1/**
  2 * Agent discovery and configuration
  3 */
  4
  5import * as fs from "node:fs";
  6import * as os from "node:os";
  7import * as path from "node:path";
  8import { parseFrontmatter } from "@earendil-works/pi-coding-agent";
  9
 10export type AgentScope = "user" | "project" | "both";
 11
 12export interface AgentConfig {
 13	name: string;
 14	description: string;
 15	tools?: string[];
 16	model?: string;
 17	provider?: string;
 18	systemPrompt: string;
 19	source: "user" | "project";
 20	filePath: string;
 21}
 22
 23export interface AgentDiscoveryResult {
 24	agents: AgentConfig[];
 25	projectAgentsDir: string | null;
 26}
 27
 28function loadAgentsFromDir(dir: string, source: "user" | "project"): AgentConfig[] {
 29	const agents: AgentConfig[] = [];
 30
 31	if (!fs.existsSync(dir)) {
 32		return agents;
 33	}
 34
 35	let entries: fs.Dirent[];
 36	try {
 37		entries = fs.readdirSync(dir, { withFileTypes: true });
 38	} catch {
 39		return agents;
 40	}
 41
 42	for (const entry of entries) {
 43		if (!entry.name.endsWith(".md")) continue;
 44		if (!entry.isFile() && !entry.isSymbolicLink()) continue;
 45
 46		const filePath = path.join(dir, entry.name);
 47		let content: string;
 48		try {
 49			content = fs.readFileSync(filePath, "utf-8");
 50		} catch {
 51			continue;
 52		}
 53
 54		const { frontmatter, body } = parseFrontmatter<Record<string, string>>(content);
 55
 56		if (!frontmatter.name || !frontmatter.description) {
 57			continue;
 58		}
 59
 60		const tools = frontmatter.tools
 61			?.split(",")
 62			.map((t: string) => t.trim())
 63			.filter(Boolean);
 64
 65		agents.push({
 66			name: frontmatter.name,
 67			description: frontmatter.description,
 68			tools: tools && tools.length > 0 ? tools : undefined,
 69			model: frontmatter.model,
 70			provider: frontmatter.provider,
 71			systemPrompt: body,
 72			source,
 73			filePath,
 74		});
 75	}
 76
 77	return agents;
 78}
 79
 80function isDirectory(p: string): boolean {
 81	try {
 82		return fs.statSync(p).isDirectory();
 83	} catch {
 84		return false;
 85	}
 86}
 87
 88function findNearestProjectAgentsDir(cwd: string): string | null {
 89	let currentDir = cwd;
 90	while (true) {
 91		const candidate = path.join(currentDir, ".pi", "agents");
 92		if (isDirectory(candidate)) return candidate;
 93
 94		const parentDir = path.dirname(currentDir);
 95		if (parentDir === currentDir) return null;
 96		currentDir = parentDir;
 97	}
 98}
 99
100export function discoverAgents(cwd: string, scope: AgentScope): AgentDiscoveryResult {
101	const userDir = path.join(os.homedir(), ".pi", "agent", "agents");
102	const projectAgentsDir = findNearestProjectAgentsDir(cwd);
103
104	const userAgents = scope === "project" ? [] : loadAgentsFromDir(userDir, "user");
105	const projectAgents = scope === "user" || !projectAgentsDir ? [] : loadAgentsFromDir(projectAgentsDir, "project");
106
107	const agentMap = new Map<string, AgentConfig>();
108
109	if (scope === "both") {
110		for (const agent of userAgents) agentMap.set(agent.name, agent);
111		for (const agent of projectAgents) agentMap.set(agent.name, agent);
112	} else if (scope === "user") {
113		for (const agent of userAgents) agentMap.set(agent.name, agent);
114	} else {
115		for (const agent of projectAgents) agentMap.set(agent.name, agent);
116	}
117
118	return { agents: Array.from(agentMap.values()), projectAgentsDir };
119}
120
121export function formatAgentList(agents: AgentConfig[], maxItems: number): { text: string; remaining: number } {
122	if (agents.length === 0) return { text: "none", remaining: 0 };
123	const listed = agents.slice(0, maxItems);
124	const remaining = agents.length - listed.length;
125	return {
126		text: listed.map((a) => `${a.name} (${a.source}): ${a.description}`).join("; "),
127		remaining,
128	};
129}