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Documentation Index

Fetch the complete documentation index at: https://docs.pflow.run/llms.txt

Use this file to discover all available pages before exploring further.

Agent commands. Your AI agent uses this node in workflows. You don’t configure it directly.
The LLM node calls AI models using LiteLLM. Use it when a step needs reasoning — summarization, classification, extraction, anything a Python expression can’t handle. It supports many providers (OpenAI, Anthropic, Google, OpenRouter, Ollama, and 100+ more) through a unified interface.

Parameters

ParameterTypeRequiredDefaultDescription
promptstrYes-Text prompt, or path to an external file (e.g., ./prompts/system.md)
modelstrNoSee belowModel identifier
systemstrNo-System prompt for behavior guidance
temperaturefloatNo1.0Sampling temperature (0.0-2.0)
max_tokensintNo-Maximum response tokens
imageslistNo[]Image URLs or file paths for vision models
output_schemadictNo-JSON Schema for structured output
prompt_cachelistNo[]Names of ## Cache chunks to include as a cached system prefix. See Prompt caching
prewarmboolNofalseOn batch nodes: run the first item synchronously to populate the provider cache, then fan out the rest as cache reads

Model resolution

If model is not specified in workflow params, pflow auto-detects based on your configured API keys. Most users just need an API key:
pflow settings set-env OPENAI_API_KEY "sk-..."
See LLM model settings for the full resolution order and default models per provider.

Output

KeyTypeDescription
responsestr or dictText response (str), or parsed JSON (dict) when output_schema is set
llm_usagedictToken usage metrics
errorstrError message (only present on failure)

Token usage structure

{
  "model": "openai/gpt-5.2",
  "input_tokens": 150,
  "uncached_input_tokens": 150,
  "output_tokens": 89,
  "total_tokens": 239,
  "cache_creation_input_tokens": 0,
  "cache_read_input_tokens": 0,
  "input_token_accounting": "total_includes_cache"
}

Model support

These providers are included with pflow - just set your API key: Always include the provider prefix in the model: field — bare names route inconsistently (Gemini bare names try Vertex; OpenAI bare names usually work but aren’t future-proof).
ProviderExample models
OpenAIopenai/gpt-5.2, openai/gpt-5.1, openai/gpt-4o
Anthropicanthropic/claude-opus-4-5, anthropic/claude-sonnet-4-5, anthropic/claude-haiku-4-5
Googlegemini/gemini-3.0-pro, gemini/gemini-2.5-flash
# Set API keys (stored in ~/.pflow/settings.json)
pflow settings set-env OPENAI_API_KEY "sk-..."
pflow settings set-env ANTHROPIC_API_KEY "sk-ant-..."
pflow settings set-env GEMINI_API_KEY "..."

Other providers

LiteLLM is built into pflow and recognizes 100+ providers natively — no plugin install needed. Set the appropriate API key (or omit it for Ollama) and reference the model with its provider prefix.

OpenRouter

pflow settings set-env OPENROUTER_API_KEY "sk-or-..."
### summarize

Summarize content using OpenRouter.

- type: llm
- model: openrouter/anthropic/claude-sonnet-4-5
- prompt: Summarize this

Ollama (local models)

brew install ollama
ollama serve
ollama pull llama3.2
### summarize

Summarize content using a local model.

- type: llm
- model: ollama/llama3.2
- prompt: Summarize this
See the LiteLLM provider list for the full set of supported providers (Mistral, Bedrock, Azure OpenAI, Vertex AI, vLLM, and more).

Image support

For vision-capable models, pass image URLs or local file paths:
### describe

Describe the contents of a photo.

- type: llm
- prompt: What's in this image?
- model: openai/gpt-5.2
- images: ["photo.jpg"]
Supported formats: JPEG, PNG, GIF, WebP, PDF Images can be:
  • Local file paths: photo.jpg, /path/to/image.png
  • URLs: https://example.com/image.jpg

Examples

Basic prompt

### summarize

Summarize the content from the previous step.

- type: llm
- prompt: Summarize: ${read.content}
- model: openai/gpt-4o-mini

With system prompt

### translate

Translate the input text to Spanish.

- type: llm
- system: You are a translator. Respond only with the translation.
- prompt: Translate to Spanish: ${input.text}
- temperature: 0.3

Structured output

Use output_schema to get guaranteed JSON matching a schema. The schema is passed to the model’s constrained decoding API — the model literally cannot produce non-conforming output.
### extract

Extract named entities from the document.

- type: llm
- prompt: Extract entities from: ${document.content}
- temperature: 0

```yaml output_schema
type: object
properties:
  people:
    type: array
    items:
      type: string
  places:
    type: array
    items:
      type: string
required:
  - people
  - places
```
When output_schema is set, response is a dict — downstream templates access fields directly: ${extract.response.people}. Without output_schema, you can still get JSON by prompting for it. The template system auto-parses JSON strings when you use dot notation: ${extract.response.people}. But the model may not always comply — output_schema is the reliable approach.

Image analysis

### analyze

Analyze the contents of a user-provided image.

- type: llm
- prompt: Describe the main elements in this image
- model: openai/gpt-5.2
- images: ["${file_path}"]

External prompt file

For long or reusable prompts, reference an external file instead of inlining. The file path is relative to the workflow file. Template variables (${var}) inside the file are resolved normally.
### analyze

Analyze source code for issues.

- type: llm
- prompt: ./prompts/code-review.md

Error handling

ErrorCauseSolution
Unknown modelModel ID not recognizedRun pflow settings llm show to see configured models, or check the LiteLLM provider list for supported model strings
API key requiredMissing credentialsSet with pflow settings set-env <PROVIDER>_API_KEY <value> or export <PROVIDER>_API_KEY=...
Rate limitToo many requestsWait and retry automatically (built-in retry)
The node retries transient failures automatically (3 attempts, 1 second wait).