Prepare locally. Choose where to run.

Agent Tools: Tokens, MCP, Skills and Offline Evaluation

Use 18 browser-local tools for instructions, skills, context planning, MCP configuration, datasets and deterministic evaluation. Compare official external services by task and requirements.

browser tools
18
official resources
19

Choose the next step for your goal

01

Write the working rules

Use the instructions builder to define goals, boundaries and deliverables. Use the skill builder for repeatable steps. Add the resulting Markdown to the agent environment you actually use.

02

Align the interfaces

Prepare an MCP configuration and check its structure. Define data shapes with JSON Schema and substitute prompt variables. A valid format still needs compatibility checks in the target client.

03

Choose a runtime

Choose visual builders for node-based authoring, automation services for business app connections, or code frameworks for state and execution control. The cost tool estimates from prices you enter.

UTools

Local preparation tools

18

These browser tools generate, check or calculate text and configuration. They need no sign-in and make no model calls. Use them to prepare materials, then choose a runtime to execute agent tasks.

Local processing

Agent Instructions Builder

Turn your goal, project context and approval rules into an editable AGENTS.md or CLAUDE.md.

Open tool
Local processing

Agent Skill Builder

Create a SKILL.md with safely quoted YAML metadata and your own reusable workflow.

Open tool
Local processing

MCP Config Builder

Build client-specific MCP JSON for Claude Desktop, Cursor or VS Code without running commands.

Open tool
Local processing

MCP Config Validator

Check MCP JSON syntax and supported client semantics, with precise paths for issues.

Open tool
Local processing

Prompt Template Renderer

Fill explicit {{variables}} in prompts, including nested fields and JSON-array batches.

Open tool
Local processing

JSON Schema Builder

Infer a draft 2020-12 JSON Schema from sample JSON and validate another value locally.

Open tool
Local processing

Agent Cost Estimator

Estimate token charges from your own rates, tokens per step, step count and repeated runs.

Open tool
Local processing

Agent Task Planner

Arrange editable task dependencies and inspect a topological order and critical-path estimate.

Open tool
Local processing

Token Counter & Vocabulary Comparison

Count exact o200k_base or cl100k_base text tokens locally, inspect token IDs and compare both vocabularies.

Open tool
Local processing

Agent Context Budget Planner

Allocate a user-defined context window across editable text segments, output reserve and extra overhead.

Open tool
Local processing

RAG Text Splitter with Source Offsets

Prepare traceable text chunks with paragraph, line or fixed boundaries, a hard size cap and adjustable overlap.

Open tool
Local processing

MCP Config Converter

Convert MCP JSON between Claude Desktop, Cursor and VS Code with explicit checks for fields that cannot be preserved.

Open tool
Local processing

MCP Config Merger

Merge 2–10 MCP JSON files with server selection, custom names and explicit conflict strategies.

Open tool
Local processing

MCP Config Diff

Compare MCP servers and fields with stable Added, Removed, Changed and Unchanged results and private values masked by default.

Open tool
Local processing

Agent Output Evaluation Runner

Check existing model outputs with deterministic assertions, Unicode lengths and normalization settings.

Open tool
Local processing

Agent JSONL Dataset Validator

Check text conversations or input/output JSONL with physical line numbers and duplicate-ID detection.

Open tool
Local processing

Function Calling Tool Schema Builder

Wrap an inline JSON Schema for OpenAI Responses, Chat Completions or Anthropic tools.

Open tool
Local processing

Promptfoo Evaluation Config Builder

Prepare a literal YAML config with prompts, provider IDs, variables and deterministic assertions.

Open tool

External resource

Official external resources

19

These links open official websites or documentation in a new tab. UTools does not embed the services or collect their account details or API keys.

Showing 19 of 19 external resources

External resource

Visual builders

Dify

Connect model steps, knowledge retrieval and tools in a visual application workflow.

  • Hosted service
  • Self-hosted server
Requirements
Use a Dify Cloud account, or install its server with Docker Compose. Configure the model access and integration credentials your workflow needs.
Where it runs
Managed cloud or a server you operate; neither runs inside this directory.
Data boundary
Your deployment holds app data. Connected models, plugins and tracing services may receive inputs; self-hosting alone does not keep every request local.

Sources checked — Dify

External resource

Visual builders

Coze (global)

Build assistants with prompts, knowledge, tools and workflows on the international Coze platform.

  • Hosted service
Requirements
A Coze account is required. API integrations need access-token authentication and a published agent; service access depends on your account and region.
Where it runs
External hosted builder. This entry covers coze.com, separately from the China service.
Data boundary
Prompts and uploaded knowledge are processed by Coze and the services you connect. Review those services before adding private data.

