Class: LLM::Agent

Inherits:
Object
  • Object
show all
Defined in:
lib/llm/agent.rb

Overview

LLM::Agent provides a class-level DSL for defining reusable, preconfigured assistants with defaults for model, tools, schema, and instructions.

It wraps the same stateful runtime surface as LLM::Context: message history, usage, persistence, streaming parameters, and provider-backed requests still flow through an underlying context. The defining behavior of an agent is that it automatically resolves pending tool calls for you during ‘talk` and `respond`, instead of leaving tool loops to the caller.

Notes:

  • Instructions are injected only on the first request.

  • An agent automatically executes tool loops (unlike LLM::Context).

  • Tool loop execution can be configured with ‘concurrency :call`, `:thread`, `:task`, `:fiber`, `:ractor`, or a list of queued task types such as `[:thread, :ractor]`.

Examples:

class SystemAdmin < LLM::Agent
  model "gpt-4.1-nano"
  instructions "You are a Linux system admin"
  tools Shell
  schema Result
end

llm = LLM.openai(key: ENV["KEY"])
agent = SystemAdmin.new(llm)
agent.talk("Run 'date'")

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(llm, params = {}) ⇒ Agent

Returns a new instance of Agent.

Parameters:

  • provider (LLM::Provider) —

    A provider

  • params (Hash) (defaults to: {}) —

    The parameters to maintain throughout the conversation. Any parameter the provider supports can be included and not only those listed here.

Options Hash (params):

  • :model (String) —

    Defaults to the provider’s default model

  • :tools (Array<LLM::Function>, nil) —

    Defaults to nil

  • :skills (Array<String>, nil) —

    Defaults to nil

  • :schema (#to_json, nil) —

    Defaults to nil

  • :concurrency (Symbol, Array<Symbol>, nil) —

    Defaults to the agent class concurrency



127
128
129
130
131
132
 
# File 'lib/llm/agent.rb', line 127

def initialize(llm, params = {})
  defaults = {model: self.class.model, tools: self.class.tools, skills: self.class.skills, schema: self.class.schema}.compact
  @concurrency = params.delete(:concurrency) || self.class.concurrency
  @llm = llm
  @ctx = LLM::Context.new(llm, defaults.merge(params))
end

Instance Attribute Details

#llm ⇒ LLM::Provider (readonly)

Returns a provider

Returns:



38
39
40
 
# File 'lib/llm/agent.rb', line 38

def llm
  @llm
end

Class Method Details

.concurrency(concurrency = nil) ⇒ Symbol, ...

Set or get the tool execution concurrency.

Parameters:

  • concurrency (Symbol, Array<Symbol>, nil) (defaults to: nil) —

    Controls how pending tool loops are executed:

    • ‘:call`: sequential calls

    • ‘:thread`: concurrent threads

    • ‘:task`: concurrent async tasks

    • ‘:fiber`: concurrent raw fibers

    • ‘:ractor`: concurrent Ruby ractors for class-based tools; MCP tools are not supported, and this mode is especially useful for CPU-bound tool work

    • ‘[:thread, :ractor]`: the possible concurrency strategies to wait on, in the given order. This is useful for mixed tool sets or when work may have been spawned with more than one concurrency strategy.

Returns:

  • (Symbol, Array<Symbol>, nil) 


110
111
112
113
 
# File 'lib/llm/agent.rb', line 110

def self.concurrency(concurrency = nil)
  return @concurrency if concurrency.nil?
  @concurrency = concurrency
end

.instructions(instructions = nil) ⇒ String?

Set or get the default instructions

Parameters:

  • instructions (String, nil) (defaults to: nil) —

    The system instructions

Returns:

  • (String, nil) —

    Returns the current instructions when no argument is provided



90
91
92
93
 
# File 'lib/llm/agent.rb', line 90

def self.instructions(instructions = nil)
  return @instructions if instructions.nil?
  @instructions = instructions
end

.model(model = nil) ⇒ String?

Set or get the default model

Parameters:

  • model (String, nil) (defaults to: nil) —

    The model identifier

Returns:

  • (String, nil) —

    Returns the current model when no argument is provided



46
47
48
49
 
# File 'lib/llm/agent.rb', line 46

def self.model(model = nil)
  return @model if model.nil?
  @model = model
end

.schema(schema = nil) ⇒ #to_json?

