2.4 compatibility in Nexa 3.0

This API serves the 2.4 compatibility path. Open Programs use explicit capabilities and controller-owned adapters.

Standard library API

This reference is generated from Nexa 3.0's retained 2.4 tool registry. Names below are exact registry identifiers. Expose a namespace with uses std.fs, or call supported DSL wrappers such as std.fs.read(path). Required and optional parameters describe the JSON tool interface. Return types are the registered handler's annotations; unspecified means no annotation is declared. See the full schema snapshot for property descriptions.

Execution and errors

Agent-dispatched tools check exposure and approval before execution. Direct standard-library calls run as trusted program code. Filesystem mutation is disabled by default in the legacy standard-library layer; its NEXA_ENABLE_DANGEROUS_TOOLS and NEXA_ALLOWED_WRITE_ROOTS configuration is separate from Agent approval. Configure only reviewed, task-specific permissions. Regular handler failures may return an Error: string; uncertain transport failures propagate to preserve unknown-outcome recovery. Database handles and several collection results are JSON strings; explicitly decode them when local structured values are required. PostgreSQL and external services require their application dependencies. std.ui needs the terminal extra.

std.fs

Registry name	Required parameters	Optional parameters	Return annotation
file_read	path: string	encoding: string	str
file_write	path: string, content: string	—	str
file_exists	path: string	—	str
file_list	directory: string	pattern: string	str
file_append	path: string, content: string	—	str
file_delete	path: string	—	str
file_edit	path: string, old_text: string, new_text: string	—	str

std.http

Registry name	Required parameters	Optional parameters	Return annotation
http_get	url: string	headers: object, timeout: integer	str
http_post	url: string, data: string	headers: object, content_type: string	str
http_put	url: string, data: string	headers: object	str
http_delete	url: string	headers: object	str

std.time

Registry name	Required parameters	Optional parameters	Return annotation
time_now	—	format: string	str
time_diff	start: string, end: string	unit: string	str
time_format	iso_string: string	format: string	str
time_sleep	seconds: integer	—	str
time_timestamp	—	—	str

std.text

Registry name	Required parameters	Optional parameters	Return annotation
text_split	text: string	delimiter: string	str
text_replace	text: string, old: string, new: string	—	str

std.json

Registry name	Required parameters	Optional parameters	Return annotation
json_parse	text: string	—	str
json_get	text: string, path: string	—	str
json_stringify	data: string	indent: integer	str

std.hash

Registry name	Required parameters	Optional parameters	Return annotation
hash_md5	text: string	—	str
hash_sha256	text: string	—	str
base64_encode	text: string	—	str
base64_decode	text: string	—	str

std.math

Registry name	Required parameters	Optional parameters	Return annotation
math_calc	expression: string	—	str
math_random	min_val: integer, max_val: integer	—	str

std.regex

Registry name	Required parameters	Optional parameters	Return annotation
regex_match	pattern: string, text: string	flags: string	str
regex_replace	pattern: string, replacement: string, text: string	—	str

std.shell

Registry name	Required parameters	Optional parameters	Return annotation
shell_exec	command: string	timeout: integer	str
shell_which	command: string	—	str

std.code

Registry name	Required parameters	Optional parameters	Return annotation
search_files	pattern: string	directory: string	str
list_directory	directory: string	—	str
file_edit	path: string, old_text: string, new_text: string	—	str

std.ask_human

Registry name	Required parameters	Optional parameters	Return annotation
ask_human	prompt: string	default: string	str

std.db.sqlite

Registry name	Required parameters	Optional parameters	Return annotation
std_db_sqlite_connect	path: string	—	str
std_db_sqlite_query	handle_json: string, sql: string	params_json: string	str
std_db_sqlite_query_one	handle_json: string, sql: string	params_json: string	str
std_db_sqlite_execute	handle_json: string, sql: string	params_json: string	str
std_db_sqlite_close	handle_json: string	—	str
std_db_sqlite_begin	handle_json: string	—	str
std_db_sqlite_commit	handle_json: string	—	str
std_db_sqlite_rollback	handle_json: string	—	str