Sources checked — Coze (global)

External resource

Agent workspaces

扣子 / Coze China

Use a Chinese-language Agent workspace for tasks, projects and collaboration, with skills, MCP and plugins.

  • Hosted service
Requirements
Register or sign in to a Coze China account. The web workspace needs no client installation; individual plugins can require extra connections or permissions.
Where it runs
Hosted workspace with separate desktop and mobile clients; not a browser-local utility.
Data boundary
Projects, conversations and files sync through the account. Connected plugins and MCP services add their own data access boundaries.

Sources checked — 扣子 / Coze China

External resource

Workflow automation

n8n

Connect triggers, business apps and AI steps into repeatable workflows.

  • Hosted service
  • Self-hosted server
Requirements
Use an n8n Cloud account or install and maintain a server. App connections require their own credentials; AI model nodes need suitable model access.
Where it runs
Managed cloud or self-hosted service. License and edition terms apply to your use case.
Data boundary
Workflows can move data between connected apps. Hosting controls where n8n runs; each destination still receives the data sent to it.

Sources checked — n8n

External resource

Visual builders

Flowise

Prototype agents and LLM flows with a visual node editor and reusable components.

  • Hosted service
  • Self-hosted server
Requirements
Use Flowise Cloud or install the Node.js/Docker server. Configure credentials for the model, vector store and tools you choose.
Where it runs
Cloud or a maintained backend; the editor is not an offline-only web tool.
Data boundary
The Flowise server and configured services process your flow data. Check storage, model and tool destinations before using confidential content.

Sources checked — Flowise

External resource

Visual builders

Langflow

Connect visual components into agent flows, then expose a flow through an API.

  • Self-hosted server
  • Install a runtime
Requirements
Install and start Langflow, configure server sign-in and your model credentials. API execution also uses a Langflow API key; the official tutorial uses OpenAI.
Where it runs
Run the Python service locally or deploy it on your infrastructure.
Data boundary
Your Langflow server stores flows; connected components can send data to model and third-party APIs. Server installation does not imply offline inference.

Sources checked — Langflow

External resource

Code frameworks

OpenAI Agents SDK

Write agents, function tools and handoffs in JavaScript or Python while controlling the application runtime.

  • Install a runtime
Requirements
Install the SDK in a development project. The official quickstart requires an OpenAI API key and API access; your application provides deployment and storage.
Where it runs
Application library, not a hosted visual builder. Install and run it in your own runtime.
Data boundary
The SDK runs in your app, while model requests go to the configured provider. The standard server-side path includes tracing; review tracing and data settings.

Sources checked — OpenAI Agents SDK

External resource

Code frameworks

Google Agent Development Kit

Build tool-using agents and agent teams in code, and test them with a local CLI or development web UI.

  • Install a runtime
Requirements
Install ADK in a supported language runtime. The Python quickstart uses a Gemini API key; other providers and cloud deployments have their own credentials.
Where it runs
Developer framework with local testing and separate deployment options.
Data boundary
The local development UI runs an agent runtime, not a local model by default. Data can go to the model, tools and deployment services you configure.

Sources checked — Google Agent Development Kit

External resource

Code frameworks

CrewAI

Coordinate role-based agents and use Flows to control state and execution order.

  • Install a runtime
Requirements
Install a Python environment and CrewAI CLI. Configure your LLM credentials; the official research tutorial also needs a Serper search API key.
Where it runs
This entry covers the installable framework; managed CrewAI offerings are separate.
Data boundary
Agents can send content to configured models, search and tool APIs. Review optional tracing and the services used by each task.

Sources checked — CrewAI

External resource

Code frameworks

LangGraph

Control stateful agent graphs with durable execution, streaming and human review points.

  • Install a runtime
Requirements
Install the framework and write your graph. A mock graph can run without a model key; real model calls need configured provider access. LangSmith is optional.
Where it runs
Installable orchestration runtime; hosted deployment and observability are separate choices.
Data boundary
You choose model, tool, checkpoint and tracing destinations. Enabling a hosted tracing service sends run details beyond your runtime.

Sources checked — LangGraph

External resource

Coding agents

OpenAI Codex

Explore a codebase, make changes and run development tasks through local clients or cloud workspaces.

  • Hosted service
  • Install a runtime
Requirements
Local clients require installation and supported sign-in: ChatGPT or an API key. Codex cloud requires ChatGPT sign-in; plan and workspace permissions govern access.
Where it runs
Local app/CLI/editor clients and cloud workspaces; local execution still uses configured model services.
Data boundary
Local files can become model context. Data settings depend on whether you use ChatGPT or API authentication, your workspace and connected services.

