By default Claude is trained to be agreeable. This system prompt resets that. Works best in Settings → Global Instructions so it applies to every session.
Claude's context window is a spotlight, not storage. More tokens doesn't mean Claude remembers more — the spotlight gets dimmer. This is sometimes called "context rot."
Symptoms of context rot:
Fixes in Cowork:
- Start a new session when switching tasks. Reference your key decisions at the top of the new session so Claude has them fresh.
- Write a spec file for complex projects. A well-written 1-page brief in your workspace beats re-explaining across 30 messages.
- Use your memory files (decisions.md, preferences.md) — Claude reads these fresh every session, bypassing the rot entirely.
- Keep Global Instructions tight. Over 300 words = token tax on every request. Trim ruthlessly.
If you use Claude Code (CLI):
/compact (compress history), /clear (full reset), and /rewind (roll back state). These are developer CLI commands — not available in Cowork or the web interface.- ABOUT ME/ — about-me.md (background), my-voice.md (tone + phrases you never use), my-rules.md (ask first, show a plan)
- PROJECTS/ — one subfolder per project with a brief.md inside
- TEMPLATES/ — reusable prompt templates for your repeated tasks
- OUTPUTS/ — everything Claude generates, never your originals
- MEMORY/ — decisions.md, people.md, preferences.md (read every session)
Global Instructions (paste this exactly):
- Edit, don't restart. Edit previous messages rather than starting a new chat.
- New chat every ~15 messages. Shorter sessions = more headroom per session.
- Batch into one message. Combine follow-ups. One message, one response.
- Turn off Extended Thinking when you don't need deep reasoning — it burns tokens fast.
- Pace your day. Don't burn your quota in the first session of the morning.
Skills work automatically based on what you ask for. You don't need to name them.
- "Write a report on…" → Claude uses the docx skill → saves a real .docx to your folder
- "Make a presentation about…" → pptx skill → saves a real .pptx file
- "Build me a spreadsheet for…" → xlsx skill → saves a real .xlsx with formulas
- "Save this as a PDF" → pdf skill → creates a formatted PDF
- "Remind me every Monday to…" → schedule skill → sets up a recurring task
- "Build a skill for my most-repeated task" → skill-creator → interviews you, builds it
MCP (Model Context Protocol) connectors let Claude read and act on data from your real tools — Slack messages, Gmail threads, Notion pages, GitHub issues, databases, and more.
How to install:
- In Cowork, click Settings → Plugins or the plugin icon in the sidebar.
- Browse the marketplace or search for the tool you want to connect.
- Click Install. Authenticate with OAuth or paste an API key.
- Done. Claude can now read from and act on that service.
What you can do once connected:
- Slack: "Summarize what happened in #general this week." "Draft a message to the team about the launch."
- Gmail: "Find all emails about the Johnson account and summarize them." "Draft a reply to the last email from Sarah."
- Notion: "Pull the project brief from Notion and turn it into a presentation."
- Asana/Linear: "What tasks are assigned to me? What's overdue?"
- GitHub: "Summarize open PRs and flag anything that's been stale for over a week."
When Claude answers a question that you'll want to check again — open tasks, weekly metrics, project status — ask it to turn the answer into an artifact. This creates a persistent HTML page that lives in your Cowork sidebar and can pull fresh data each time you open it.
When to request an artifact:
- Any status page you'll check more than once (project tracker, hiring pipeline, support queue)
- Recurring reports — weekly metrics, team digest, budget summary
- Interactive data explorers — filter tasks by status, search a table, drill into records
- Any answer Claude just gave as a markdown list that you'll want refreshed tomorrow
How to request one:
Scheduled tasks let Claude run a job automatically on a schedule — daily summaries, weekly reports, recurring reminders — without any developer setup or cron jobs.
What to say:
Good use cases:
- Weekly digest of Slack / email highlights
- Daily agenda pulled from Google Calendar
- Monday morning task review from Asana or Linear
- Monthly metrics report from a connected database
- Recurring reminders to review decisions.md entries
Claude can read and analyze files you attach — screenshots, photos, PDFs, spreadsheets, CSV files, and more. This is one of the most underused features.
- Screenshot of an error → "What's wrong here and how do I fix it?"
- Photo of a whiteboard → "Turn this into a structured action list."
- PDF contract → "Summarize the key obligations and any red flags."
- Excel file → "Analyze this data and identify trends."
- Screenshot of a UI → "What UX issues do you see and how would you fix them?"
- Photo of handwritten notes → "Transcribe and organize these."
- Plan Mode Default: Use for any non-trivial task (3+ steps). Stop and re-plan immediately if something goes wrong.
- Subagent Strategy: Use subagents to keep main context clean. Offload research and parallel analysis.
- Self-Improvement Loop: After every session, update tasks/lessons. Iterate on failing tests until they pass.
- Verify Before Done: Diff changes, run tests, check logs. Demonstrate correctness before claiming complete.
- Demand Elegance: Ask "Is there a more elegant way?" Don't push unseen solutions.
- Zero Handholding: Fix bugs at root cause. Zero context switching required from user.
- Task Management: Write a checkable plan first. Explain changes. Capture lessons.
- Extract Architecture — Claude reverse engineers its own code into a master markdown file.
- Boundary Testing — Force failing unit tests for all auth and payment paths.
- Establish Telemetry — Integrate error logging (Sentry etc.) to catch silent failures.
- Refactor for Modularity — Break monolithic files into single-responsibility modules.
- Sanitize Dependencies — Audit every imported library for vulnerabilities.
- Document Deployment — Create a containerized build script.
- Threat Model — Run an adversarial AI agent to find injection flaws before hackers do.
Before Claude starts, have it identify what it actually needs to know. This eliminates the biggest source of bad output: Claude making assumptions instead of asking.
The prompt:
Power variation:
Instead of describing the format you want, show Claude 2–3 examples of the exact output. Claude's pattern matching is exceptional — it will nail your format, tone, and structure on the first try.
Template:
When your prompt has multiple parts, wrap each section in XML tags. Claude was trained on structured data and natively understands XML hierarchy — it attends to each section more accurately.
Template:
After Claude gives you an answer, ask it to critique its own response. It finds gaps and missing angles it didn't catch the first time. The second pass is almost always noticeably better.
Basic (one follow-up):
Full loop (build into the original prompt):
For important decisions:
Claude has strong default behaviors — bullet points, hedging, summaries, corporate-speak. Explicitly prohibiting these breaks habits faster than trying to describe the style you want.