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Outlines

Outlines:结构化 JSON/regex/Pydantic LLM 生成。

Skill 元数据

来源可选 — 使用 aigenlabs skills install official/mlops/outlines 安装
路径optional-skills/mlops/inference/outlines
版本1.0.0
作者Orchestra Research
许可证MIT
依赖项outlines, transformers, vllm, pydantic
平台linux, macos, windows
标签Prompt Engineering, Outlines, Structured Generation, JSON Schema, Pydantic, Local Models, Grammar-Based Generation, vLLM, Transformers, Type Safety

参考:完整 SKILL.md

信息

以下是 AigenLabs 在触发此 skill 时加载的完整 skill 定义。这是 agent 在 skill 激活时看到的指令内容。

Outlines:结构化文本生成

何时使用此 Skill

在以下情况下使用 Outlines:

  • 保证有效的 JSON/XML/代码结构化生成
  • 使用 Pydantic 模型获得类型安全的输出
  • 支持本地模型(Transformers、llama.cpp、vLLM)
  • 通过零开销结构化生成最大化推理速度
  • 自动根据 JSON schema 生成
  • 在 grammar(语法)层面控制 token 采样

GitHub Stars:8,000+ | 来自:dottxt.ai(前身为 .txt)

安装

# 基础安装
pip install outlines

# 安装特定后端
pip install outlines transformers # Hugging Face 模型
pip install outlines llama-cpp-python # llama.cpp
pip install outlines vllm # vLLM 用于高吞吐量

快速开始

基础示例:分类

import outlines
from typing import Literal

# 加载模型
model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")

# 带类型约束的生成
prompt = "Sentiment of 'This product is amazing!': "
generator = outlines.generate.choice(model, ["positive", "negative", "neutral"])
sentiment = generator(prompt)

print(sentiment) # "positive"(保证为其中之一)

使用 Pydantic 模型

from pydantic import BaseModel
import outlines

class User(BaseModel):
name: str
age: int
email: str

model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")

# 生成结构化输出
prompt = "Extract user: John Doe, 30 years old, john@example.com"
generator = outlines.generate.json(model, User)
user = generator(prompt)

print(user.name) # "John Doe"
print(user.age) # 30
print(user.email) # "john@example.com"

核心概念

1. 受约束的 Token 采样

Outlines 使用有限状态机(FSM)在 logit 层面约束 token 生成。

工作原理:

  1. 将 schema(JSON/Pydantic/regex)转换为上下文无关文法(CFG)
  2. 将 CFG 转换为有限状态机(FSM)
  3. 在生成的每一步过滤无效 token
  4. 当只有一个有效 token 时快速前进

优势:

  • 零开销:过滤在 token 层面进行
  • 速度提升:通过确定性路径快速前进
  • 保证有效性:无效输出不可能产生
import outlines

# Pydantic 模型 -> JSON schema -> CFG -> FSM
class Person(BaseModel):
name: str
age: int

model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")

# 底层流程:
# 1. Person -> JSON schema
# 2. JSON schema -> CFG
# 3. CFG -> FSM
# 4. FSM 在生成过程中过滤 token

generator = outlines.generate.json(model, Person)
result = generator("Generate person: Alice, 25")

2. 结构化生成器

Outlines 为不同输出类型提供专用生成器。

Choice 生成器

# 多项选择
generator = outlines.generate.choice(
model,
["positive", "negative", "neutral"]
)

sentiment = generator("Review: This is great!")
# 结果:三个选项之一

JSON 生成器

from pydantic import BaseModel

class Product(BaseModel):
name: str
price: float
in_stock: bool

# 生成符合 schema 的有效 JSON
generator = outlines.generate.json(model, Product)
product = generator("Extract: iPhone 15, $999, available")

# 保证为有效的 Product 实例
print(type(product)) # <class '__main__.Product'>

Regex 生成器

# 生成匹配 regex 的文本
generator = outlines.generate.regex(
model,
r"[0-9]{3}-[0-9]{3}-[0-9]{4}" # 电话号码模式
)

phone = generator("Generate phone number:")
# 结果:"555-123-4567"(保证匹配模式)

整数/浮点数生成器

# 生成特定数值类型
int_generator = outlines.generate.integer(model)
age = int_generator("Person's age:") # 保证为整数

float_generator = outlines.generate.float(model)
price = float_generator("Product price:") # 保证为浮点数

3. 模型后端

Outlines 支持多种本地及基于 API 的后端。

Transformers(Hugging Face)

import outlines

# 从 Hugging Face 加载
model = outlines.models.transformers(
"microsoft/Phi-3-mini-4k-instruct",
device="cuda" # 或 "cpu"
)

# 与任意生成器配合使用
generator = outlines.generate.json(model, YourModel)

llama.cpp

# 加载 GGUF 模型
model = outlines.models.llamacpp(
"./models/llama-3.1-8b-instruct.Q4_K_M.gguf",
n_gpu_layers=35
)

generator = outlines.generate.json(model, YourModel)

vLLM(高吞吐量)

