improve mcp context initialization

mcp/selectMode.ts

@@ -1,20 +1,6 @@
 import { type } from "arktype";
-import type { Mode } from "../modes.ts";
 import { contextualize, tool } from "./shared.ts";
 
-// Get modes from environment variable (set by createMcpConfigs)
-function getModes(): Mode[] {
-  const modesJson = process.env.PULLFROG_MODES;
-  if (modesJson) {
-    try {
-      return JSON.parse(modesJson);
-    } catch {
-      return [];
-    }
-  }
-  return [];
-}
-
 export const SelectMode = type({
   modeName: type.string.describe(
     "the name of the mode to select (e.g., 'Plan', 'Build', 'Review', 'Prompt')"
@@ -26,23 +12,14 @@ export const SelectModeTool = tool({
   description:
     "Select a mode and get its detailed prompt instructions. Call this first to determine which mode to use based on the request.",
   parameters: SelectMode,
-  execute: contextualize(async ({ modeName }) => {
-    const allModes = getModes();
-
-    if (allModes.length === 0) {
-      return {
-        error:
-          "No modes available. Modes must be provided via PULLFROG_MODES environment variable.",
-      };
-    }
-
-    const selectedMode = allModes.find((m) => m.name.toLowerCase() === modeName.toLowerCase());
+  execute: contextualize(async ({ modeName }, ctx) => {
+    const selectedMode = ctx.modes.find((m) => m.name.toLowerCase() === modeName.toLowerCase());
 
     if (!selectedMode) {
-      const availableModes = allModes.map((m) => m.name).join(", ");
+      const availableModes = ctx.modes.map((m) => m.name).join(", ");
       return {
         error: `Mode "${modeName}" not found. Available modes: ${availableModes}`,
-        availableModes: allModes.map((m) => ({ name: m.name, description: m.description })),
+        availableModes: ctx.modes.map((m) => ({ name: m.name, description: m.description })),
       };
     }
 

mcp/server.ts

@@ -20,7 +20,7 @@ import { PullRequestInfoTool } from "./prInfo.ts";
 import { ReviewTool } from "./review.ts";
 import { GetReviewCommentsTool, ListPullRequestReviewsTool } from "./reviewComments.ts";
 import { SelectModeTool } from "./selectMode.ts";
-import { addTools } from "./shared.ts";
+import { addTools, initMcpContext, type McpInitContext } from "./shared.ts";
 
 /**
  * Find an available port starting from the given port
@@ -54,7 +54,11 @@ async function findAvailablePort(startPort: number): Promise<number> {
 /**
  * Start the MCP HTTP server and return the URL and close function
  */
-export async function startMcpHttpServer(): Promise<{ url: string; close: () => Promise<void> }> {
+export async function startMcpHttpServer(
+  state: McpInitContext
+): Promise<{ url: string; close: () => Promise<void> }> {
+  initMcpContext(state);
+
   const server = new FastMCP({
     name: ghPullfrogMcpName,
     version: "0.0.1",

mcp/shared.ts

@@ -2,46 +2,38 @@ import { Octokit } from "@octokit/rest";
 import type { StandardSchemaV1 } from "@standard-schema/spec";
 import type { FastMCP, Tool } from "fastmcp";
 import type { Payload } from "../external.ts";
+import type { Mode } from "../modes.ts";
 import { getGitHubInstallationToken, parseRepoContext, type RepoContext } from "../utils/github.ts";
 
-export interface ToolResult {
-  content: {
-    type: "text";
-    text: string;
-  }[];
-  isError?: boolean;
+export interface McpInitContext {
+  payload: Payload;
+  modes: Mode[];
 }
 
-export function getPayload(): Payload {
-  const payloadEnv = process.env.PULLFROG_PAYLOAD;
-  if (!payloadEnv) {
-    throw new Error("PULLFROG_PAYLOAD environment variable is required");
-  }
+let mcpInitContext: McpInitContext | undefined;
 
-  try {
-    return JSON.parse(payloadEnv) as Payload;
-  } catch (error) {
-    throw new Error(
-      `Failed to parse PULLFROG_PAYLOAD: ${error instanceof Error ? error.message : String(error)}`
-    );
-  }
+// this must be called on mcp server initialization
+export function initMcpContext(state: McpInitContext): void {
+  mcpInitContext = state;
+}
+
+export interface McpContext extends McpInitContext, RepoContext {
+  octokit: Octokit;
 }
 
 export function getMcpContext(): McpContext {
+  if (!mcpInitContext) {
+    throw new Error("MCP context not initialized. Call initializeMcpContext first.");
+  }
   return {
+    ...mcpInitContext,
     ...parseRepoContext(),
     octokit: new Octokit({
       auth: getGitHubInstallationToken(),
     }),
-    payload: getPayload(),
   };
 }
 
-export interface McpContext extends RepoContext {
-  octokit: Octokit;
-  payload: Payload;
-}
-
 export const tool = <const params>(toolDef: Tool<any, StandardSchemaV1<params>>) => toolDef;
 
 export const addTools = (server: FastMCP, tools: Tool<any, any>[]) => {
@@ -65,6 +57,14 @@ export const contextualize = <T>(
   };
 };
 
+export interface ToolResult {
+  content: {
+    type: "text";
+    text: string;
+  }[];
+  isError?: boolean;
+}
+
 const handleToolSuccess = (data: Record<string, any>): ToolResult => {
   return {
     content: [