fix: use proper type guards instead of manual property checks

Address review feedback by using isEntityContext() type guard instead of
checking 'isPR' in context manually. This provides better type safety
and uses the existing type guard infrastructure.

src/mcp/install-mcp-server.ts

@@ -1,6 +1,7 @@
 import * as core from "@actions/core";
 import { GITHUB_API_URL, GITHUB_SERVER_URL } from "../github/api/config";
-import type { ParsedGitHubContext } from "../github/context";
+import type { GitHubContext } from "../github/context";
+import { isEntityContext } from "../github/context";
 import { Octokit } from "@octokit/rest";
 
 type PrepareConfigParams = {
@@ -12,7 +13,7 @@ type PrepareConfigParams = {
   additionalMcpConfig?: string;
   claudeCommentId?: string;
   allowedTools: string[];
-  context: ParsedGitHubContext;
+  context: GitHubContext;
 };
 
 async function checkActionsReadPermission(
@@ -115,7 +116,7 @@ export async function prepareMcpConfig(
     const hasActionsReadPermission =
       context.inputs.additionalPermissions.get("actions") === "read";
 
-    if (context.isPR && hasActionsReadPermission) {
+    if (isEntityContext(context) && context.isPR && hasActionsReadPermission) {
       // Verify the token actually has actions:read permission
       const actuallyHasPermission = await checkActionsReadPermission(
         process.env.ACTIONS_TOKEN || "",
@@ -141,7 +142,9 @@ export async function prepareMcpConfig(
           GITHUB_TOKEN: process.env.ACTIONS_TOKEN,
           REPO_OWNER: owner,
           REPO_NAME: repo,
-          PR_NUMBER: context.entityNumber?.toString() || "",
+          PR_NUMBER: isEntityContext(context)
+            ? context.entityNumber?.toString() || ""
+            : "",
           RUNNER_TEMP: process.env.RUNNER_TEMP || "/tmp",
         },
       };

src/modes/agent/index.ts

@@ -2,6 +2,7 @@ import * as core from "@actions/core";
 import type { Mode, ModeOptions, ModeResult } from "../types";
 import { isAutomationContext } from "../../github/context";
 import type { PreparedContext } from "../../create-prompt/types";
+import { prepareMcpConfig } from "../../mcp/install-mcp-server";
 
 /**
  * Agent mode implementation.
@@ -39,7 +40,7 @@ export const agentMode: Mode = {
     return false;
   },
 
-  async prepare({ context }: ModeOptions): Promise<ModeResult> {
+  async prepare({ context, githubToken }: ModeOptions): Promise<ModeResult> {
     // Agent mode handles automation events (workflow_dispatch, schedule) only
 
     // Agent mode doesn't need to create prompt files here - handled by createPrompt
@@ -67,26 +68,21 @@ export const agentMode: Mode = {
     core.exportVariable("INPUT_ALLOWED_TOOLS", allowedTools.join(","));
     core.exportVariable("INPUT_DISALLOWED_TOOLS", disallowedTools.join(","));
 
-    // Agent mode uses a minimal MCP configuration
-    // We don't need comment servers or PR-specific tools for automation
-    const mcpConfig: any = {
-      mcpServers: {},
-    };
-
-    // Add user-provided additional MCP config if any
+    // Get MCP configuration using the same setup as other modes
     const additionalMcpConfig = process.env.MCP_CONFIG || "";
-    if (additionalMcpConfig.trim()) {
-      try {
-        const additional = JSON.parse(additionalMcpConfig);
-        if (additional && typeof additional === "object") {
-          Object.assign(mcpConfig, additional);
-        }
-      } catch (error) {
-        core.warning(`Failed to parse additional MCP config: ${error}`);
-      }
-    }
+    const mcpConfig = await prepareMcpConfig({
+      githubToken,
+      owner: context.repository.owner,
+      repo: context.repository.repo,
+      branch: "", // Agent mode doesn't use branches
+      baseBranch: "",
+      additionalMcpConfig,
+      claudeCommentId: undefined, // Agent mode doesn't track comments
+      allowedTools: [...baseTools, ...context.inputs.allowedTools],
+      context,
+    });
 
-    core.setOutput("mcp_config", JSON.stringify(mcpConfig));
+    core.setOutput("mcp_config", mcpConfig);
 
     return {
       commentId: undefined,
@@ -95,7 +91,7 @@ export const agentMode: Mode = {
         currentBranch: "",
         claudeBranch: undefined,
       },
-      mcpConfig: JSON.stringify(mcpConfig),
+      mcpConfig: mcpConfig,
     };
   },