API reference

The full public API exported from langstitch. Import anything from the top level:

from langstitch import (
    graph_node, graph, skill,
    input_guardrail, output_guardrail,
    business_policy, persona, configuration,
    langstitch_graph_server, GraphBuilder, LangStitchApp,
    load_config, get_registry, START, END,
)

Decorators

Symbol	Kind	Purpose
@graph_node	decorator	node handler state → dict
@graph	decorator	graph builder (entrypoint=, parent=)
@skill	decorator	reusable capability
@input_guardrail / @output_guardrail	decorator	inbound/outbound validation
@business_policy	decorator	priority-ordered org rule
@persona	decorator	identity / system prompt
@configuration	decorator	bind a config section to a dataclass
@tool / @worker_agent	decorator	LLM tool / delegatable sub-agent
@langstitch_graph_server	decorator	graph API server (protocol, port, name, properties)

MCP

Symbol	Kind	Purpose
@langstitch_mcp_server	decorator	MCP server class + transport
@mcp_tool	decorator	expose a callable as an MCP tool
@mcp_resource	decorator	expose a readable MCP resource
@mcp_prompt	decorator	expose a reusable MCP prompt

Graph

Symbol	Kind	Purpose
GraphBuilder	class	declarative wiring → LangGraph
START, END	const	edge sentinels

Runtime

Symbol	Kind	Purpose
LangStitchApp	class	runtime: bootstrap(), build_graph(), invoke(), info()
create_app	fn	build the FastAPI app (needs server)
run	fn	start the server

Providers & helpers

Symbol	Kind	Purpose
get_config, reset_config_cache	fn	cached config access
get_env, get_secret	fn	environment & secret access
get_logger	fn	configured logger
get_llm_provider	fn	chat model from model: config
get_http_client, get_async_http_client	fn	configured httpx clients

External services

Symbol	Kind	Purpose
AuthConfig, ServiceConfig	dataclass	service definitions
ServiceClient, AsyncServiceClient	class	typed HTTP clients
load_service_config, format_path	fn	service helpers
set_request_headers, get_request_headers, clear_request_headers	fn	header propagation

Config

Symbol	Kind	Purpose
AppConfig	class	parsed configuration object
load_config, load_application_config, load_env	fn	load config & env
find_project_root	fn	locate the project root
query_json	fn	JSON-path lookups
compile_config	fn	YAML → JSON precompile

Registry

Symbol	Kind	Purpose
Registry, get_registry, reset_registry	class/fn	the process-global registry

Dynamic registries

Symbol	Kind	Purpose
ToolRegistry, AgentRegistry	class	lazy spec registries
get_tool_registry, get_agent_registry	fn	registry accessors
get_all_tools, get_all_worker_agents	fn	list specs
get_input_guardrails, get_output_guardrails	fn	list guardrail specs
get_skills, get_policies, get_personas	fn	list specs
refresh_registries	fn	force a refresh

Hierarchical context

Symbol	Kind	Purpose
Context, ContextScope, ContextBuilder	class	context primitives
LLMContext	class	the object a model callback receives
run_llm, run_worker_agent	fn	run an isolated LLM / sub-agent call

Source of truth

Exhaustive signatures and options ship with the langstitch-sdk package on PyPI — inspect them via python -c "help('langstitch')" after install.