Template Syntax

A template is the section of a prompt file following the Frontmatter.

---
# Frontmatter: YAML configuration
input:
  schema:
    param1: type, description
    param2?: type, optional description
---
Your templated prompt here with {{param1}} and {{param2}}.

Templates uses Handlebars syntax for dynamic content generation based on the input schema and available helpers.

Template Basics

Within a template you will primarily make use of the parameters defined in your input schema.

Variable Substitution

The simplest usage is direct variable substitution where you directly render the inputs:

---
input:
  schema:
    lang: string, Target language
    text: string, Text to translate
---
Translate the following text to {{lang}}:

{{text}}

Conditionals

You might also want to conditionally render parts of the template based a boolean input, or whether an optional parameter has been set:

---
input:
  schema:
    lang: string, Target language
    source-lang?: string, Source language, leave blank to auto detect
    text: string, Text to translate
    summarize?: boolean, Wheter to also summarize the text
---
{{#if source-lang}}
  Translate the given text from {{source-lang}} to {{lang}}
{{else}}
  Translate the given text to {{lang}}
{{/if}}

{{#if summarize}}
  Produce a summarized version of the translation.
{{/if}}

Here is the text:

{{text}}

Comments

Add comments that won't be included in the generated prompt:

{{!-- This is a comment --}}

Standard Input (stdin)

Standard Input is accessible via the stdin helper:

---
input:
  schema:
    lang: string, Target language
    text?: string, Text to translate, will default to stdin if not given
---
Translate the following text to {{lang}}:

{{#if text}}
  {{text}}
{{else}}
  {{stdin}}
{{/if}}

Helpers

Template helpers enable customizations in templates that go beyond basic variable substitution.

Basic Helpers

• {{#if words}}...{{/if}}: Conditional logic using Handlebars

Syntax	Description
{{{{raw}}}}..{{{{/raw}}}}	Print enclosed Handlebars expressions without rendering
{{#if ..}}..{{else}}..{{/if}}	Conditionally render blocks
{{#unless ..}}..{{else}}..{{/unless}}	Conditionally render blocks (if not)
{{eq a b}}	Check if a = b, renders to true or false
{{ne a b}}	Check if a != b, renders to true or false
{{gt a b}}	Check if a > b, renders to true or false
{{gte a b}}	Check if a >= b, renders to true or false
{{lt a b}}	Check if a < b, renders to true or false
{{lte a b}}	Check if a <= b, renders to true or false
{{and a b}}	Boolean "And", renders to true if both a and b are true
{{or a b}}	Boolean "Or", renders to true if either a or b is true
{{not a}}	Boolean "Not", renders to true or false, the inversion of a

You may use Boolean and Comparison expressions within conditional expressions:

simple

{{!-- if a > 1000 --}}
{{#if (gt a 1000)}}
...
{{/if}}

nested

{{!-- if a > 1000 && a < 2000  --}}
{{#if (and (gt a 1000) (lt a 2000))}}
...
{{/if}}

Remote-Capable Helpers

some helpers below are annotated with remote-capable. These are helpers whose behaviour change depending on whether the prompt is executing locally, or in a remote execution context such as SSH. The remote-context behaviour of each is described under each helper.

Non-remote capable helpers execute just fine in remote contexts, just without remote-dependant behaviour.

String Concatenation

Concatenate any number of strings together using the concat helper.

{{concat "string1" var1 "string2"}}

Exec Helper remote-capable

The exec helper enables execution of raw commands and inserting the output inline in your prompt. Both stdin and stderr are captured.

syntax

{{exec "command" "arg1" "arg2" "..."}}
{{exec "command" "arg1" var1 "..."}}
{{exec "command" "arg1" (concat var1 "value")}}

example

---
input:
  schema:
    repo: string, The github repository name
    branch?: string, Branch name, defaults to "main"
---
You are a github README assistant. Your task is to summarize a given README file,
indicating very briefly what the repo is about and installation instructions.

Here is the README:

{{#if branch}}
{{exec "curl" "-LsSf" (concat "https://raw.githubusercontent.com/" repo  "/refs/heads/" branch "/README.md")}}
{{ else }}
{{exec "curl" "-LsSf" (concat "https://raw.githubusercontent.com/" repo  "/refs/heads/main/README.md")}}
{{/if}}

INFO

When executed in a remote context, the command is executed on the remote host rather than on the local machine.

Prompt Helper

The prompt helper enables execution of other prompt files and inlining the output within the current prompt, in other words; nested prompting.

syntax

{{prompt "promptname" key1="value1" key2="value"}}
{{prompt "promptname" key1=var1 key2=var2}}

logs-aggregator.prompt

---
---

You will be given log summaries of several docker containers. Your task is to
summarize their findings in a short markdown report, grouped by container as a
section.

At the end of the report, make sure to highlight any problems, recommendations,
or actions to take.

## Postgres:
{{prompt "docker-inspect-logs" container="postgres"}}

## Nginx
{{prompt "docker-inspect-logs" container="nginx"}}

## Redis
{{prompt "docker-inspect-logs" container="redis"}}

docker-inspect-logs.prompt

---
input:
  schema:
    container: string, container name
---
Analyze the following logs and let me know if there are any problems:
{{exec "docker" "logs" container}}

Ask Helper

The Ask Helper enables interactively querying input from the user during execution time. In the following example, the URL used in curl is created from interactively querying the user for the repo name via (ask "Repo: " ), and branch name via (ask "Branch: " ).

syntax

{{ask "Question or Desc: "}}

example

---
---
You are a github README assistant. Your task is to summarize a given README file,
indicating very briefly what the repo is about and installation instructions.

Here is the README:

{{exec "curl" "-LsSf" (concat "https://raw.githubusercontent.com/" (ask "Repo: ")  "/refs/heads/" (ask "Branch: ") "/README.md")}}

Cat Helper remote-capable

Takes a file path and renders its contents inside the prompt.

syntax

{{cat "/path/to/file"}}

example

---
input:
  schema:
    path: string
---
You are a github README assistant. Your task is to summarize a given README file,
indicating very briefly what the repo is about and installation instructions.

Here is the README:

{{cat path}}

INFO

When executed in a remote context, the file path is read from remote instead of local machine.

Tail Helper remote-capable

Render the last n lines from a given file.

syntax

{{tail "/path/to/file" lines=5}}

example

---
input:
  schema:
    path: string
    lines: integer
---

{{tail path lines=lines}}

INFO

When executed in a remote context, the file path is read from remote instead of local machine.

Head Helper remote-capable

Render the first n lines from a given file.

syntax

{{head "/path/to/file" lines=5}}

example

---
input:
  schema:
    path: string
    lines: integer
---

{{head path lines=lines}}

INFO

When executed in a remote context, the file path is read from remote instead of local machine.

Env Helper remote-capable

Read environment variable

syntax

{{env name default}}

example

---
---

Shell Path: {{env "SHELL"}}
Shell Name: {{exec "basename" (env "SHELL")}}
Non-existent, with default: {{env "NON_EXISTENT" "Default Value"}}

INFO

When executed in a remote context, the environment is read from remote instead of local.