Fix Codex smoke gateway auth by syncing converted config into writable CODEX_HOME

pkg/workflow/codex_engine.go

@@ -463,9 +463,7 @@ func (e *CodexEngine) expandNeutralToolsToCodexToolsFromMap(tools map[string]any
 	return result.ToMap()
 }
 
-// renderShellEnvironmentPolicy generates the [shell_environment_policy] section for config.toml
-// This controls which environment variables are passed through to MCP servers for security
-func (e *CodexEngine) renderShellEnvironmentPolicy(yaml *strings.Builder, tools map[string]any, mcpTools []string, workflowData *WorkflowData) {
+func (e *CodexEngine) getShellEnvironmentPolicyVars(tools map[string]any, mcpTools []string) []string {
 	// Collect all environment variables needed by MCP servers
 	envVars := make(map[string]bool)
 
@@ -509,13 +507,20 @@ func (e *CodexEngine) renderShellEnvironmentPolicy(yaml *strings.Builder, tools
 		}
 	}
 
-	// Sort environment variable names for consistent output
 	var sortedEnvVars []string
 	for envVar := range envVars {
 		sortedEnvVars = append(sortedEnvVars, envVar)
 	}
 	sort.Strings(sortedEnvVars)
 
+	return sortedEnvVars
+}
+
+// renderShellEnvironmentPolicy generates the [shell_environment_policy] section for config.toml
+// This controls which environment variables are passed through to MCP servers for security
+func (e *CodexEngine) renderShellEnvironmentPolicy(yaml *strings.Builder, tools map[string]any, mcpTools []string) {
+	sortedEnvVars := e.getShellEnvironmentPolicyVars(tools, mcpTools)
+
 	// Render [shell_environment_policy] section
 	yaml.WriteString("          \n")
 	yaml.WriteString("          [shell_environment_policy]\n")
@@ -530,6 +535,21 @@ func (e *CodexEngine) renderShellEnvironmentPolicy(yaml *strings.Builder, tools
 	yaml.WriteString("]\n")
 }
 
+func (e *CodexEngine) renderShellEnvironmentPolicyToml(yaml *strings.Builder, tools map[string]any, mcpTools []string, indent string) {
+	sortedEnvVars := e.getShellEnvironmentPolicyVars(tools, mcpTools)
+
+	yaml.WriteString(indent + "[shell_environment_policy]\n")
+	yaml.WriteString(indent + "inherit = \"core\"\n")
+	yaml.WriteString(indent + "include_only = [")
+	for i, envVar := range sortedEnvVars {
+		if i > 0 {
+			yaml.WriteString(", ")
+		}
+		yaml.WriteString("\"" + envVar + "\"")
+	}
+	yaml.WriteString("]\n")
+}
+
 // RenderMCPConfig is implemented in codex_mcp.go
 
 // renderCodexMCPConfig is implemented in codex_mcp.go

pkg/workflow/codex_engine_test.go

@@ -250,6 +250,19 @@ func TestCodexEngineRenderMCPConfig(t *testing.T) {
 				"}",
 				"}",
 				"GH_AW_MCP_CONFIG_NORM_EOF",
+				"",
+				"# Sync converter output to writable CODEX_HOME for Codex",
+				"mkdir -p /tmp/gh-aw/mcp-config",
+				"cat > \"/tmp/gh-aw/mcp-config/config.toml\" << GH_AW_CODEX_SHELL_POLICY_NORM_EOF",
+				"[shell_environment_policy]",
+				"inherit = \"core\"",
+				"include_only = [\"CODEX_API_KEY\", \"GITHUB_PERSONAL_ACCESS_TOKEN\", \"HOME\", \"OPENAI_API_KEY\", \"PATH\"]",
+				"GH_AW_CODEX_SHELL_POLICY_NORM_EOF",
+				"cat \"${RUNNER_TEMP}/gh-aw/mcp-config/config.toml\" >> \"/tmp/gh-aw/mcp-config/config.toml\"",
+				"chmod 600 \"/tmp/gh-aw/mcp-config/config.toml\"",
+				"mkdir -p \"${CODEX_HOME}\"",
+				"cp \"/tmp/gh-aw/mcp-config/config.toml\" \"${CODEX_HOME}/config.toml\"",
+				"chmod 600 \"${CODEX_HOME}/config.toml\"",
 			},
 		},
 	}

pkg/workflow/codex_mcp.go

@@ -37,7 +37,7 @@ func (e *CodexEngine) RenderMCPConfig(yaml *strings.Builder, tools map[string]an
 
