# Claude Code and the context window on bigger projects **Author:** Ivan Misic **Published:** 2026-02-01 **URL:** https://ivanmisic.net/blog/ai-tools/claude-code-context-window **TL;DR** On a large project, give each Claude Code session one task, name the likely files, and keep the project instructions current. - Use `/context` to see what fills the window, `/clear` when the task changes, and `/compact` when the same long task must continue - Name the file and visible problem so Claude starts in the right area instead of reading unrelated code - Turn repeated review or maintenance instructions into project skills under `.claude/skills/` - Break a large feature into small build and review steps, and use subagents only for independent analysis with a clear expected result - Rename, move, or consolidate the source when repeated confusion shows the project structure itself is the problem My website is now close to a thousand files, so I no longer ask Claude Code to "fix the page." I give each session one task and name the files involved, as similar components now exist in several folders. ## Context Management: Fresh Sessions My first rule is to start a fresh session for each new task. A new session loads the project instructions without the assumptions from the previous task. I use `/clear` when I want to reset the conversation in the same terminal. If the task must continue, `/compact` keeps a shorter version of the context. I choose a fresh session when the work changes, because old context can point Claude toward the wrong files or decisions. Before deciding which of those I need, I run `/context`. It shows what is actually filling the window, and the answer is often one large file read rather than the conversation itself, which is a different problem with a different fix. `/autocompact` sets how much room to leave before Claude compacts on its own. ## Be Specific About Files With five files, "fix the header" probably means one thing. With fifty files, it could mean any of ten different headers. I name the file and the visible problem: ```text In pages/contact.html, fix the header spacing. The heading is too close to the navigation bar. ``` Not: ```text Fix the header spacing. ``` Claude can search the project, but naming the likely file gives it a better starting point and avoids reading unrelated code. ## Reusable Skills Pay Off at Scale I turn repeated project checks into skills, as I do not want the review criteria to change between sessions. For example: - **review** runs the same code-review checklist - **check-links** checks navigation and links - **mobile** checks each page at mobile width Put a repeated checklist in a project skill so the team can run the same review each time. Existing `.claude/commands` files still work, but new reusable workflows belong in `.claude/skills//SKILL.md`. ## Break Big Tasks into Steps "Add a blog section to the website" is a big ask. It involves creating templates, styling, navigation updates, content, and possibly restructuring your project. Break it into pieces: ``` Step 1: Create a blog listing page at blog/index.html that shows a list of post titles and dates. Use the same style as the rest of the site. No actual posts yet, just the listing page structure. ``` Review the first result before asking for the next part. Then continue with the second task: ``` Step 2: Create a template for individual blog posts at blog/post-template.html. It should have the post title, date, content area, and a back link to the blog listing. ``` Review that result, then continue with the next small task. Each step is small enough to review thoroughly. If something goes wrong, you know exactly where it happened. If you need to undo, you only lose one step, not the whole thing. ## Agents for Big Analysis When you need to analyze or check something across many files, tell Claude to use parallel agents (Module 2, Chapter 7): ```text Use parallel agents to check all HTML pages for: - Missing page titles - Missing meta descriptions - Broken image paths - Links that don't go anywhere Work through all files and give me one combined report. ``` Use separate subagents for independent checks, then combine their findings in the main session. They can run concurrently, but each uses its own context and increases token usage. Do not split work that needs the same files or a shared decision. For a mechanical change that has to happen in many places at once, such as renaming a class across every page, `/batch` is built for that shape of work. It is worth reaching for only when the change is genuinely repetitive, because a task that needs judgment per file is not a batch. If a project grows past one repository, or into a monorepo, Anthropic's [guide for large codebases](https://code.claude.com/docs/en/large-codebases) covers how to lay out instructions and rules so the right ones load in the right place. ## CLAUDE.md Grows With Your Project Small project CLAUDE.md: ``` Personal portfolio website. Dark theme. Four pages. ``` Bigger project CLAUDE.md: ```bash # Portfolio & Blog ## Structure - pages/ - Static pages (home, about, projects, contact) - blog/ - Blog listing and posts - css/ - Stylesheets (main.css, blog.css) - images/ - All images - js/ - JavaScript (if any) ## Design - Dark theme (#0f172a background) - Accent: #38bdf8 - Font: Inter - Max width: 900px ## Important - Blog posts use blog/post-template.html as the base - Navigation is consistent across all pages - New pages must include meta title and description - All images go in images/ with descriptive names ``` Update `CLAUDE.md` when the structure or project rules change, so Claude starts each session with the current information. ## Signs Your Project Needs Structure Cleanup I update the project structure when the same confusion appears more than once: - Claude edits the wrong file because similar files have unclear names. - I cannot find a file without searching several folders. - The same style is defined in several places. - `CLAUDE.md` no longer matches the current structure. At that point I rename, move, or consolidate the source before adding more instructions. When you notice these, ask Claude to help: ``` Audit the project structure. Are there files in the wrong places? Duplicate styles? Anything that would confuse someone seeing this project for the first time? Suggest improvements. ``` ## How I Work on a Big Project I also break every big feature into small tasks. "Add a tools section" becomes: create the model, create the controller, create the listing view, create the detail view, add the routes, update navigation. Each task gets its own session. I no longer try to cover the whole project in one session. One task per session works, provided the project instructions are current. ## Frequently Asked Questions ### How do I see what is filling Claude Code's context window? Run `/context`. It shows what is taking up the window. Often it is one large file, not the conversation, so the fix is different. ### What is the difference between /clear and /compact? `/clear` gives you an empty context and saves the previous conversation so you can resume it later. Project instructions load again. `/compact` keeps a shorter version of the current context, which is what you want when the same long task has to continue. I use `/clear` when the work changes. ### Does Claude Code read every file in my project? No. It searches and reads the files the current task needs, which is why naming the likely file gives it a better starting point than a general description of the problem. ### How do I stop Claude Code from editing the wrong file? Name the file and the visible problem in the same sentence. On a project with fifty files, "in pages/contact.html, fix the header spacing, the heading is too close to the navigation bar" leaves far less room for interpretation than "fix the header spacing." ### When are subagents worth using? Use them for independent checks that can run at the same time, then combine the findings in the main session. Each subagent carries its own context and adds token usage, so do not split work that needs the same files or a shared decision.