std.db.postgres

Registry name	Required parameters	Optional parameters	Return annotation
std_db_postgres_connect	url: string	—	str
std_db_postgres_query	handle_json: string, sql: string	params_json: string	str
std_db_postgres_query_one	handle_json: string, sql: string	params_json: string	str
std_db_postgres_execute	handle_json: string, sql: string	params_json: string	str
std_db_postgres_close	handle_json: string	—	str
std_db_postgres_begin	handle_json: string	—	str
std_db_postgres_commit	handle_json: string	—	str
std_db_postgres_rollback	handle_json: string	—	str

std.db.memory

Registry name	Required parameters	Optional parameters	Return annotation
std_db_memory_query	handle_json: string, agent_name: string, key: string	—	str
std_db_memory_store	handle_json: string, agent_name: string, key: string, value: string	—	str
std_db_memory_delete	handle_json: string, agent_name: string, key: string	—	str
std_db_memory_list	handle_json: string, agent_name: string	—	str

std.auth

Registry name	Required parameters	Optional parameters	Return annotation
std_auth_oauth	name: string, client_id: string, client_secret: string	opts: string	unspecified
std_auth_enable_auth	providers: string	options: string	unspecified
std_auth_get_user	request: string	—	unspecified
std_auth_get_session	request: string	—	unspecified
std_auth_session_data	request: string	—	unspecified
std_auth_set_session	request: string, data: string	—	unspecified
std_auth_logout_user	request: string	—	unspecified
std_auth_require_auth	request: string	—	unspecified
std_auth_jwt_sign	claims: string, secret: string	options: string	unspecified
std_auth_jwt_verify	token: string, secret: string	—	unspecified
std_auth_jwt_decode	token: string	—	unspecified
std_auth_csrf_token	request: string	—	unspecified
std_auth_csrf_field	request: string	—	unspecified
std_auth_verify_csrf	request: string, token: string	—	unspecified
std_auth_api_key_generate	agent_name: string	ttl: string	unspecified
std_auth_api_key_verify	api_key: string	—	unspecified
std_auth_auth_context	request: string	agent: string	unspecified

std.kv

Registry name	Required parameters	Optional parameters	Return annotation
std_kv_open	path: string	—	unspecified
std_kv_get	kv: string, key: string	default: string	unspecified
std_kv_get_int	kv: string, key: string	default: string	unspecified
std_kv_get_str	kv: string, key: string	default: string	unspecified
std_kv_get_json	kv: string, key: string	—	unspecified
std_kv_set	kv: string, key: string, value: string	opts: string	unspecified
std_kv_set_nx	kv: string, key: string, value: string	opts: string	unspecified
std_kv_del	kv: string, key: string	—	unspecified
std_kv_has	kv: string, key: string	—	unspecified
std_kv_list	kv: string	prefix: string	unspecified
std_kv_expire	kv: string, key: string, ttl_seconds: string	—	unspecified
std_kv_ttl	kv: string, key: string	—	unspecified
std_kv_flush	kv: string	—	unspecified
std_kv_incr	kv: string, key: string	amount: string	unspecified
std_kv_agent_kv_query	kv: string, semantic_query: string	—	unspecified
std_kv_agent_kv_store	kv: string, key: string, value: string	context: string	unspecified
std_kv_agent_kv_context	kv: string, agent: string	—	unspecified

std.concurrent

Registry name	Required parameters	Optional parameters	Return annotation
std_concurrent_channel	—	—	unspecified
std_concurrent_send	tx: string, value: string	—	unspecified
std_concurrent_recv	rx: string	—	unspecified
std_concurrent_recv_timeout	rx: string, ms: string	—	unspecified
std_concurrent_try_recv	rx: string	—	unspecified
std_concurrent_close	rx: string	—	unspecified
std_concurrent_select	channels: string	timeout_ms: string	unspecified
std_concurrent_spawn	handler: string	—	unspecified
std_concurrent_await_task	task: string	—	unspecified
std_concurrent_try_await	task: string	—	unspecified
std_concurrent_cancel_task	task: string	—	unspecified
std_concurrent_parallel	handlers: string	—	unspecified
std_concurrent_race	handlers: string	—	unspecified
std_concurrent_after	delay: string, handler: string	—	unspecified
std_concurrent_schedule	interval: string, handler: string	—	unspecified
std_concurrent_cancel_schedule	schedule: string	—	unspecified
std_concurrent_sleep_ms	ms: string	—	unspecified
std_concurrent_thread_count	—	—	unspecified

