Agent Monitor: Track Token Usage and Cost for Codex and Claude Code Agents

Melvin Vivas · X video post · 2026-09-16 · 0:01 · 2,236 views · Open on X

Topics: LLMOps, Deployment & Monitoring, AI Dev Tools & Productivity, AI Agents, Tool Use & MCP · Level: intermediate

Summary

Melvin Vivas shows Agent Monitor, his open-source dashboard for watching coding-agent sessions. It shows token usage with a per-agent breakdown and an estimated cost for the main agent and its subagents. It works with OpenAI Codex, Claude Code and Pi. The project is still in development, but you can already use it.

Key points

• Agent Monitor is an open-source GitHub project (donvito/agent-monitor) for visualizing coding-agent sessions.
• It shows a dashboard of the main Codex agent and its subagents.
• It shows token usage broken down per agent, plus an estimated cost.
• It supports Codex, Claude Code and Pi.
• According to the repo description, it also has an advanced traces view.
• It is still in development but already usable. It's a practical way to see where tokens and money go in multi-agent coding workflows.

Resources mentioned

• donvito/agent-monitor · repo · github.com · free
  Open-source dashboard that visualizes Codex and Claude Code subagents, with a traces view, a token breakdown and estimated cost.
  Also in: Monitor Codex and Claude Code Subagents with agent-monitor (Melvin Vivas on X · notes), Agent Monitor: see traces, tokens and costs of your coding agents (Melvin Vivas on X · notes), Agent Monitor: Visualize Codex and Claude Code Subagents, Traces and Costs (Melvin Vivas on X · notes), Agent Monitor: Visualize Coding-Agent Subagents, Traces and Costs (Melvin Vivas on X · notes) and 2 more
• OpenAI Codex · tool · openai.com · paid
  OpenAI's coding agent. In the diagram it writes code, fixes review findings and drives the build loop. The creator also used it to make this video.
  Also in: An agent bot that installs and drives Codex on its own (Melvin Vivas on X · notes), Asking a Coder bot to install Codex (Melvin Vivas on X · notes), Sign in with ChatGPT: Setting Usage Limits for Each App (Melvin Vivas on X · notes), Codex Cloud Environments Must Be Saved & Published Before Use (Melvin Vivas on X · notes) and 240 more
• Claude Code · tool · code.claude.com · paid · recommended by both Bashiri Smith & Melvin Vivas
  Build agents and pipelines from the terminal; the guide's main agentic coding tool.
  Also in: Create Claude Code Plugins with /plugin-authoring (Melvin Vivas on X · notes), Claude Code mods: customize behavior and UI with plugins (Melvin Vivas on X · notes), AI Engineer Roadmap Overview: From ML Foundations to RAG, Agents & Ops (Bashiri Smith on Facebook · notes), SkillsBento: Free Plugin Marketplace for Codex and Claude Code (Melvin Vivas on X · notes) and 101 more
• Pi · tool · x.com · free
  A customizable coding agent that can be extended through its Extensions API and connected to several model providers.
  Also in: Sign in with ChatGPT: Setting Usage Limits for Each App (Melvin Vivas on X · notes), Pi reaches v1.0 (Melvin Vivas on X · notes), Claude Code mods: customize behavior and UI with plugins (Melvin Vivas on X · notes), Customizing Your Coding Setup with Pi Coding Agent Extensions (Melvin Vivas on X · notes) and 39 more

Try this

• Try Agent Monitor from the GitHub repo to see token usage and estimated cost for your Codex, Claude Code or Pi sessions.