discovery-by-llm/backend/app/config.py

89 lines
3.6 KiB
Python

"""Typed application settings: the only reader of environment variables."""
from enum import StrEnum
from pydantic_settings import BaseSettings, SettingsConfigDict
class AppMode(StrEnum):
"""Runtime mode: live Spotify + Anthropic, or fixture-replay demo."""
LIVE = "live"
DEMO = "demo"
class Settings(BaseSettings):
"""Application settings, loaded from the environment or a .env file."""
model_config = SettingsConfigDict(env_file=".env", extra="ignore")
app_mode: AppMode = AppMode.DEMO
# Spotify application and OAuth. The redirect URI must exactly match a
# URI registered in the Spotify developer dashboard, port included.
spotify_client_id: str = ""
spotify_redirect_uri: str = "http://127.0.0.1:8888/callback"
spotify_api_base_url: str = "https://api.spotify.com/v1"
# Set behind TLS so the session cookie is never sent over plain HTTP.
session_cookie_secure: bool = False
# A pre-authorized refresh token installs a session at startup, so a
# hosted instance works without an interactive login.
spotify_seed_refresh_token: str = ""
# Spotify transport. A Retry-After above the cap fails the request
# instead of silently holding it open for seconds.
spotify_timeout_seconds: float = 10.0
spotify_retry_after_cap_seconds: float = 5.0
# LLM provider. Effort steers reasoning depth per call: intent is a
# recall task, reranking benefits from more deliberation.
anthropic_api_key: str = ""
llm_model: str = "claude-sonnet-5"
intent_effort: str = "low"
rerank_effort: str = "medium"
# Bound provider calls independently from the grounding deadline.
llm_timeout_seconds: float = 120.0
# Ceilings include adaptive thinking tokens, which is why they sit far
# above the size of the structured output itself.
intent_max_tokens: int = 16384
rerank_max_tokens: int = 16384
# Pipeline shape. candidate_count is the main call-1 latency lever and
# the hallucination budget: at "new to you" familiarity a large share of
# proposed tracks fails verification, so breadth keeps the pool filled.
# The buffer gives the reranker real choices beyond the shown count.
candidate_count: int = 35
rerank_count: int = 15
rerank_pool_buffer: int = 5
# Grounding. Search is capped at 10 results per call, so resolving is a
# fan-out; concurrency 6 stays far under the limiter (40 wide drew no
# 429s when measured). Below the floor the response is an honest error
# instead of a thin list. The similarity threshold rejects wrong tracks
# while tolerating punctuation and edition noise.
grounding_concurrency: int = 6
grounding_floor: int = 8
title_similarity_threshold: float = 0.82
request_deadline_seconds: float = 25.0
# In-process caches, single instance by design; a shared store is the
# first production step. Resolution entries are small, so the bound is
# generous; taste rarely shifts within a session.
resolution_cache_ttl_seconds: float = 3600.0
resolution_cache_max_entries: int = 2048
taste_profile_ttl_seconds: float = 900.0
# Demo replay paces recorded stream chunks so cards appear as they did live.
demo_chunk_delay_seconds: float = 0.05
# Taste profile fetch bounds: enough signal to describe a listener
# without paging through an entire library on session start.
top_items_limit: int = 50
saved_tracks_limit: int = 100
# Created playlists carry a fixed prefix so they can be found and
# removed in bulk afterwards.
playlist_name_prefix: str = "discovery-by-llm"
settings = Settings()