ollama/docs/modelfile.md

Ollama Model File

Note: this model file syntax is in development

A model file is the blueprint to create and share models with Ollama.

Table of Contents

• Format
• Examples
• Instructions
  • FROM (Required)
    • Build from llama2
    • Build from a bin file
  • PARAMETER
    • Valid Parameters and Values
  • TEMPLATE
    • Template Variables
  • SYSTEM
  • LICENSE
• Notes

Format

The format of the Modelfile:

# comment
INSTRUCTION arguments

Instruction	Description
FROM (required)	Defines the base model to use.
PARAMETER	Sets the parameters for how Ollama will run the model.
TEMPLATE	The full prompt template to be sent to the model.
SYSTEM	Specifies the system prompt that will be set in the template.
LICENSE	Specifies the legal license.

Examples

An example of a model file creating a mario blueprint:

FROM llama2
# sets the temperature to 1 [higher is more creative, lower is more coherent]
PARAMETER temperature 1
# sets the context window size to 4096, this controls how many tokens the LLM can use as context to generate the next token
PARAMETER num_ctx 4096

# sets a custom system prompt to specify the behavior of the chat assistant
SYSTEM You are Mario from super mario bros, acting as an assistant.

To use this:

1. Save it as a file (eg. Modelfile)
2. ollama create NAME -f <location of the file eg. ./Modelfile>'
3. ollama run NAME
4. Start using the model!

More examples are available in the examples directory.

Instructions

FROM (Required)

The FROM instruction defines the base model to use when creating a model.

FROM <model name>:<tag>

Build from llama2

FROM llama2

A list of available base models: https://github.com/jmorganca/ollama#model-library

Build from a bin file

FROM ./ollama-model.bin

This bin file location should be specified as an absolute path or relative to the Modelfile location.

PARAMETER

The PARAMETER instruction defines a parameter that can be set when the model is run.

PARAMETER <parameter> <parametervalue>

Valid Parameters and Values

Parameter	Description	Value Type	Example Usage
mirostat	Enable Mirostat sampling for controlling perplexity. (default: 0, 0 = disabled, 1 = Mirostat, 2 = Mirostat 2.0)	int	mirostat 0
mirostat_eta	Influences how quickly the algorithm responds to feedback from the generated text. A lower learning rate will result in slower adjustments, while a higher learning rate will make the algorithm more responsive. (Default: 0.1)	float	mirostat_eta 0.1
mirostat_tau	Controls the balance between coherence and diversity of the output. A lower value will result in more focused and coherent text. (Default: 5.0)	float	mirostat_tau 5.0
num_ctx	Sets the size of the context window used to generate the next token. (Default: 2048)	int	num_ctx 4096
num_gpu	The number of GPUs to use. On macOS it defaults to 1 to enable metal support, 0 to disable.	int	num_gpu 1
num_thread	Sets the number of threads to use during computation. By default, Ollama will detect this for optimal performance. It is recommended to set this value to the number of physical CPU cores your system has (as opposed to the logical number of cores).	int	num_thread 8
repeat_last_n	Sets how far back for the model to look back to prevent repetition. (Default: 64, 0 = disabled, -1 = num_ctx)	int	repeat_last_n 64
repeat_penalty	Sets how strongly to penalize repetitions. A higher value (e.g., 1.5) will penalize repetitions more strongly, while a lower value (e.g., 0.9) will be more lenient. (Default: 1.1)	float	repeat_penalty 1.1
temperature	The temperature of the model. Increasing the temperature will make the model answer more creatively. (Default: 0.8)	float	temperature 0.7
stop	Sets the stop tokens to use.	string	stop "AI assistant:"
tfs_z	Tail free sampling is used to reduce the impact of less probable tokens from the output. A higher value (e.g., 2.0) will reduce the impact more, while a value of 1.0 disables this setting. (default: 1)	float	tfs_z 1
top_k	Reduces the probability of generating nonsense. A higher value (e.g. 100) will give more diverse answers, while a lower value (e.g. 10) will be more conservative. (Default: 40)	int	top_k 40
top_p	Works together with top-k. A higher value (e.g., 0.95) will lead to more diverse text, while a lower value (e.g., 0.5) will generate more focused and conservative text. (Default: 0.9)	float	top_p 0.9

TEMPLATE

TEMPLATE of the full prompt template to be passed into the model. It may include (optionally) a system prompt and a user's prompt. This is used to create a full custom prompt, and syntax may be model specific.

Template Variables

Variable	Description
{{ .System }}	The system prompt used to specify custom behavior, this must also be set in the Modelfile as an instruction.
{{ .Prompt }}	The incoming prompt, this is not specified in the model file and will be set based on input.
{{ .First }}	A boolean value used to render specific template information for the first generation of a session.

TEMPLATE """
{{- if .First }}
### System:
{{ .System }}
{{- end }}

### User:
{{ .Prompt }}

### Response:
"""

SYSTEM """<system message>"""

SYSTEM

The SYSTEM instruction specifies the system prompt to be used in the template, if applicable.

SYSTEM """<system message>"""

LICENSE

The LICENSE instruction allows you to specify the legal license under which the model used with this Modelfile is shared or distributed.

LICENSE """
<license text>
"""

Notes

• the modelfile is not case sensitive. In the examples, we use uppercase for instructions to make it easier to distinguish it from arguments.
• Instructions can be in any order. In the examples, we start with FROM instruction to keep it easily readable.