1import { existsSync, readdirSync, statSync } from "node:fs";
 2import { join } from "node:path";
 3import { Type } from "@sinclair/typebox";
 4import type { AgentTool } from "@mariozechner/pi-ai";
 5import { resolveToCwd } from "./path-utils.js";
 6import { DEFAULT_MAX_BYTES, formatSize, truncateHead } from "../../util/truncate.js";
 7
 8const DEFAULT_LIMIT = 500;
 9
10const LsSchema = Type.Object({
11  path: Type.Optional(Type.String({ description: "Directory to list (default: current directory)" })),
12  limit: Type.Optional(Type.Number({ description: "Maximum number of entries to return (default: 500)" })),
13});
14
15export const createLsTool = (workspacePath: string): AgentTool => ({
16  name: "ls",
17  label: "List Directory",
18  description: `List directory contents. Returns up to ${DEFAULT_LIMIT} entries and ${DEFAULT_MAX_BYTES / 1024} KB of output.`,
19  parameters: LsSchema as any,
20  execute: async (_toolCallId: string, params: any) => {
21    const resolved = resolveToCwd(params.path || ".", workspacePath);
22
23    if (!existsSync(resolved)) {
24      throw new Error(`Path does not exist: ${params.path || "."}`);
25    }
26
27    const stats = statSync(resolved);
28    if (!stats.isDirectory()) {
29      throw new Error(`Not a directory: ${params.path || "."}`);
30    }
31
32    const entries = readdirSync(resolved);
33    entries.sort((a, b) => a.localeCompare(b, undefined, { sensitivity: "base" }));
34
35    const effectiveLimit = params.limit ?? DEFAULT_LIMIT;
36    const limited = entries.slice(0, effectiveLimit);
37    const entryLimitReached = entries.length > effectiveLimit;
38
39    const lines = limited.map((entry) => {
40      const entryPath = join(resolved, entry);
41      try {
42        const entryStat = statSync(entryPath);
43        return entryStat.isDirectory() ? `${entry}/` : entry;
44      } catch {
45        return entry;
46      }
47    });
48
49    if (lines.length === 0) {
50      return {
51        content: [{ type: "text", text: "(empty directory)" }],
52        details: {},
53      };
54    }
55
56    const rawOutput = lines.join("\n");
57    const truncation = truncateHead(rawOutput, { maxLines: Number.MAX_SAFE_INTEGER });
58
59    const notices: string[] = [];
60    if (entryLimitReached) {
61      notices.push(`Entry limit reached: showing ${effectiveLimit} of ${entries.length} entries.`);
62    }
63    if (truncation.truncated) {
64      notices.push(
65        `Output truncated: showing ${formatSize(truncation.outputBytes)} of ${formatSize(truncation.totalBytes)}.`,
66      );
67    }
68
69    let output = truncation.content;
70    if (notices.length > 0) {
71      output += `\n\n[${notices.join(" ")}]`;
72    }
73
74    return {
75      content: [{ type: "text", text: output }],
76      details: {
77        ...(truncation.truncated ? { truncation } : {}),
78        ...(entryLimitReached ? { entryLimitReached: true } : {}),
79      },
80    };
81  },
82});