Crate leviath_core 

Leviath Core

Core types and traits for the Leviath agent framework.

This crate provides the foundational types for building agents with structured, hardware-inspired context window management. It includes:

• Regions: Typed memory regions with different lifecycle policies
• Layouts: Complete memory maps defining how context is structured
• Blueprints: Agent definitions including stages, models, and tools
• Lifecycle: Policies for eviction, compaction, and context management

Re-exports

pub use blueprint::Blueprint;

pub use blueprint::ContextTransform;

pub use blueprint::EdgeTransform;

pub use blueprint::FileTrackingConfig;

pub use blueprint::NudgeConfig;

pub use blueprint::ReadPathsConfig;

pub use blueprint::RepetitionDetectionConfig;

pub use blueprint::ResolvedNudge;

pub use blueprint::Stage;

pub use blueprint::StuckConfig;

pub use blueprint::ToolResultRouting;

pub use blueprint::TransitionCondition;

pub use blueprint::TransitionEdge;

pub use blueprint::resolve_nudge;

pub use cache::CacheHint;

pub use context_cause::ContextCause;

pub use credentials::CredentialStore;

pub use credentials::CredentialStoreKind;

pub use credentials::MemoryStore;

pub use credentials::mcp_account;

pub use credentials::provider_account;

pub use error::Error;

pub use error::Result;

pub use error::ValidationError;

pub use layout::BudgetSpec;

pub use layout::ContextLayout;

pub use layout::RegionDefinition;

pub use lifecycle::CompactionConfig;

pub use output::FINAL_OUTPUT_FILE;

pub use output::FinalOutput;

pub use output::FinalOutputDescriptor;

pub use output::MAX_FINAL_OUTPUT_BYTES;

pub use output::OutputSpec;

pub use output::describe_spec;

pub use output::resolve_output_spec;

pub use panic_payload::panic_message;

pub use paths::agents_dir;

pub use paths::canonicalize_for_match;

pub use paths::data_dir;

pub use paths::home_dir;

pub use paths::is_safe_path_component;

pub use paths::providers_dir;

pub use paths::resolves_within;

pub use paths::tools_dir;

pub use policy::AllowlistRule;

pub use policy::McpToolOverride;

pub use policy::PolicyConfig;

pub use read_paths::ReadPathDecision;

pub use read_paths::ReadPathEntry;

pub use read_paths::ReadPathPolicy;

pub use read_paths::ReadPathSet;

pub use read_paths::validate_entry_syntax;

pub use region::ContentFormat;

pub use region::EntryKind;

pub use region::EvictionStrategy;

pub use region::Region;

pub use region::RegionEntry;

pub use region::RegionKind;

pub use region::RegionSchema;

pub use region::SerializedToolCall;

pub use region::Volatility;

pub use sandbox::OnUnavailable;

pub use sandbox::SandboxKind;

pub use sandbox::ToolSandboxConfig;

pub use sandbox::resolve_sandbox;

pub use secrets::ShellEnvMode;

pub use secrets::child_env_allowed;

pub use secrets::constant_time_eq;

pub use secrets::dotenv_var_allowed;

pub use secrets::is_secret_header;

pub use secrets::is_sensitive_env_name;

pub use secrets::redact;

pub use secrets::script_env_allowed;

pub use secrets::withheld_child_vars;

pub use taint::GateDecision;

pub use taint::GateDecisionSource;

pub use taint::GateEvent;

pub use taint::RegionTaint;

pub use taint::SecurityConfig;

pub use taint::TaintLevel;

pub use taint::ToolClassification;

pub use taint::ToolDirection;

pub use text::estimate_tokens;

pub use text::floor_char_boundary;

pub use text::truncate_at_boundary;

pub use text::truncate_chars;

Modules

blueprint

Agent blueprints and stage definitions.

cache

Cache hint types for prompt caching across providers.

config

Plain configuration value types shared across crates.

context_cause

Why a context window changed.

credentials

Where Leviath’s long-lived secrets live.

duration

How Leviath writes a span of seconds, in the two shapes its surfaces need.

error

Error types for Leviath Core.

execution

Execution identity: what a run did, told apart from what it was asked to do.

files

The names of the files a run directory and an agent directory hold.

interaction

Plain value types for the worker ↔ dashboard interaction channel.

layout

Context window layouts and memory maps.

lifecycle

LLM compaction configuration for regions that summarize on overflow.

manifest

Manifest parsing for agent.leviath files.

mcp_names

The one place that decides what an MCP tool is called.

mime

Typed content: mime types, parts, and where their bytes live.

output

An agent’s final output: the one value a run hands back to whoever asked.

panic_payload

Rendering a caught panic payload as a human-readable message.

paths

Path containment, and the one definition of where Leviath’s data lives.

policy

Policy rules for taint tracking allowlists.

read_paths

The [read_paths] allowlist: how an agent is granted read access outside its workdir, and how each access is checked.

region

Memory region types and validation schemas.

run_archive

A portable, self-contained record of an entire agent run.

run_meta

Plain, serializable run-state data types.

sandbox

Sandboxed tool-execution configuration.

secrets

Which environment variables agent-supplied code may see.

sync

Taking a lock without a panic path.

taint

Context taint tracking types for security gating.

telemetry

The telemetry seam: pure-data lifecycle events and the sink they flow into.

text

Cutting a &str at a byte offset without splitting a character.

write_limits

Deciding whether an agent may write, and how much.

Functions

default_true

Serde default for a flag that is on unless a file turns it off.