# 用于生产部署
model = outlines.models.vllm(
"meta-llama/Llama-3.1-8B-Instruct",
tensor_parallel_size=2 # 多 GPU
)

generator = outlines.generate.json(model, YourModel)

OpenAI(有限支持)

# 基础 OpenAI 支持
model = outlines.models.openai(
"gpt-4o-mini",
api_key="your-api-key"
)

# 注意:API 模型部分功能受限
generator = outlines.generate.json(model, YourModel)

4. Pydantic 集成

Outlines 对 Pydantic 提供一流支持,可自动进行 schema 转换。

基础模型

from pydantic import BaseModel, Field

class Article(BaseModel):
title: str = Field(description="Article title")
author: str = Field(description="Author name")
word_count: int = Field(description="Number of words", gt=0)
tags: list[str] = Field(description="List of tags")

model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")
generator = outlines.generate.json(model, Article)

article = generator("Generate article about AI")
print(article.title)
print(article.word_count) # 保证 > 0

嵌套模型

class Address(BaseModel):
street: str
city: str
country: str

class Person(BaseModel):
name: str
age: int
address: Address # 嵌套模型

generator = outlines.generate.json(model, Person)
person = generator("Generate person in New York")

print(person.address.city) # "New York"

Enum 与 Literal

from enum import Enum
from typing import Literal

class Status(str, Enum):
PENDING = "pending"
APPROVED = "approved"
REJECTED = "rejected"

class Application(BaseModel):
applicant: str
status: Status # 必须为枚举值之一
priority: Literal["low", "medium", "high"] # 必须为 literal 之一

generator = outlines.generate.json(model, Application)
app = generator("Generate application")

print(app.status) # Status.PENDING(或 APPROVED/REJECTED)

常见模式

模式 1:数据提取

from pydantic import BaseModel
import outlines

class CompanyInfo(BaseModel):
name: str
founded_year: int
industry: str
employees: int

model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")
generator = outlines.generate.json(model, CompanyInfo)

text = """
Apple Inc. was founded in 1976 in the technology industry.
The company employs approximately 164,000 people worldwide.
"""

prompt = f"Extract company information:\n{text}\n\nCompany:"
company = generator(prompt)

print(f"Name: {company.name}")
print(f"Founded: {company.founded_year}")
print(f"Industry: {company.industry}")
print(f"Employees: {company.employees}")

模式 2:分类

from typing import Literal
import outlines

model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")

# 二分类
generator = outlines.generate.choice(model, ["spam", "not_spam"])
result = generator("Email: Buy now! 50% off!")

# 多分类
categories = ["technology", "business", "sports", "entertainment"]
category_gen = outlines.generate.choice(model, categories)
category = category_gen("Article: Apple announces new iPhone...")

# 带置信度
class Classification(BaseModel):
label: Literal["positive", "negative", "neutral"]
confidence: float

classifier = outlines.generate.json(model, Classification)
result = classifier("Review: This product is okay, nothing special")

模式 3:结构化表单

class UserProfile(BaseModel):
full_name: str
age: int
email: str
phone: str
country: str
interests: list[str]

model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")
generator = outlines.generate.json(model, UserProfile)

prompt = """
Extract user profile from:
Name: Alice Johnson
Age: 28
Email: alice@example.com
Phone: 555-0123
Country: USA
Interests: hiking, photography, cooking
"""

profile = generator(prompt)
print(profile.full_name)
print(profile.interests) # ["hiking", "photography", "cooking"]

模式 4:多实体提取

class Entity(BaseModel):
name: str
type: Literal["PERSON", "ORGANIZATION", "LOCATION"]

class DocumentEntities(BaseModel):
entities: list[Entity]

model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")
generator = outlines.generate.json(model, DocumentEntities)

text = "Tim Cook met with Satya Nadella at Microsoft headquarters in Redmond."
prompt = f"Extract entities from: {text}"

result = generator(prompt)
for entity in result.entities:
print(f"{entity.name} ({entity.type})")

模式 5:代码生成

class PythonFunction(BaseModel):
function_name: str
parameters: list[str]
docstring: str
body: str

model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")
generator = outlines.generate.json(model, PythonFunction)

prompt = "Generate a Python function to calculate factorial"
func = generator(prompt)

print(f"def {func.function_name}({', '.join(func.parameters)}):")
print(f' """{func.docstring}"""')
print(f" {func.body}")

模式 6:批量处理

def batch_extract(texts: list[str], schema: type[BaseModel]):
"""从多段文本中提取结构化数据。"""
model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")
generator = outlines.generate.json(model, schema)

results = []
for text in texts:
result = generator(f"Extract from: {text}")
results.append(result)

return results

class Person(BaseModel):
name: str
age: int

texts = [
"John is 30 years old",
"Alice is 25 years old",
"Bob is 40 years old"
]

people = batch_extract(texts, Person)
for person in people:
print(f"{person.name}: {person.age}")

