TextMessage¶

Text message from system, user, or assistant.

Class: `RobotLab::TextMessage`¶

message = TextMessage.new(role: "assistant", content: "Hello! How can I help you today?")

Constructor¶

TextMessage.new(role:, content:, stop_reason: nil)

Parameters:

Name	Type	Description
`role`	`String`	Message role ("system", "user", or "assistant")
`content`	`String`	The text content
`stop_reason`	`String`, `nil`	Stop reason ("stop" or "tool")

Attributes¶

content¶

message.content  # => String

The text content.

role¶

message.role  # => "assistant"

Returns a String: "system", "user", or "assistant".

type¶

message.type  # => "text"

Always returns "text".

stop_reason¶

message.stop_reason  # => "stop" or nil

The stop reason, if any.

Methods¶

to_h¶

message.to_h  # => Hash

Hash representation. Inherited from Message#to_h, which ends in .compact — a nil stop_reason is omitted rather than serialized as nil.

Returns:

TextMessage.new(role: "assistant", content: "Hello! How can I help you today?").to_h
# => { type: "text", role: "assistant", content: "Hello! How can I help you today?" }

TextMessage.new(role: "assistant", content: "Done.", stop_reason: "stop").to_h
# => { type: "text", role: "assistant", content: "Done.", stop_reason: "stop" }

to_json¶

message.to_json  # => String

JSON representation.

Predicates¶

message.text?       # => true
message.tool_call?  # => false
message.assistant?  # => true (if role is "assistant")
message.user?       # => false
message.stopped?    # => true (if stop_reason is "stop")

Examples¶

System Message¶

message = TextMessage.new(role: "system", content: "You are a helpful assistant")
message.system?  # => true

User Message¶

message = TextMessage.new(role: "user", content: "What's the weather?")
message.user?  # => true

Assistant Response¶

message = TextMessage.new(
  role: "assistant",
  content: "Your order has shipped!",
  stop_reason: "stop"
)
message.assistant?  # => true
message.stopped?    # => true

In Robot Results¶

Robot#run returns a RobotResult, not a TextMessage. RobotResult has no text? and no content — calling either raises NoMethodError. Read the reply with last_text_content (aliased as reply):

result = robot.run("Tell me a joke")

puts result.last_text_content   # => the assistant's text
puts result.reply               # => same thing
result.stopped?                 # => true whenever there are no tool calls
result.has_tool_calls?          # => whether the final message carried tool calls

RobotResult#stopped? is not driven by stop_reason

A RobotResult produced by Robot#run always has stop_reason == nil (RubyLLM::Message does not define the method, so build_result falls back to nil), and the TextMessage it wraps is built without a stop_reason too. stopped? therefore reduces to !has_tool_calls? — it never becomes true because a stop_reason of "stop" was reported. The stop_reason: "stop" form shown above only applies to TextMessage instances you construct yourself.

result.output is an Array holding a single TextMessage rebuilt from the final response text — it is not the full turn:

msg = result.output.first
msg.text?      # => true
msg.content    # => the assistant's text

Filtering Text Content¶

# Get only text messages from memory
text_messages = memory.messages.select(&:text?).map(&:content)