Set or get the default schema

Parameters:

  • schema (#to_json, nil) (defaults to: nil) —

    The schema

Returns:

  • (#to_json, nil) —

    Returns the current schema when no argument is provided



79
80
81
82
 
# File 'lib/llm/agent.rb', line 79

def self.schema(schema = nil)
  return @schema if schema.nil?
  @schema = schema
end

.skills(*skills) ⇒ Array<String>?

Set or get the default skills

Parameters:

  • skills (Array<String>, nil) —

    One or more skill directories

Returns:

  • (Array<String>, nil) —

    Returns the current skills when no argument is provided



68
69
70
71
 
# File 'lib/llm/agent.rb', line 68

def self.skills(*skills)
  return @skills if skills.empty?
  @skills = skills.flatten
end

.tools(*tools) ⇒ Array<LLM::Function>

Set or get the default tools

Parameters:

Returns:

  • (Array<LLM::Function>) —

    Returns the current tools when no argument is provided



57
58
59
60
 
# File 'lib/llm/agent.rb', line 57

def self.tools(*tools)
  return @tools || [] if tools.empty?
  @tools = tools.flatten
end

Instance Method Details

#call ⇒ Object

Returns:

See Also:



206
207
208
 
# File 'lib/llm/agent.rb', line 206

def call(...)
  @ctx.call(...)
end

#concurrency ⇒ Symbol, ...

Returns the configured tool execution concurrency.

Returns:

  • (Symbol, Array<Symbol>, nil) 


290
291
292
 
# File 'lib/llm/agent.rb', line 290

def concurrency
  @concurrency
end

#context_window ⇒ Integer

Returns:

  • (Integer)

See Also:



304
305
306
 
# File 'lib/llm/agent.rb', line 304

def context_window
  @ctx.context_window
end

#cost ⇒ LLM::Cost

Returns:

See Also:



297
298
299
 
# File 'lib/llm/agent.rb', line 297

def cost
  @ctx.cost
end

#deserialize(**kw) ⇒ Object Also known as: restore 



339
340
341
 
# File 'lib/llm/agent.rb', line 339

def deserialize(**kw)
  @ctx.deserialize(**kw)
end

#functions ⇒ Array<LLM::Function>

Returns:



192
193
194
 
# File 'lib/llm/agent.rb', line 192

def functions
  @ctx.functions
end

#image_url(url) ⇒ LLM::Object

Returns a tagged object

Parameters:

  • url (String) —

    The URL

Returns:



245
246
247
 
# File 'lib/llm/agent.rb', line 245

def image_url(url)
  @ctx.image_url(url)
end

#inspect ⇒ String

Returns:

  • (String) 


323
324
325
326
 
# File 'lib/llm/agent.rb', line 323

def inspect
  "#<#{self.class.name}:0x#{object_id.to_s(16)} " \
  "@llm=#{@llm.class}, @mode=#{mode.inspect}, @messages=#{messages.inspect}>"
end

#interrupt! ⇒ nil Also known as: cancel!

Interrupt the active request, if any.

Returns:

  • (nil) 


226
227
228
 
# File 'lib/llm/agent.rb', line 226

def interrupt!
  @ctx.interrupt!
end

#local_file(path) ⇒ LLM::Object

Returns a tagged object

Parameters:

  • path (String) —

    The path

Returns:



254
255
256
 
# File 'lib/llm/agent.rb', line 254

def local_file(path)
  @ctx.local_file(path)
end

#messages ⇒ LLM::Buffer<LLM::Message>

Returns:



186
187
188
 
# File 'lib/llm/agent.rb', line 186

def messages
  @ctx.messages
end

#mode ⇒ Symbol

Returns:

  • (Symbol) 


283
284
285
 
# File 'lib/llm/agent.rb', line 283

def mode
  @ctx.mode
end

#model ⇒ String

Returns the model an Agent is actively using

Returns:

  • (String) 


277
278
279
 
# File 'lib/llm/agent.rb', line 277

def model
  @ctx.model
end

#prompt(&b) ⇒ LLM::Prompt Also known as: build_prompt

Parameters:

  • b (Proc) —

    A block that composes messages. If it takes one argument, it receives the prompt object. Otherwise it runs in prompt context.