Sources checked — OpenAI Codex

External resource

Coding agents

Claude Code

Work on a code project through a terminal agent that can inspect files, edit and run commands.

  • Install a runtime
Requirements
Install the CLI and sign in using a supported Claude subscription, Claude Console account or supported cloud provider. You also need a code project and terminal.
Where it runs
This entry covers the local CLI described in the official quickstart.
Data boundary
Project context is sent to the configured model service. Review repository permissions, tool approvals and the data rules for your chosen account or provider.

Sources checked — Claude Code

External resource

Testing and evaluation

Promptfoo

Compare prompts and model outputs with datasets and configurable assertions.

  • Install a runtime
Requirements
Install the CLI to run evaluations. Model-backed tests require provider access; execution can incur provider charges. Our configuration builder does not execute it.
Where it runs
Local CLI and optional sharing services; not embedded in UTools.
Data boundary
Promptfoo runs separately; selected model providers can receive prompts and test cases. Review telemetry and provider settings before use.

Sources checked — Promptfoo

External resource

Tracing and observation

Langfuse

Trace agent runs, manage prompts and organize evaluations across your application.

  • Hosted service
  • Self-hosted server
Requirements
Use a cloud project or deploy the server, then connect your app through the SDK or supported integrations. Access and hosting costs depend on your setup.
Where it runs
Hosted project or a maintained self-hosted service.
Data boundary
Configured tracing can transmit prompts, outputs and metadata to your Langfuse deployment. Set redaction and access rules before collecting private data.

Sources checked — Langfuse

External resource

Tracing and observation

LangSmith

Inspect production traces and build datasets for debugging and evaluation.

  • Hosted service
Requirements
The documented hosted quickstart requires an account, project and API key, plus an SDK or framework integration. Check your plan and limits directly.
Where it runs
External hosted tracing; no connection has been configured here.
Data boundary
Tracing sends configured application activity to the service; decide what may be captured and who may view it.

Sources checked — LangSmith

External resource

Testing and evaluation

Ragas

Evaluate RAG and agent workflows using task datasets and explicit metrics.

  • Install a runtime
Requirements
Install the Python library and prepare suitable datasets. Model-graded or embedding metrics need the corresponding provider or local model runtime.
Where it runs
A development library, not a browser-only evaluator or a connected integration.
Data boundary
Data handling depends on the chosen metrics and model providers. A local Python process may still call external models.

Sources checked — Ragas

External resource

Knowledge and retrieval

LlamaIndex

Build ingestion, retrieval and agent workflows with explicit data connectors and storage.

  • Install a runtime
Requirements
A development environment is required. Choose and configure the data stores, embedding models and language models your workflow uses.
Where it runs
A framework for an application you run; our text splitter only prepares local chunks.
Data boundary
Connectors, storage, embeddings and language models each have their own data boundary. Review the complete path before adding private documents.

Sources checked — LlamaIndex

External resource

Browser and web data

Firecrawl

Convert selected web pages into structured or model-readable content through a separate service.

  • Hosted service
Requirements
The hosted API needs an account and API key. Check endpoint support, credits and target-site permissions before making requests.
Where it runs
External web-data service; its API is not connected to UTools.
Data boundary
Requested URLs and extracted content go through the chosen service. This directory never submits your URLs to Firecrawl.

Sources checked — Firecrawl

External resource

Browser and web data

Browser Use

Run browser tasks through a hosted agent, cloud browser or separately installed library.

  • Hosted service
  • Install a runtime
Requirements
Cloud use needs an API key; a local setup needs the library, browser and chosen model access. Check the official setup and billing for the selected path.
Where it runs
Cloud paths and a separate open-source library; no browser automation is launched here.
Data boundary
Browser sessions may expose page content and account state to the chosen runtime and models. Scope tasks and permissions in that platform.

Sources checked — Browser Use

Check three things before choosing a platform

Who operates the runtime

Hosted services start with an account. Self-hosting requires maintaining a server and storage. Code frameworks need a development environment. A local installation does not imply local model inference.

Where the data goes

Check model, plugin, search, MCP and tracing services. Self-hosting controls where the application runs; connected external services may still receive your inputs.

How you will verify it

Start with one small task to check tool calls, failure handling and human review points. Test exported configuration in the target platform and compare cost estimates with actual billing.

Scope: public official documentation and destinations checked on 2026-11-03. We did not sign in, install or run these services. Plans, regions, permissions and features can change; check the official pages. Resources are grouped editorially, without ratings or market rankings.

OpenAI Agent Builder is in a deprecation transition, with a scheduled shutdown on 2026-11-30 in the official documentation. This directory lists Agents SDK for developers who want to control agent workflows in their application. Read the official deprecation notice

AI datasets, response handling and evaluationBrowse all local tools