Codex-Claude-Monitor

Codex-Claude-Monitor is a VS Code extension that tracks context usage for the current Codex or Claude Code session right in the status bar.

The extension reads local session files for both Codex and Claude Code, then displays whichever tool was active most recently. It makes no network requests — everything is computed from files already on your machine.

Features

• Unified status bar item for both Codex and Claude Code. The provider whose session file was updated most recently wins, so you never have to switch anything manually.
• Color-coded warnings that adapt to your theme as context fills up:
  • 🟢 green below 50%
  • 🟡 yellow at 50–79%
  • 🔴 red at 80% and above
• Minimal status bar showing just the active provider and context percentage, so it stays compact.
• Detailed hover tooltip with exact token counts, the friendly model name, Claude token composition and cache-hit rate, and Codex 5-hour / weekly rate-limit usage and reset times.
• Workspace-aware filtering — only sessions whose working directory lives inside your current VS Code workspace are counted, so CLI sessions from other projects are ignored.
• Click to refresh immediately, plus automatic refresh on a configurable interval.

Display

The status bar shows compact text such as:

Codex ⚡ 13%
Claude ⚡ 18%

• The leading label is the active provider, followed by the ⚡ lightning bolt and the context usage percentage.
• The friendly model name (e.g. Opus 4.8) and Codex rate-limit windows are kept out of the status bar and shown in the hover tooltip instead.
• The item color reflects context-usage severity (green / yellow / red, see above).
• Codex percentages come from input_tokens / model_context_window for the latest request.
• Claude Code percentages come from input_tokens + cache_read_input_tokens + cache_creation_input_tokens, divided by the inferred context window.

Hover the status bar item to see full detail. Codex shows 5-hour and weekly usage with reset times; Claude shows the friendly model name plus token composition and cache-hit rate:

Codex: ctx 136k / 258k (53%)
5h usage: 21% · Reset at 14:32
Weekly usage: 10% · Reset at 6/8 09:24

Claude: ctx 36k / 1m (18%)
Model: Opus 4.8 (1M context)
Tokens: input 2 · cache read 36k · cache create 411
Cache hit: 100%

Click the status bar item to refresh immediately without opening a notification. Detailed usage always stays in the hover tooltip.

Local Installation

This extension is meant for local use and is not published to the marketplace. Link this directory into the VS Code extensions directory:

ln -s /path/to/codex-claude-monitor ~/.vscode/extensions/codex-claude-monitor

Then run this command from the VS Code command palette:

Developer: Reload Window

After reload, Codex or Claude Code context usage appears on the right side of the status bar. You can also trigger a manual refresh at any time:

Codex-Claude-Monitor: Refresh

Configuration

Changing any of these settings refreshes the status bar and restarts the refresh timer immediately.

How It Works

Data flows from local session JSONL files → provider parsers (with workspace filtering) → most recently active provider → status bar.

Codex. The extension recursively scans ~/.codex/sessions for rollout-*.jsonl, picks the newest file by modification time, and reads the last token_count event. Files are matched to your workspace by reading each candidate's session_meta.payload.cwd.

~/.codex/sessions

Claude Code. The extension recursively scans ~/.claude/projects for .jsonl files, picks the newest, and reads the last type: "assistant" entry that carries message.usage. The context window is inferred from the model name (model names containing 1m, or claude-opus-4-7 / claude-opus-4-8, use 1M; everything else uses 200k). Workspace filtering uses Claude's munged directory names, so files don't even need to be open.

~/.claude/projects

Sessions whose working directory is outside the current workspace are ignored. An empty window disables workspace filtering and shows the latest global session.

Privacy

The extension only reads local session files. It does not make network requests, upload data, or collect telemetry.