Returns:

See Also:



235
236
237
 
# File 'lib/llm/agent.rb', line 235

def prompt(&b)
  @ctx.prompt(&b)
end

#remote_file(res) ⇒ LLM::Object

Returns a tagged object

Parameters:

Returns:



263
264
265
 
# File 'lib/llm/agent.rb', line 263

def remote_file(res)
  @ctx.remote_file(res)
end

#respond(prompt, params = {}) ⇒ LLM::Response

Note:

Not all LLM providers support this API

Maintain a conversation via the responses API. This method immediately sends a request to the LLM and returns the response.

Examples:

llm = LLM.openai(key: ENV["KEY"])
agent = LLM::Agent.new(llm)
res = agent.respond("What is the capital of France?")
puts res.output_text

Parameters:

  • params (Hash) (defaults to: {}) —

    The params passed to the provider, including optional :stream, :tools, :schema etc.

  • prompt (String) —

    The input prompt to be completed

Options Hash (params):

  • :tool_attempts (Integer) —

    The maxinum number of tool call iterations (default 10)

Returns:

  • (LLM::Response) —

    Returns the LLM’s response for this turn.

Raises:



173
174
175
176
177
178
179
180
181
182
 
# File 'lib/llm/agent.rb', line 173

def respond(prompt, params = {})
  max = Integer(params.delete(:tool_attempts) || 10)
  res = @ctx.respond(apply_instructions(prompt), params)
  max.times do
    break if @ctx.functions.empty?
    res = @ctx.respond(call_functions, params)
  end
  raise LLM::ToolLoopError, "pending tool calls remain" unless @ctx.functions.empty?
  res
end

#returns ⇒ Array<LLM::Function::Return>

Returns:

See Also:



199
200
201
 
# File 'lib/llm/agent.rb', line 199

def returns
  @ctx.returns
end

#serialize(**kw) ⇒ void Also known as: save

This method returns an undefined value.



331
332
333
 
# File 'lib/llm/agent.rb', line 331

def serialize(**kw)
  @ctx.serialize(**kw)
end

#talk(prompt, params = {}) ⇒ LLM::Response Also known as: chat

Maintain a conversation via the chat completions API. This method immediately sends a request to the LLM and returns the response.

Examples:

llm = LLM.openai(key: ENV["KEY"])
agent = LLM::Agent.new(llm)
response = agent.talk("Hello, what is your name?")
puts response.choices[0].content

Parameters:

  • params (Hash) (defaults to: {}) —

    The params passed to the provider, including optional :stream, :tools, :schema etc.

  • prompt (String) —

    The input prompt to be completed

Options Hash (params):

  • :tool_attempts (Integer) —

    The maxinum number of tool call iterations (default 10)

Returns:

  • (LLM::Response) —

    Returns the LLM’s response for this turn.

Raises:



147
148
149
150
151
152
153
154
155
156
 
# File 'lib/llm/agent.rb', line 147

def talk(prompt, params = {})
  max = Integer(params.delete(:tool_attempts) || 10)
  res = @ctx.talk(apply_instructions(prompt), params)
  max.times do
    break if @ctx.functions.empty?
    res = @ctx.talk(call_functions, params)
  end
  raise LLM::ToolLoopError, "pending tool calls remain" unless @ctx.functions.empty?
  res
end

#to_h ⇒ Hash

Returns:

  • (Hash)

See Also:



311
312
313
 
# File 'lib/llm/agent.rb', line 311

def to_h
  @ctx.to_h
end

#to_json ⇒ String

Returns:

  • (String) 


317
318
319
 
# File 'lib/llm/agent.rb', line 317

def to_json(...)
  to_h.to_json(...)
end

#tracer ⇒ LLM::Tracer

Returns an LLM tracer

Returns:



270
271
272
 
# File 'lib/llm/agent.rb', line 270

def tracer
  @ctx.tracer
end

#usage ⇒ LLM::Object

Returns:



219
220
221
 
# File 'lib/llm/agent.rb', line 219

def usage
  @ctx.usage
end

#wait ⇒ Array<LLM::Function::Return>

Returns:

See Also:



213
214
215
 
# File 'lib/llm/agent.rb', line 213

def wait(...)
  @ctx.wait(...)
end