后端配置

Transformers

import outlines

# 基础用法
model = outlines.models.transformers("microsoft/Phi-3-mini-4k-instruct")

# GPU 配置
model = outlines.models.transformers(
"microsoft/Phi-3-mini-4k-instruct",
device="cuda",
model_kwargs={"torch_dtype": "float16"}
)

# 常用模型
model = outlines.models.transformers("meta-llama/Llama-3.1-8B-Instruct")
model = outlines.models.transformers("mistralai/Mistral-7B-Instruct-v0.3")
model = outlines.models.transformers("Qwen/Qwen2.5-7B-Instruct")

llama.cpp

# 加载 GGUF 模型
model = outlines.models.llamacpp(
"./models/llama-3.1-8b.Q4_K_M.gguf",
n_ctx=4096, # 上下文窗口
n_gpu_layers=35, # GPU 层数
n_threads=8 # CPU 线程数
)

# 完全 GPU 卸载
model = outlines.models.llamacpp(
"./models/model.gguf",
n_gpu_layers=-1 # 所有层在 GPU 上
)

vLLM(生产环境)

# 单 GPU
model = outlines.models.vllm("meta-llama/Llama-3.1-8B-Instruct")

# 多 GPU
model = outlines.models.vllm(
"meta-llama/Llama-3.1-70B-Instruct",
tensor_parallel_size=4 # 4 块 GPU
)

# 带量化
model = outlines.models.vllm(
"meta-llama/Llama-3.1-8B-Instruct",
quantization="awq" # 或 "gptq"
)

最佳实践

1. 使用具体类型

# ✅ 好:具体类型
class Product(BaseModel):
name: str
price: float # 非 str
quantity: int # 非 str
in_stock: bool # 非 str

# ❌ 差:全部用字符串
class Product(BaseModel):
name: str
price: str # 应为 float
quantity: str # 应为 int

2. 添加约束

from pydantic import Field

# ✅ 好:带约束
class User(BaseModel):
name: str = Field(min_length=1, max_length=100)
age: int = Field(ge=0, le=120)
email: str = Field(pattern=r"^[\w\.-]+@[\w\.-]+\.\w+$")

# ❌ 差:无约束
class User(BaseModel):
name: str
age: int
email: str

3. 对分类使用 Enum

# ✅ 好:固定集合使用 Enum
class Priority(str, Enum):
LOW = "low"
MEDIUM = "medium"
HIGH = "high"

class Task(BaseModel):
title: str
priority: Priority

# ❌ 差:自由格式字符串
class Task(BaseModel):
title: str
priority: str # 可以是任意值

4. 在 Prompt 中提供上下文

# ✅ 好:清晰的上下文
prompt = """
Extract product information from the following text.
Text: iPhone 15 Pro costs $999 and is currently in stock.
Product:
"""

# ❌ 差:上下文不足
prompt = "iPhone 15 Pro costs $999 and is currently in stock."

5. 处理可选字段

from typing import Optional

# ✅ 好:对不完整数据使用可选字段
class Article(BaseModel):
title: str # 必填
author: Optional[str] = None # 可选
date: Optional[str] = None # 可选
tags: list[str] = [] # 默认空列表

# 即使 author/date 缺失也能成功

与替代方案的对比

特性OutlinesInstructorGuidanceLMQL
Pydantic 支持✅ 原生✅ 原生❌ 无❌ 无
JSON Schema✅ 支持✅ 支持⚠️ 有限✅ 支持
Regex 约束✅ 支持❌ 无✅ 支持✅ 支持
本地模型✅ 完整⚠️ 有限✅ 完整✅ 完整
API 模型⚠️ 有限✅ 完整✅ 完整✅ 完整
零开销✅ 支持❌ 无⚠️ 部分✅ 支持
自动重试❌ 无✅ 支持❌ 无❌ 无
学习曲线

何时选择 Outlines:

  • 使用本地模型(Transformers、llama.cpp、vLLM)
  • 需要最大推理速度
  • 需要 Pydantic 模型支持
  • 需要零开销结构化生成
  • 需要控制 token 采样过程

何时选择替代方案:

  • Instructor:需要 API 模型并支持自动重试
  • Guidance:需要 token healing 和复杂工作流
  • LMQL:偏好声明式查询语法

性能特性

速度:

  • 零开销:结构化生成与无约束生成同样快速
  • 快速前进优化:跳过确定性 token
  • 比生成后验证方案快 1.2–2 倍

内存:

  • FSM 每个 schema 编译一次(已缓存)
  • 极低的运行时开销
  • 配合 vLLM 可实现高吞吐量

准确性:

  • 100% 有效输出(由 FSM 保证)
  • 无需重试循环
  • 确定性 token 过滤

资源

另请参阅

  • references/json_generation.md — 全面的 JSON 与 Pydantic 模式
  • references/backends.md — 后端专项配置
  • references/examples.md — 生产就绪示例