Agent skills

import tempfile
from pathlib import Path
 
SKILL = """---
name: expense-report
description: Fill in the company expense report from receipts. Use when the user mentions expenses, receipts or reimbursement.
---
# Expense report
1. Read each receipt and extract date, merchant, amount, currency.
2. Check the limits in references/limits.md.
3. Run scripts/make_report.py with the extracted rows.
"""
 
def frontmatter(text: str) -> dict:
    head = text.split("---")[1]                       # the YAML block between the first two ---
    return dict(line.split(": ", 1) for line in head.strip().splitlines())
 
with tempfile.TemporaryDirectory() as root:
    skill_dir = Path(root, "skills", "expense-report")
    (skill_dir / "references").mkdir(parents=True)
    (skill_dir / "SKILL.md").write_text(SKILL, encoding="utf8")
 
    # 1) DISCOVERY: at start-up the agent reads only name + description of every skill.
    index = {frontmatter(p.read_text(encoding="utf8"))["name"]: p
             for p in Path(root, "skills").glob("*/SKILL.md")}
    meta = frontmatter(index["expense-report"].read_text(encoding="utf8"))
    print("in context at start:", meta["name"], "-", meta["description"][:45] + "...")
 
    # 2) ACTIVATION: a matching task loads the full instructions into context.
    task = "Here are my receipts from the Berlin trip"
    if "receipts" in task.lower() and "receipts" in meta["description"].lower():
        body = index["expense-report"].read_text(encoding="utf8").split("---", 2)[2]
        print("loaded on demand  :", len(body.splitlines()), "lines of instructions")
    # 3) EXECUTION: the agent follows them, reading references/ or running scripts/ only if needed.

in context at start: expense-report - Fill in the company expense report from recei...
loaded on demand  : 5 lines of instructions