider-supplied status text shown in host chrome. */
     status?: string;
-    /** Tools available to the canvas instance. */
-    tools?: CanvasToolDefinition[];
 }
 
 /** Host capabilities passed to canvas callbacks. */
diff --git a/nodejs/src/extension.ts b/nodejs/src/extension.ts
@@ -24,7 +24,6 @@ export {
     type CanvasOpenContext,
     type CanvasOpenResponse,
     type CanvasOptions,
-    type CanvasToolDefinition,
 } from "./canvas.js";
 
 export type JoinSessionConfig = Omit<ResumeSessionConfig, "onPermissionRequest"> & {
diff --git a/nodejs/src/index.ts b/nodejs/src/index.ts
@@ -24,7 +24,6 @@ export {
     type CanvasOpenContext,
     type CanvasOpenResponse,
     type CanvasOptions,
-    type CanvasToolDefinition,
 } from "./canvas.js";
 export {
     defineTool,
diff --git a/rust/src/canvas.rs b/rust/src/canvas.rs
@@ -13,41 +13,6 @@ use crate::types::SessionId;
 /// JSON Schema object used for canvas inputs and canvas-scoped tools.
 pub type CanvasJsonSchema = serde_json::Map<String, Value>;
 
-/// Tool definition exposed to a canvas instance.
-#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
-#[serde(rename_all = "camelCase")]
-pub struct CanvasToolDefinition {
-    /// Tool name.
-    pub name: String,
-    /// Tool description.
-    pub description: String,
-    /// Human-readable tool title.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub title: Option<String>,
-    /// JSON Schema parameters for the tool.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub parameters: Option<Value>,
-    /// Whether this tool overrides a built-in tool.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub overrides_built_in_tool: Option<bool>,
-    /// Whether this tool skips permission prompts.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub skip_permission: Option<bool>,
-    /// Tool deferral behavior.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub defer: Option<CanvasToolDefinitionDefer>,
-}
-
-/// Tool deferral behavior for canvas-scoped tools.
-#[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq)]
-#[serde(rename_all = "kebab-case")]
-pub enum CanvasToolDefinitionDefer {
-    /// The tool may be deferred by the runtime.
-    Auto,
-    /// The tool is always included in the initial tool list.
-    Never,
-}
-
 /// Runtime-controlled routing state for an open canvas instance.
 #[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq)]
 #[serde(rename_all = "lowercase")]
@@ -130,9 +95,6 @@ pub struct CanvasOpenResponse {
     /// Provider-supplied status text shown in host chrome.
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub status: Option<String>,
-    /// Tools available to the canvas instance.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub tools: Option<Vec<CanvasToolDefinition>>,
 }
 
 /// Open canvas instance returned by `session.canvas.open`,
@@ -159,9 +121,6 @@ pub struct OpenCanvasInstance {
     /// URL for web-rendered canvases.
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub url: Option<String>,
-    /// Tools available to the canvas instance.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub tools: Option<Vec<CanvasToolDefinition>>,
     /// Input supplied when the instance was opened.
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub input: Option<Value>,
@@ -186,7 +145,6 @@ impl OpenCanvasInstance {
             title: None,
             status: None,
             url: None,
-            tools: None,
             input: None,
             reopen: false,
             availability: CanvasInstanceAvailability::Stale,
@@ -652,7 +610,6 @@ mod tests {
                 url: Some(format!("https://example.test/{}", ctx.canvas_id)),
                 title: Some("Echo".to_string()),
                 status: Some("ready".to_string()),
-                tools: None,
             })
         }
 
diff --git a/rust/tests/session_test.rs b/rust/tests/session_test.rs
@@ -36,7 +36,6 @@ impl CanvasHandler for TestCanvasHandler {
             url: Some(format!("https://example.test/{}", ctx.canvas_id)),
             title: Some("Test Canvas".to_string()),
             status: Some("ready".to_string()),
-            tools: None,
         })
     }
 

Original file line number	Diff line number	Diff line change
`@@ -36,7 +36,6 @@ impl CanvasHandler for TestCanvasHandler {`
`36`	`36`	`url: Some(format!("https://example.test/{}", ctx.canvas_id)),`
`37`	`37`	`title: Some("Test Canvas".to_string()),`
`38`	`38`	`status: Some("ready".to_string()),`
`39`		`- tools: None,`
`40`	`39`	`})`
`41`	`40`	`}`
`42`	`41`