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.
Prepare locally. Choose where to run.
Use 18 browser-local tools for instructions, skills, context planning, MCP configuration, datasets and deterministic evaluation. Compare official external services by task and requirements.
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.
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.
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
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.
Turn your goal, project context and approval rules into an editable AGENTS.md or CLAUDE.md.
Open toolCreate a SKILL.md with safely quoted YAML metadata and your own reusable workflow.
Open toolBuild client-specific MCP JSON for Claude Desktop, Cursor or VS Code without running commands.
Open toolCheck MCP JSON syntax and supported client semantics, with precise paths for issues.
Open toolFill explicit {{variables}} in prompts, including nested fields and JSON-array batches.
Open toolInfer a draft 2020-12 JSON Schema from sample JSON and validate another value locally.
Open toolEstimate token charges from your own rates, tokens per step, step count and repeated runs.
Open toolArrange editable task dependencies and inspect a topological order and critical-path estimate.
Open toolCount exact o200k_base or cl100k_base text tokens locally, inspect token IDs and compare both vocabularies.
Open toolAllocate a user-defined context window across editable text segments, output reserve and extra overhead.
Open toolPrepare traceable text chunks with paragraph, line or fixed boundaries, a hard size cap and adjustable overlap.
Open toolConvert MCP JSON between Claude Desktop, Cursor and VS Code with explicit checks for fields that cannot be preserved.
Open toolMerge 2–10 MCP JSON files with server selection, custom names and explicit conflict strategies.
Open toolCompare MCP servers and fields with stable Added, Removed, Changed and Unchanged results and private values masked by default.
Open toolCheck existing model outputs with deterministic assertions, Unicode lengths and normalization settings.
Open toolCheck text conversations or input/output JSONL with physical line numbers and duplicate-ID detection.
Open toolWrap an inline JSON Schema for OpenAI Responses, Chat Completions or Anthropic tools.
Open toolPrepare a literal YAML config with prompts, provider IDs, variables and deterministic assertions.
Open toolExternal resource
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
Visual builders
Connect model steps, knowledge retrieval and tools in a visual application workflow.
Visual builders
Build assistants with prompts, knowledge, tools and workflows on the international Coze platform.
Agent workspaces
Use a Chinese-language Agent workspace for tasks, projects and collaboration, with skills, MCP and plugins.
Workflow automation
Connect triggers, business apps and AI steps into repeatable workflows.
Visual builders
Prototype agents and LLM flows with a visual node editor and reusable components.
Visual builders
Connect visual components into agent flows, then expose a flow through an API.
Code frameworks
Write agents, function tools and handoffs in JavaScript or Python while controlling the application runtime.
Code frameworks
Build tool-using agents and agent teams in code, and test them with a local CLI or development web UI.
Code frameworks
Coordinate role-based agents and use Flows to control state and execution order.
Code frameworks
Control stateful agent graphs with durable execution, streaming and human review points.
Coding agents
Explore a codebase, make changes and run development tasks through local clients or cloud workspaces.
Coding agents
Work on a code project through a terminal agent that can inspect files, edit and run commands.
Testing and evaluation
Compare prompts and model outputs with datasets and configurable assertions.
Tracing and observation
Trace agent runs, manage prompts and organize evaluations across your application.
Tracing and observation
Inspect production traces and build datasets for debugging and evaluation.
Testing and evaluation
Evaluate RAG and agent workflows using task datasets and explicit metrics.
Knowledge and retrieval
Build ingestion, retrieval and agent workflows with explicit data connectors and storage.
Browser and web data
Convert selected web pages into structured or model-readable content through a separate service.
Browser and web data
Run browser tasks through a hosted agent, cloud browser or separately installed library.
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.
Check model, plugin, search, MCP and tracing services. Self-hosting controls where the application runs; connected external services may still receive your inputs.
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