Struct LlmTransition 

pub struct LlmTransition { /* private fields */ }

Wraps an LLM API call as a Ranvier Transition.

Builder API

LlmTransition::new(LlmProvider::Claude)
    .model("claude-sonnet-4-5-20250929")
    .system_prompt("You are a helpful assistant.")
    .prompt_template("Classify: {{content}}")
    .output_schema::<ModerationResult>()
    .max_tokens(200)
    .temperature(0.3)
    .retry_count(2)
    .with_label("ContentModeration")

Template Syntax

• {{variable}} — substituted with the String value of variable from the Bus (via bus.read::<LlmTemplateVars>()).
• {{json:variable}} — substituted with the JSON-serialized representation of variable from the Bus template vars.

Transition Contract

• Input (String): an optional runtime prompt override; when empty the stored prompt_template is used.
• Output (String): the raw LLM response text.
• Error (LlmError): typed fault for template, network, or validation failures.

Implementations

impl LlmTransition

pub fn new(provider: LlmProvider) -> Self

Create a new LlmTransition targeting provider.

pub fn model(self, model: impl Into<String>) -> Self

Set the model identifier (e.g. "claude-sonnet-4-5-20250929", "gpt-4o").

pub fn system_prompt(self, system: impl Into<String>) -> Self

Set an optional system prompt prepended to the conversation.

pub fn prompt_template(self, template: impl Into<String>) -> Self

Set the prompt template.

Template variables use {{variable}} for string substitution and {{json:variable}} for JSON-serialized substitution from the Bus.

pub fn max_tokens(self, max: u32) -> Self

Set the maximum number of tokens to generate.

pub fn temperature(self, temp: f32) -> Self

Set the sampling temperature (0.0 = deterministic, 1.0+ = creative).

pub fn retry_count(self, count: u32) -> Self

Set the number of automatic retries on transient failure (default 0).

pub fn with_label(self, label: impl Into<String>) -> Self

Override the transition label shown in the Schematic.

pub fn output_schema<T: Serialize + for<'de> Deserialize<'de> + Default>( self, ) -> Self

Store a JSON Schema derived from T for response validation.

When set, the LLM response will be parsed as JSON and validated against this schema. If validation fails the transition returns Outcome::Fault with LlmError::SchemaValidation.

The schema is generated from the serde_json representation of T. For richer schema generation, enable the schema feature and use schemars.

pub fn output_schema_raw(self, schema: Value) -> Self

Set a raw JSON Schema value directly for response validation.

Trait Implementations

impl Clone for LlmTransition

fn clone(&self) -> LlmTransition

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for LlmTransition

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Transition<String, String> for LlmTransition

type Error = LlmError

Domain-specific error type (e.g., AuthError, ValidationError)

type Resources = ()

The type of resources required by this transition. This follows the “Hard-Wired Types” principle from the Master Plan.

fn label(&self) -> String

Execute the transition.

fn description(&self) -> Option<String>

Returns a detailed description of what this transition does.

fn run<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, input: String, _resources: &'life1 Self::Resources, bus: &'life2 mut Bus, ) -> Pin<Box<dyn Future<Output = Outcome<String, Self::Error>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Execute the transition.

fn position(&self) -> Option<(f32, f32)>

Returns the visual position of this transition in a schematic. (x, y) coordinates.

fn bus_access_policy(&self) -> Option<BusAccessPolicy>

Optional transition-scoped Bus access policy (M143).

fn input_schema(&self) -> Option<Value>

Optional JSON Schema for the input type of this transition.