A single-file Python script for running .prompt files.

Quick start | Examples | Configuration | Providers

curl -O https://raw.githubusercontent.com/chr15m/runprompt/main/runprompt
chmod +x runprompt

Create hello.prompt:

---
model: anthropic/claude-sonnet-4-20250514
---
Say hello to {{name}}!

Run it:

export ANTHROPIC_API_KEY="your-key"
echo '{"name": "World"}' | ./runprompt hello.prompt

In addition to the following, see the tests folder for more example .prompt files.

---
model: anthropic/claude-sonnet-4-20250514
---
Summarize this text: {{STDIN}}

cat article.txt | ./runprompt summarize.prompt

The special {{STDIN}} variable always contains the raw stdin as a string.

Extract structured data using an output schema:

---
model: anthropic/claude-sonnet-4-20250514
input:
  schema:
    text: string
output:
  format: json
  schema:
    name?: string, the person's name
    age?: number, the person's age
    occupation?: string, the person's job
---
Extract info from: {{text}}

echo "John is a 30 year old teacher" | ./runprompt extract.prompt
# {"name": "John", "age": 30, "occupation": "teacher"}

Fields ending with ? are optional. The format is field: type, description.

Pipe structured output between prompts:

echo "John is 30" | ./runprompt extract.prompt | ./runprompt generate-bio.prompt

The JSON output from the first prompt becomes template variables in the second.

Override any frontmatter value from the command line:

./runprompt --model anthropic/claude-haiku-4-20250514 hello.prompt
./runprompt --name "Alice" hello.prompt

Set API keys for your providers:

export ANTHROPIC_API_KEY="..."
export OPENAI_API_KEY="..."
export GOOGLE_API_KEY="..."
export OPENROUTER_API_KEY="..."

Override any frontmatter value via environment variables prefixed with RUNPROMPT_:

export RUNPROMPT_MODEL="anthropic/claude-haiku-4-20250514"
./runprompt hello.prompt

This is useful for setting defaults across multiple prompt runs.

Use -v to see request/response details:

./runprompt -v hello.prompt

Models are specified as provider/model-name:

OpenRouter provides access to models from many providers (Anthropic, Google, Meta, etc.) through a single API key.