 	// Add shell environment policy to control which environment variables are passed through
 	// This is a security feature to prevent accidental exposure of secrets
-	e.renderShellEnvironmentPolicy(yaml, tools, mcpTools, workflowData)
+	e.renderShellEnvironmentPolicy(yaml, tools, mcpTools)
 
 	// Expand neutral tools (like playwright: null) to include the copilot agent tools
 	expandedTools := e.expandNeutralToolsToCodexToolsFromMap(tools)
@@ -99,11 +99,44 @@ func (e *CodexEngine) RenderMCPConfig(yaml *strings.Builder, tools map[string]an
 	yaml.WriteString("          # Generate JSON config for MCP gateway\n")
 
 	// Gateway uses JSON format without Copilot-specific fields and multi-line args
-	return renderStandardJSONMCPConfig(yaml, tools, mcpTools, workflowData,
+	if err := renderStandardJSONMCPConfig(yaml, tools, mcpTools, workflowData,
 		"${RUNNER_TEMP}/gh-aw/mcp-config/mcp-servers.json", false, false,
 		func(yaml *strings.Builder, toolName string, toolConfig map[string]any, isLast bool) error {
 			return e.renderCodexJSONMCPConfigWithContext(yaml, toolName, toolConfig, isLast, workflowData)
-		}, nil)
+		}, nil); err != nil {
+		return err
+	}
+
+	// start_mcp_gateway.cjs converts the gateway output and writes Codex config to
+	// ${RUNNER_TEMP}/gh-aw/mcp-config/config.toml. Codex reads config from
+	// $CODEX_HOME/config.toml, so copy the converted config into writable CODEX_HOME
+	// and prepend shell policy (converter output does not include this section).
+	yaml.WriteString("          \n")
+	yaml.WriteString("          # Sync converter output to writable CODEX_HOME for Codex\n")
+	yaml.WriteString("          mkdir -p /tmp/gh-aw/mcp-config\n")
+
+	shellPolicyDelimiter := GenerateHeredocDelimiterFromSeed("CODEX_SHELL_POLICY", workflowData.FrontmatterHash)
+	yaml.WriteString("          cat > \"/tmp/gh-aw/mcp-config/config.toml\" << " + shellPolicyDelimiter + "\n")
+	e.renderShellEnvironmentPolicyToml(yaml, tools, mcpTools, "          ")
+	yaml.WriteString("          " + shellPolicyDelimiter + "\n")
+	yaml.WriteString("          cat \"${RUNNER_TEMP}/gh-aw/mcp-config/config.toml\" >> \"/tmp/gh-aw/mcp-config/config.toml\"\n")
+	if workflowData.EngineConfig != nil && strings.TrimSpace(workflowData.EngineConfig.Config) != "" {
+		customConfigDelimiter := GenerateHeredocDelimiterFromSeed("CODEX_CUSTOM_CONFIG", workflowData.FrontmatterHash)
+		yaml.WriteString("          \n")
+		yaml.WriteString("          # Append engine-level custom Codex config\n")
+		yaml.WriteString("          cat >> \"/tmp/gh-aw/mcp-config/config.toml\" << " + customConfigDelimiter + "\n")
+		yaml.WriteString(workflowData.EngineConfig.Config)
+		if !strings.HasSuffix(workflowData.EngineConfig.Config, "\n") {
+			yaml.WriteString("\n")
+		}
+		yaml.WriteString("          " + customConfigDelimiter + "\n")
+	}
+	yaml.WriteString("          chmod 600 \"/tmp/gh-aw/mcp-config/config.toml\"\n")
+	yaml.WriteString("          mkdir -p \"${CODEX_HOME}\"\n")
+	yaml.WriteString("          cp \"/tmp/gh-aw/mcp-config/config.toml\" \"${CODEX_HOME}/config.toml\"\n")
+	yaml.WriteString("          chmod 600 \"${CODEX_HOME}/config.toml\"\n")
+
+	return nil
 }
 
 // renderCodexMCPConfigWithContext generates custom MCP server configuration for a single tool in codex workflow config.toml