Registry for tool functions with execution capabilities.
Acts as the single point of truth for tools available to an agent. Supports synchronous, asynchronous, and batched execution with configurable concurrency strategies (see ToolExecutionStrategy):
execute()— synchronous, blocking executionexecuteAsync()— asynchronous, non-blocking executionexecuteAll()— batch execution with a configurable ToolExecutionStrategy
Create a registry by passing an initial set of ToolFunction instances:
val registry = new ToolRegistry(Seq(myTool, anotherTool))
// or use the convenience factories:
ToolRegistry.empty
BuiltinTools.coreSafe.map(new ToolRegistry(_))
Value parameters
- initialTools
-
The tools available in this registry
Attributes
- Companion
- object
- Graph
-
- Supertypes
-
class Objecttrait Matchableclass Any
- Known subtypes
-
class MCPToolRegistry
Members list
Value members
Concrete methods
Executes a tool call synchronously, wrapping any thrown exception.
Executes a tool call synchronously, wrapping any thrown exception.
We use Try here (rather than org.llm4s.core.safety.Safety.safely) so that tool execution remains independent of the Safety API and returns Either for direct use by retry/timeout logic. Safety is still used elsewhere in the codebase (e.g. tracing, agent entry points).
Exceptions thrown inside the tool implementation are caught and converted to ToolCallError.ExecutionError with the original throwable preserved (so retry logic can treat e.g. IOException as retryable). Callers always receive a typed Either and never need to guard against unexpected exceptions from tool code.
Tool-returned Left values are propagated unchanged, so callers may receive any ToolCallError subtype that the tool itself produces (not only ExecutionError).
Value parameters
- request
-
The tool name and pre-parsed JSON arguments.
Attributes
- Returns
-
Right(result)on success;Left(ToolCallError.UnknownFunction)when no tool with the given name is registered;Left(ToolCallError.ExecutionError)when the tool throws an exception; orLeft(error)with the tool's ownToolCallErrorwhen the tool returns aLeftdirectly.
Executes a tool call with optional per-tool timeout and retry.
Executes a tool call with optional per-tool timeout and retry.
When config is default (no timeout, no retry), behavior is identical to execute.
Value parameters
- config
-
Optional timeout and retry policy
- ec
-
ExecutionContext required when timeout or retry is used
- request
-
The tool call request
Attributes
Execute multiple tool calls with a configurable strategy.
Execute multiple tool calls with a configurable strategy.
Value parameters
- ec
-
ExecutionContext for async execution
- requests
-
The tool call requests to execute
- strategy
-
Execution strategy (Sequential, Parallel, or ParallelWithLimit)
Attributes
- Returns
-
Future containing results in the same order as requests
Execute a tool call asynchronously.
Execute a tool call asynchronously.
Wraps synchronous execution in a Future for non-blocking operation. NOTE: Tool execution typically involves blocking I/O. We use blocking to hint the ExecutionContext to expand its pool if necessary.
Value parameters
- ec
-
ExecutionContext for async execution
- request
-
The tool call request
Attributes
- Returns
-
Future containing the result
Execute a tool call asynchronously with optional timeout and retry.
Execute a tool call asynchronously with optional timeout and retry.
Each attempt runs on a thread of ec and holds it for the attempt only. The backoff between two attempts holds no thread: it is a scheduled delay, after which the next attempt is dispatched to ec, so a small pool keeps serving other work while many calls wait to retry. (The synchronous execute still waits on its caller's thread, interruptibly, because a synchronous caller has nothing to resume.)
Value parameters
- config
-
Optional timeout and retry policy
- ec
-
ExecutionContext for async execution
- request
-
The tool call request
Attributes
Generate OpenAI tool definitions for all tools.
Generate OpenAI tool definitions for all tools.
Value parameters
- strict
-
When
true(default), all object properties are treated as required.
Attributes
- Returns
-
A
ujson.Arrcontaining one tool-definition object per registered tool
Get a specific tool by name
Get a specific tool by name
Attributes
All tools registered in this registry.
All tools registered in this registry.