Struct AgentConfig 

pub struct AgentConfig {
    pub system_prompt: String,
    pub model: ModelSpec,
    pub tool_names: Vec<String>,
    pub retry: RetryConfig,
    pub stream_options: StreamOptionsConfig,
    pub steering_mode: SteeringModeConfig,
    pub follow_up_mode: FollowUpModeConfig,
    pub structured_output_max_retries: usize,
    pub approval_mode: ApprovalModeConfig,
    pub plan_mode_addendum: Option<String>,
    pub cache_config: Option<CacheConfigData>,
    pub extra: Value,
}

A fully serializable snapshot of agent configuration.

Captures the subset of AgentOptions fields that can survive a serde round-trip. Trait objects (tools, stream functions, transformers, policies, callbacks) cannot be serialized and must be re-registered by the consumer after deserialization.

What round-trips faithfully

system_prompt, model, retry, stream_options, steering_mode, follow_up_mode, structured_output_max_retries, approval_mode, plan_mode_addendum, and cache_config are all restored by into_agent_options().

What does NOT round-trip

• tool_names — stored for informational use only (e.g., re-registering tools by name). The consumer must supply the actual tool implementations.
• extra — application-level metadata that has no corresponding AgentOptions field. Survives serde but is not fed back into the agent.
• Trait objects — stream_fn, convert_to_llm, transform_context, approve_tool, policies, event forwarders, etc. must be re-attached.

Example

// Save
let config = agent.options().to_config();
let json = serde_json::to_string(&config)?;

// Restore
let config: AgentConfig = serde_json::from_str(&json)?;
let opts = AgentOptions::from_config(config, stream_fn, convert_to_llm)
    .with_tools(re_register_tools(&config.tool_names));

Fields

system_prompt: String

System prompt sent to the LLM.

model: ModelSpec

Model specification (provider, model ID, thinking level, etc.).

tool_names: Vec<String>

Names of registered tools (routing keys from AgentTool::name()).

retry: RetryConfig

Retry strategy parameters.

stream_options: StreamOptionsConfig

Per-call stream options (temperature, max tokens, transport).

steering_mode: SteeringModeConfig

Steering queue drain mode.

follow_up_mode: FollowUpModeConfig

Follow-up queue drain mode.

structured_output_max_retries: usize

Max retries for structured output validation.

approval_mode: ApprovalModeConfig

Approval mode for the tool gate.

plan_mode_addendum: Option<String>

Optional plan mode addendum appended to the system prompt.

cache_config: Option<CacheConfigData>

Optional context caching configuration.

extra: Value

Arbitrary extension data for application-specific config.

This field survives serialization but is not restored into AgentOptions — it has no corresponding field there. Use it to store application-level metadata alongside the config.

Implementations

impl AgentConfig

pub fn into_agent_options( self, stream_fn: Arc<dyn StreamFn>, convert_to_llm: impl Fn(&AgentMessage) -> Option<LlmMessage> + Send + Sync + 'static, ) -> AgentOptions

Restore an AgentOptions builder from this config.

The caller must supply the required non-serializable arguments (stream_fn and convert_to_llm) and then re-attach any trait objects (tools, transformers, policies) via the builder methods.

Trait Implementations

impl Clone for AgentConfig

fn clone(&self) -> AgentConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AgentConfig

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for AgentConfig

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for AgentConfig

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.