> ## Documentation Index > Fetch the complete documentation index at: https://acaas.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Cookbook: a release notes amplifier > Build a complete Python tool that turns a flat changelog file into polished, emphasized release notes — using shout, scream, and emphasize together. This walkthrough builds a small but realistic Python program end-to-end. You take a plain-text changelog, generate a loud headline with `/v1/scream`, emphasize key words in each entry with `/v1/emphasize`, and write the result to a markdown file ready to paste into a release announcement. Along the way you handle authentication, rate limits, and errors the way you would in a real codebase. ## What you will build Given an input file `CHANGELOG.txt`: ```text theme={"dark"} the dashboard now loads twice as fast fixed a bug where exports occasionally truncated the last column added support for single sign-on via google workspace ``` The tool produces `RELEASE_NOTES.md`: ```markdown theme={"dark"} # RELEASE NOTES — APRIL 2026!!! - the **dashboard** now loads **twice as fast** - fixed a **bug** where exports occasionally **truncated** the last column - added support for **single sign-on** via **google workspace** ``` ## Prerequisites * Python 3.10 or newer. * `pip install requests`. * An ACAAS API key. For the demo, any non-empty string works. Set the key in your environment so it never lands in source control: ```bash theme={"dark"} export ACAAS_API_KEY="demo" ``` ## Step 1: A typed client wrapper Start with a thin `Client` class. It centralizes the base URL, the auth header, and the retry logic so the rest of the program reads like business logic. ```python client.py theme={"dark"} import os import time from dataclasses import dataclass import requests BASE_URL = "https://api.acaas.example.com" class ACAASError(Exception): """Raised when ACAAS returns an unrecoverable error.""" @dataclass class Client: api_key: str session: requests.Session @classmethod def from_env(cls) -> "Client": api_key = os.environ.get("ACAAS_API_KEY") if not api_key: raise ACAASError("ACAAS_API_KEY is not set") session = requests.Session() session.headers["X-API-Key"] = api_key session.headers["Content-Type"] = "application/json" return cls(api_key=api_key, session=session) def _post(self, path: str, body: dict) -> dict: for attempt in range(5): resp = self.session.post(f"{BASE_URL}{path}", json=body) if resp.status_code == 200: return resp.json() if resp.status_code == 429: status = self.session.get(f"{BASE_URL}/v1/rate-limits").json() time.sleep(status["resets_in_seconds"]) continue if resp.status_code in (401, 413, 422): raise ACAASError(f"{resp.status_code}: {resp.json().get('detail')}") time.sleep(2 ** attempt) # 1s, 2s, 4s, 8s, 16s raise ACAASError("ACAAS unavailable after retries") ``` The retry loop covers the three failure shapes you actually see: rate limits (wait for the window), client errors (don't retry — fix the input), and transient `5xx` (exponential backoff). ## Step 2: Endpoint methods Add one method per endpoint you need. Each is a one-liner over `_post`. ```python client.py (continued) theme={"dark"} def scream(self, text: str, *, intensity: int = 3) -> str: data = self._post("/v1/scream", {"text": text, "intensity": intensity}) return data["result"] def emphasize(self, text: str, *, ratio: float = 0.3) -> str: data = self._post("/v1/emphasize", {"text": text, "emphasis_ratio": ratio}) return data["result"] ``` Both endpoints return the same envelope, but you only need the `result` field for this tool. If you wanted to log which words were emphasized, return `data` instead and let the caller pick fields. ## Step 3: The amplifier With the client in place, the program logic is short. ```python amplify.py theme={"dark"} from datetime import date from pathlib import Path from client import Client def amplify(changelog_path: Path, output_path: Path, *, month: str) -> None: client = Client.from_env() raw_entries = [ line.strip() for line in changelog_path.read_text().splitlines() if line.strip() ] headline = client.scream(f"release notes — {month}", intensity=3) bulleted = [f"- {client.emphasize(entry, ratio=0.4)}" for entry in raw_entries] output_path.write_text( f"# {headline}\n\n" + "\n".join(bulleted) + "\n", encoding="utf-8", ) if __name__ == "__main__": today = date.today().strftime("%B %Y").lower() amplify( changelog_path=Path("CHANGELOG.txt"), output_path=Path("RELEASE_NOTES.md"), month=today, ) ``` Run it: ```bash theme={"dark"} python amplify.py ``` ## Step 4: Pacing for larger changelogs The version above issues one request per entry, plus one for the headline. For a fifty-line changelog that fits comfortably inside the 100-request demo window. For a five-hundred-line changelog it does not. Add proactive pacing inspired by the [rate limiting guide](/rate-limiting): ```python client.py (additional method) theme={"dark"} def pace_if_needed(self) -> None: status = self.session.get(f"{BASE_URL}/v1/rate-limits").json() if status["status"] == "at_limit": time.sleep(status["resets_in_seconds"]) elif status["status"] == "approaching_limit": remaining = max(status["requests_remaining"], 1) time.sleep(status["resets_in_seconds"] / remaining) ``` Then call it inside the loop: ```python amplify.py (modified) theme={"dark"} bulleted = [] for entry in raw_entries: client.pace_if_needed() bulleted.append(f"- {client.emphasize(entry, ratio=0.4)}") ``` Now the tool slows itself down before it spills `429`s into your logs. ## Step 5: Smoke-test before shipping A short test confirms each endpoint is reachable and your key works. ```python smoke.py theme={"dark"} from client import Client client = Client.from_env() assert "HELLO" in client.scream("hello"), "scream did not amplify" assert "**" in client.emphasize("this is a test of emphasis"), "emphasize did not bold" print("OK — ACAAS is reachable and the key is valid.") ``` Run it once before integrating into your release pipeline. ## What you learned * **One client, one session.** Reusing a `requests.Session` reuses TCP connections and centralizes headers. * **Retry the recoverable, raise the rest.** `429` and `5xx` are worth retrying; `401`, `413`, and `422` are not. * **Pace proactively when it matters.** For one-off scripts, `429` retries are fine. For batches, check status first and stretch the tail of the window evenly. * **Compose endpoints.** A useful tool rarely calls one endpoint — `/v1/scream` for the headline, `/v1/emphasize` for the body, and they speak the same envelope shape. ## Next steps Every status code, with copy-paste handler patterns. Quota mechanics, the `status` ladder, and proactive pacing. The endpoint that picks emphasis for you. Tune `emphasis_ratio`. Every endpoint, request, and response, in one place.