Applies a chat template to a list of messages

Parameters:

• template: The template string (nil to use model's default)
• messages: Array of chat messages
• add_assistant: Whether to end with an assistant message prefix

Returns:

• The formatted prompt string

Raises:

• Llama::Error if template application fails

Gets the list of built-in chat templates

Returns:

• Array of template names

Generates text from a prompt using a model

This is a convenience method that loads a model, creates a context, and generates text in a single call.

response = Llama.generate(
  "/path/to/model.gguf",
  "Once upon a time",
  max_tokens: 100,
  temperature: 0.7
)
puts response

Parameters:

• model_path: Path to the model file (.gguf format)
• prompt: The input prompt
• max_tokens: Maximum number of tokens to generate (must be positive)
• temperature: Sampling temperature (0.0 = greedy, 1.0 = more random)

Returns:

• The generated text

Raises:

• ArgumentError if parameters are invalid
• Llama::Model::Error if model loading fails
• Llama::Context::Error if text generation fails

Thread-safe, idempotent initialization of the llama.cpp backend. You do not need to call this manually in most cases.

Get the current log level

Returns:

• The current log level

Set the log level

Parameters:

• level : Int32 - log level (0=DEBUG, 1=INFO, 2=WARNING, 3=ERROR, 4=NONE)

Example: Llama.log_level = Llama::LOG_LEVEL_ERROR # Only show errors Llama.log_level = Llama::LOG_LEVEL_NONE # Disable all logging

Set a custom log callback

The block receives:

• level : Int32 - log level (0=DEBUG, 1=INFO, 2=WARNING, 3=ERROR)
• message : String - log message

Example: Llama.log_set do |level, message| if level >= Llama::LOG_LEVEL_ERROR STDERR.print message end end

Measures elapsed time in milliseconds for a block using llama.cpp's clock.

elapsed = Llama.measure_ms do
  # ... code to measure ...
end
puts "Elapsed: #{elapsed} ms"

Returns:

• Float64: elapsed milliseconds

Process escape sequences in a string

This method processes common escape sequences like \n, \t, etc. in a string, converting them to their actual character representations.

text = Llama.process_escapes("Hello\\nWorld")
puts text # Prints "Hello" and "World" on separate lines

Parameters:

• text: The input string containing escape sequences

Returns:

• A new string with escape sequences processed

Returns the llama.cpp system information

This method provides information about the llama.cpp build, including BLAS configuration, CPU features, and GPU support.

info = Llama.system_info
puts info

Returns:

• A string containing system information

Returns the current time in milliseconds since the Unix epoch (llama.cpp compatible).

t0 = Llama.time_ms
# ... some processing ...
t1 = Llama.time_ms
elapsed = t1 - t0
puts "Elapsed: #{elapsed} ms"

Returns:

• Int64: milliseconds since epoch

Returns the current time in microseconds since the Unix epoch (llama.cpp compatible).

This is a high-level wrapper for LibLlama.llama_time_us.

t0 = Llama.time_us
# ... some processing ...
t1 = Llama.time_us
elapsed_ms = (t1 - t0) / 1000.0
puts "Elapsed: #{elapsed_ms} ms"

Returns:

• Int64: microseconds since epoch

Tokenize text and return formatted output

This is a convenience method that tokenizes text and returns a formatted string representation of the tokens.

model = Llama::Model.new("/path/to/model.gguf")
result = Llama.tokenize_and_format(model.vocab, "Hello, world!", ids_only: true)
puts result # Prints "[1, 2, 3, ...]"

Parameters:

• vocab: The vocabulary to use for tokenization
• text: The text to tokenize
• add_bos: Whether to add BOS token (default: true)
• parse_special: Whether to parse special tokens (default: true)
• ids_only: Whether to return only token IDs (default: false)

Returns:

• A formatted string representation of the tokens

Thread-safe, idempotent finalization of the llama.cpp backend. Call this if you want to explicitly release all backend resources before program exit.