std.template

Registry name	Required parameters	Optional parameters	Return annotation
std_template_render	template_str: string	data: string	unspecified
std_template_template	path: string	data: string	unspecified
std_template_compile	path: string	—	unspecified
std_template_render_compiled	compiled: string	data: string	unspecified
std_template_filter_apply	value: string, filter_name: string	filter_args: string	unspecified
std_template_agent_prompt	agent: string, template_str: string	context: string	unspecified
std_template_agent_slot_fill	agent: string, template_str: string	slot_sources: string	unspecified
std_template_agent_register	agent: string, name: string, template_str: string	—	unspecified
std_template_agent_list	—	—	unspecified
std_template_filter_upper	value: string	—	unspecified
std_template_filter_lower	value: string	—	unspecified
std_template_filter_capitalize	value: string	—	unspecified
std_template_filter_trim	value: string	—	unspecified
std_template_filter_default	value: string	default: string	unspecified
std_template_filter_length	value: string	—	unspecified
std_template_filter_json	value: string	—	unspecified
std_template_filter_escape	value: string	—	unspecified
std_template_filter_url_encode	value: string	—	unspecified

std.pipe

Registry name	Required parameters	Optional parameters	Return annotation
std_pipe_apply	value: string, func: string	extra_args: string	unspecified

std.defer

Registry name	Required parameters	Optional parameters	Return annotation
std_defer_schedule	expression: string	—	unspecified

std.null_coalesce

Registry name	Required parameters	Optional parameters	Return annotation
std_null_coalesce_apply	value: string, fallback: string	—	unspecified

std.string

Registry name	Required parameters	Optional parameters	Return annotation
std_string_interpolate	template: string	context: string	unspecified

std.match

Registry name	Required parameters	Optional parameters	Return annotation
std_match_pattern	value: string, pattern: string	—	unspecified
std_match_destructure	value: string, pattern: string	—	unspecified
std_match_variant	enum: string, variant: string	fields: string	unspecified

std.ui

Registry name	Required parameters	Optional parameters	Return annotation
std_ui_banner	title: string	subtitle: string	str
std_ui_markdown	text: string	—	str
std_ui_code	code: string	language: string	str
std_ui_panel	text: string	title: string, style: string	str
std_ui_thinking	—	message: string, duration: number	str
std_ui_success	msg: string	—	str
std_ui_error	msg: string	—	str
std_ui_warning	msg: string	—	str
std_ui_info	msg: string	—	str
std_ui_input	—	prompt: string	str
std_ui_agent_reply	agent_name: string, reply: string	—	str
std_ui_tool_call	tool_name: string	args: string	str

std.struct

Registry name	Required parameters	Optional parameters	Return annotation
std_adt_register_struct	name: string, fields: string	—	unspecified
std_adt_make_struct	name: string	fields: string	unspecified
std_adt_lookup	kind: string, name: string	—	unspecified

std.enum

Registry name	Required parameters	Optional parameters	Return annotation
std_adt_register_enum	name: string, variants: string	—	unspecified
std_adt_make_variant	enum: string, variant: string	fields: string	unspecified
std_adt_lookup	kind: string, name: string	—	unspecified

std.trait

Registry name	Required parameters	Optional parameters	Return annotation
std_adt_register_trait	name: string, methods: string	—	unspecified
std_adt_register_impl	trait: string, type: string	methods: string	unspecified
std_adt_lookup	kind: string, name: string	—	unspecified
std_adt_summary	—	—	unspecified
std_adt_reset	—	—	unspecified

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Source and validation · stdlib / tools