fix(mcp): keep codegraph_explore loaded in Claude Code and Copilot CLI (#1696)

Claude Code defers every MCP tool behind ToolSearch by default, so a fresh session sees only the tool name until the model searches for it. The explore tool now carries `_meta: { "anthropic/alwaysLoad": true }`, which exempts it on existing installs, and the Claude Code installer target writes `alwaysLoad: true` on the server entry (re-running install adds the key to an older entry). Copilot CLI tool search holds MCP tools back the same way once ~30 tools are connected, so its entry carries `deferTools: "never"`.

src/installer/targets/claude.ts

@@ -41,6 +41,18 @@ import {
   CODEGRAPH_SECTION_START,
 } from '../instructions-template';
 
+/**
+ * The shared stdio entry plus `alwaysLoad: true`, Claude Code's exemption from
+ * tool-search deferral (https://code.claude.com/docs/en/mcp#exempt-a-server-from-deferral).
+ * `codegraph_explore` carries the same flag in its `_meta`, which covers an
+ * entry written before this key; the entry-level key additionally makes
+ * Claude Code wait for this server's tools at startup, so they are in the
+ * first prompt rather than listed after the server connects in the background.
+ */
+function getClaudeMcpServerConfig() {
+  return { ...getMcpServerConfig(), alwaysLoad: true };
+}
+
 function configDir(loc: Location): string {
   return loc === 'global'
     ? path.join(os.homedir(), '.claude')
@@ -211,7 +223,7 @@ class ClaudeCodeTarget implements AgentTarget {
 
   printConfig(loc: Location): string {
     const target = mcpJsonPath(loc);
-    const snippet = JSON.stringify({ mcpServers: { codegraph: getMcpServerConfig() } }, null, 2);
+    const snippet = JSON.stringify({ mcpServers: { codegraph: getClaudeMcpServerConfig() } }, null, 2);
     return `# Add to ${target}\n\n${snippet}\n`;
   }
 
@@ -231,7 +243,7 @@ export function writeMcpEntry(loc: Location): WriteResult['files'][number] {
   const file = mcpJsonPath(loc);
   const existing = readJsonFile(file);
   const before = existing.mcpServers?.codegraph;
-  const after = getMcpServerConfig();
+  const after = getClaudeMcpServerConfig();
 
   if (jsonDeepEqual(before, after)) {
     // Already exactly what we'd write — preserve byte-identical file.

src/installer/targets/copilot-cli.ts

@@ -95,9 +95,15 @@ function copilotOnPath(): boolean {
   return false;
 }
 
-function buildCopilotMcpConfig(): { type: string; command: string; args: string[]; tools: string[] } {
+/**
+ * The shared stdio entry, every tool allowed, and `deferTools: 'never'`: Copilot CLI's tool
+ * search (on by default from ~30 connected tools on Claude and GPT-5.4+ models) otherwise holds
+ * MCP tools back until the model searches for them, so `codegraph_explore` would be a name the
+ * model has to go looking for before it can follow the "call it instead of Read" instruction.
+ */
+function buildCopilotMcpConfig(): { type: string; command: string; args: string[]; tools: string[]; deferTools: 'never' } {
   const base = getMcpServerConfig();
-  return { ...base, tools: ['*'] };
+  return { ...base, tools: ['*'], deferTools: 'never' };
 }
 
 class CopilotCliTarget implements AgentTarget {

src/mcp/tools.ts

@@ -942,6 +942,12 @@ export interface ToolDefinition {
   };
   /** Behavioral hints for clients (see {@link ToolAnnotations}). */
   annotations?: ToolAnnotations;
+  /**
+   * MCP `_meta` on the tool definition. `anthropic/alwaysLoad: true` makes
+   * Claude Code load the tool at session start instead of deferring it behind
+   * its tool search (https://code.claude.com/docs/en/mcp#exempt-a-server-from-deferral).
+   */
+  _meta?: Record<string, unknown>;
 }
 
 /**
@@ -1196,6 +1202,9 @@ export const tools: ToolDefinition[] = [
       required: ['query'],
     },
     annotations: READ_ONLY_ANNOTATIONS,
+    // Loaded from the first prompt in Claude Code, which otherwise defers every
+    // MCP tool behind a ToolSearch step (#1696).
+    _meta: { 'anthropic/alwaysLoad': true },
   },
   {
     name: 'codegraph_status',