> ## Documentation Index > Fetch the complete documentation index at: https://veryfront.com/docs/llms.txt > Use this file to discover all available pages before exploring further. # veryfront/tool > Define tools with schema-backed inputs for agents and MCP. ## Import ```ts theme={null} import { tool, dynamicTool, loadRemoteToolsFromSource, toolRegistry, createContext7ToolSource, createProjectScopedRemoteToolCatalog, } from "veryfront/tool"; ``` ## Examples ### Basic tool ```ts theme={null} import { tool } from "veryfront/tool"; import { defineSchema } from "veryfront/schemas"; const convertLength = tool({ id: "convert_length", description: "Convert meters to feet", inputSchema: defineSchema((v) => v.object({ meters: v.number().nonnegative().describe("Length in meters"), }) )(), execute: ({ meters }) => { return { feet: meters * 3.28084 }; }, }); ``` ### Use with an agent ```ts theme={null} import { agent } from "veryfront/agent"; import { tool } from "veryfront/tool"; import { defineSchema } from "veryfront/schemas"; const convertLength = tool({ id: "convert_length", description: "Convert meters to feet", inputSchema: defineSchema((v) => v.object({ meters: v.number().nonnegative().describe("Length in meters"), }) )(), execute: ({ meters }) => { return { feet: meters * 3.28084 }; }, }); const assistant = agent({ system: "You answer unit-conversion questions.", tools: { convert_length: convertLength }, maxSteps: 5, }); ``` ### Load remote tools for an agent ```ts theme={null} import { agent } from "veryfront/agent"; import { createRemoteMCPToolSource, loadRemoteToolsFromSource } from "veryfront/tool"; const docsTools = createRemoteMCPToolSource({ id: "docs-mcp", endpoint: "https://docs.example.com/mcp", headers: { Authorization: "Bearer " }, }); const runtimeTools = await loadRemoteToolsFromSource(docsTools, { context: { projectId: "proj_123" }, toolNameAliases: { search_docs: "docs_search" }, }); const assistant = agent({ system: "Use the docs tools when a question needs project documentation.", tools: runtimeTools, maxSteps: 5, }); const result = await assistant.generate({ input: "Find the deployment guide for this project.", }); ``` ## API ### `tool(config)` Create a typed tool definition. | Property | Type | Description | Source | | --------------------- | -------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------- | | `id?` | `string` | Tool identifier (optional, inferred from filename) | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L15) | | `description` | `string` | Tool description for the AI model | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L18) | | `inputSchema` | Schema\ \| JsonSchema | Input schema produced via `defineSchema((v) => …)` (or any `SchemaValidator`-backed builder), or a raw JSON Schema object for dynamic/project-authored tools. Schema validators parse before `execute`; raw JSON Schema is passed through to providers without runtime parsing. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L26) | | `outputSchema?` | Schema\ \| JsonSchema | Optional output schema. Hosts can use this to document or validate structured tool results. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L32) | | `allowUnknownSchema?` | `boolean` | Allow unknown/non-contract schemas to fall back to a permissive JSON schema. Use only for truly dynamic tools; prefer `v.unknown()` or `v.any()` from the SchemaValidator DSL instead. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L39) | | `execute` | (input: TInput, context?: ToolExecutionContext) => Promise\ \| TOutput | Tool execution function | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L44) | | `mcp?` | `object` | MCP configuration | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L47) | **Returns:** Tool\ ## Exports ### Components | Name | Description | Source | | -------------------------------- | ----------------------------------------- | ------------------------------------------------------------------------------------ | | `DEFAULT_SLEEP_TOOL_MAX_SECONDS` | Default value for sleep tool max seconds. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/sleep.ts#L7) | ### Functions | Name | Description | Source | | ------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------ | | `createContext7ToolSource` | Create context7 tool source. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/context7.ts#L26) | | `createProjectScopedRemoteToolCatalog` | Create project scoped remote tool catalog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L242) | | `createRemoteMCPToolSource` | Create remote MCP tool source. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/remote-mcp.ts#L414) | | `createSleepTool` | Create sleep tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/sleep.ts#L53) | | `createToolsFromHostDefinitions` | Create tools from host definitions. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/host-tools.ts#L80) | | `createToolsFromHostDefinitions` | Create tools from host definitions. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/host-tools.ts#L85) | | `createToolsFromHostDefinitions` | Create tools from host definitions. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/host-tools.ts#L90) | | `createToolsFromRemoteDefinitions` | Create tools from remote definitions. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/remote-source-tools.ts#L28) | | `dynamicTool` | Create a dynamic tool definition. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/factory.ts#L179) | | `executeTool` | Execute a tool definition with validated input. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/executor.ts#L15) | | `filterProjectScopedRemoteToolDefinitions` | Filter project scoped remote tool definitions. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L165) | | `hasToolExecutionErrorMarker` | Check whether tool execution error marker is present. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/result.ts#L6) | | `hydrateProjectScopedRemoteToolInput` | Input payload for hydrate project scoped remote tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L180) | | `isErroredToolExecutionResult` | Result returned from is errored tool execution. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/result.ts#L15) | | `isProjectNavigationRemoteTool` | Check whether a remote tool is project-navigation scoped. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L145) | | `isRemoteToolNameAllowed` | Check whether a remote tool name is allowed. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L157) | | `isToolVisibleTo` | Whether a registered tool is visible to the caller identified by the execution context. Unowned tools are project/global; owned tools are only visible to their owning agent. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/executor.ts#L10) | | `listProjectScopedRemoteToolNames` | List project scoped remote tool names. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L331) | | `loadRemoteToolsFromSource` | Loads remote tools from source. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/remote-source-tools.ts#L57) | | `resolveProjectScopedRemoteToolProjectId` | Resolves project scoped remote tool project ID. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L203) | | `tool` | Create a typed tool definition. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/factory.ts#L115) | | `traceHostTools` | Wrap host tools with tracing metadata. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/tracing.ts#L41) | ### Types | Name | Description | Source | | ----------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------- | | `Context7ToolSourceConfig` | Configuration used by context7 tool source. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/context7.ts#L6) | | `CreateSleepToolOptions` | Options accepted by create sleep tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/sleep.ts#L13) | | `DynamicToolConfig` | Configuration used by dynamic tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/factory.ts#L168) | | `HostToolDefinition` | Definition for host tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/host-tools.ts#L10) | | `HostToolMaterializationOptions` | Options accepted by host tool materialization. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/host-tools.ts#L33) | | `HostToolSet` | Public API contract for host tool set. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/host-tools.ts#L24) | | `HostToolTraceAttributeInput` | Input payload for host tool trace attribute. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/tracing.ts#L14) | | `HostToolTraceAttributes` | Public API contract for host tool trace attributes. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/tracing.ts#L11) | | `HostToolTraceRunner` | Public API contract for host tool trace runner. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/tracing.ts#L5) | | `JsonSchema` | Minimal JSON Schema type used by the `SchemaValidator` contract for `toJsonSchema()`. Kept in the extensions/schema category so the contract can reference it without depending on any non-leaf module. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/extensions/schema/json-schema.ts#L9) | | `ListProjectScopedRemoteToolNameOptions` | Options accepted by list project scoped remote tool name. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L62) | | `ProjectScopedRemoteToolCatalog` | Public API contract for project scoped remote tool catalog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L50) | | `ProjectScopedRemoteToolCatalogOptions` | Options accepted by project scoped remote tool catalog. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L16) | | `ProjectScopedRemoteToolDefaultProjectId` | Public API contract for project scoped remote tool default project ID. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L9) | | `ProjectScopedRemoteToolDefinitions` | Public API contract for project scoped remote tool definitions. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L30) | | `ProjectScopedRemoteToolExecution` | Public API contract for project scoped remote tool execution. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L43) | | `ProjectScopedRemoteToolExecutionInput` | Input payload for project scoped remote tool execution. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L36) | | `ProjectScopedRemoteToolOptions` | Options accepted by project scoped remote tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/project-scoped-remote-tools.ts#L4) | | `RemoteMCPToolSourceConfig` | Configuration used by remote MCP tool source. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/remote-mcp.ts#L9) | | `RemoteToolMaterializationOptions` | Options accepted by remote tool materialization. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/remote-source-tools.ts#L6) | | `RemoteToolSource` | Remote tool source loaded dynamically at runtime. Hosts can provide these to expose tools from remote MCP-compatible systems without registering those tools globally inside the framework. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L192) | | `SleepToolInput` | Input payload for sleep tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/sleep.ts#L44) | | `SleepToolOutput` | Output from sleep tool. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/sleep.ts#L47) | | `SleepToolWait` | Public API contract for sleep tool wait. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/sleep.ts#L10) | | `Tool` | Tool instance (returned by tool() function) | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L117) | | `ToolConfig` | Tool configuration options | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L13) | | `ToolDefinition` | Provider-facing tool definition used for model/tool registration. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L179) | | `ToolExecutionContext` | Context passed to tool execution | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L67) | | `ToolExecutionDataEvent` | Event emitted for tool execution data. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L97) | | `ToolSet` | Runtime tool map keyed by the tool name exposed to an agent. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/types.ts#L174) | | `TraceHostToolsOptions` | Options accepted by trace host tools. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/tracing.ts#L21) | ### Constants | Name | Description | Source | | -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------- | | `sleepTool` | Default sleep tool (max 60 s) exposed as a property accessor so the underlying `tool({...})` materialization is deferred until first use. Preserves the existing `sleepTool.execute(...)` call shape. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/sleep.ts#L91) | | `toolRegistry` | Shared tool registry value. | [source](https://github.com/veryfront/veryfront-code/blob/main/src/tool/registry.ts#L44) |