Codex CLI Context Usage: How to Check Available Space

To see context usage in Codex CLI, enter /status inside the interactive session and inspect its context information. A context indicator can also keep remaining space visible while you work. This reading concerns the session's working space, which is different from your account allowance or bill.

fenbs keeps durable project decisions and progress outside that active conversation, so you can bring back the relevant work when starting again. It does not measure Codex tokens or enlarge the context window. First identify the number you need, then decide whether the session needs less material or a clearer handoff.

How do you inspect the current session?

1. In the Codex composer, enter /status. This is a session command, not a command to run at your shell prompt.
2. Read the active model and context information together. Keep any account-limit reading separate.
3. Check the wording of the indicator: a percentage remaining and a percentage used describe opposite directions.
4. Note the reading before the next substantial task, then compare afterward if you are investigating growth.

The official OpenAI command reference↗ (opens in a new tab) documents session status, the status-line picker, and context compaction. For the broader command list, use the Codex CLI commands guide. You do not need to change your model or permissions just to inspect the readout.

What does the context reading actually mean?

A token is a small unit of text the model processes. The context window is the space available for one request, including its input and room for the response; reasoning can also count. OpenAI explains these boundaries in its conversation-state documentation↗ (opens in a new tab).

Read a percentage as a capacity signal, not a quality score. Plenty of room does not mean the instructions are clear, and a busy window does not prove the answer is wrong. If your actual concern is an account restriction, the separate Codex usage limits guide covers that question.

How can you work out what is taking space?

Start with the material you just asked Codex to inspect. A giant error log, repeated file dumps, or several unrelated investigations are good places to look. Treat changes in the total reading as clues; do not assume the status view is a precise per-file storage report.

• Look for repeated output. Ask for the relevant failure and nearby lines rather than another complete log.
• Narrow repository searches to the directories and symbols connected to the task.
• Identify the current source file or approved document instead of pasting several conflicting versions.
• Separate a finished investigation from the next unrelated task, carrying over only what the new task needs.

For example, if a single failing test produces pages of setup output, ask for the assertion failure, stack trace, and relevant test file first. More material may be necessary, but add it to answer a specific question. This makes the investigation easier for you to review as well.

Avoid asking Codex to invent an exact token breakdown by file. Prefer an observed readout plus a short account of what was read. Keep stable decisions in fenbs project context, and request the relevant ones when the next session begins.

Can you keep remaining context visible?

Use /statusline to choose context-related footer fields from the interactive picker. Keep the displayed model nearby if it helps you interpret the reading. The picker saves its choices; the configuration reference↗ (opens in a new tab) documents the ordered footer setting as tui.status_line.

Choose a small set of readings you will actually use. A constantly visible number is helpful when it prompts a decision: narrow the next search, save the current findings, or stop combining unrelated work. Watching it after every sentence usually adds little to a straightforward task.

When should you compact or start fresh?

/compact summarizes earlier chat to free context. /new starts a fresh chat. Use the former when you are continuing the same objective; consider the latter when the next task has little need for the previous conversation.

Before either transition, check that your reusable record says what is complete and what remains uncertain. A summary should not turn a suggested fix into a tested fix. Keep the actual files and verification results as the evidence, then explain the next action in a few concrete sentences.

Goal: fix the empty search result state.
Changed: the result component and its focused test.
Verified: the focused test passes.
Not verified: full application checks and phone layout.
Next: inspect the empty state on a narrow screen.
Constraint: preserve the approved wording.

Do not wait for a particular percentage to save this. A good stopping point in the work is often a better trigger than a capacity threshold. The Codex CLI best practices guide covers the wider habits that make sessions easier to review.

How to do this with fenbs

1. Create a free account and add the project you are working on in Codex.
2. Record the approved decisions and ongoing constraints in Decisions and rules. Keep current task findings in the task and AI context notes.
3. Connect Codex using the integration guides, then ask it to read the project context at the start of a session.
4. Before stopping, have the assistant save Where we left off with completed work, remaining checks, and the next action.
5. When you start a fresh conversation, ask it to read that context and inspect the relevant files before continuing.

fenbs is not the right fit if your only need is a live token meter. Use Codex's own session display for that. fenbs helps when the decisions and unfinished work need to survive a conversation change.

What if your context display is missing or different?

Type / to inspect the commands available in your installed CLI. Check your version against the official documentation before copying instructions for another interface. A desktop screenshot or an older terminal guide may show different controls.

If you report a display problem, include the version, the indicator label, and the action after which it changed. Remove private paths and project content from shared screenshots. For more on keeping the active prompt useful, browse the context engineering guides.