Configure Claude Projects with instructions and knowledge sources

Key points

1. 1

   Projects are self-contained workspaces with their own chat history, project instructions and knowledge base. Chats inside a Project automatically use its instructions and knowledge.

2. 2

   Split configuration by purpose: project instructions hold short, always-on guidance (Claude's role, audience, tone, output format, constraints, what to do when information is missing); project knowledge holds the reference documents (guidelines, policies, specifications, templates).

3. 3

   Keep instructions concise and focused on general context, key guidelines and Claude's role. Pasting a 30-page guide or a nine-page handbook into instructions buries the rules that matter.

4. 4

   A rule buried in a knowledge file is reference material, not a standing instruction; constraints that must apply to every answer belong in instructions.

5. 5

   Use descriptive filenames (for example sow-2026-03.pdf, staff-list-2026-27.xlsx) and group related documents; it helps retrieval and lets people reference a document by name.

6. 6

   Keep unnecessary personal data out of knowledge: upload the documents the work needs, not raw customer or HR exports.

7. 7

   Project knowledge uses the chat context window. On paid plans, when knowledge approaches or exceeds the limit, retrieval (RAG) mode activates automatically, expanding capacity up to about 10x; Claude then searches the knowledge and pulls in the relevant parts rather than loading everything. No setup is needed.

8. 8

   Because retrieval fetches knowledge by relevance, short material that must shape every answer (a glossary, key definitions) is safer in instructions than in a large knowledge base.

9. 9

   Uploaded documents are cached, so reusing the same project knowledge across chats counts less against usage limits than re-pasting content.

10. 10

    On Team and Enterprise plans, Projects can be shared with individuals, in bulk by email list, or organisation-wide (where admins allow it). "Can view" lets members use the Project and chat in it; "Can edit" lets them change instructions, knowledge and members. Give edit rights only to maintainers.

11. 11

    Chats inside a shared or public Project stay private to the person who had them unless they share the chat explicitly.

12. 12

    The help centre notes that Google Drive files can be added as knowledge only in private Projects; for a shared Project, upload the files and agree a refresh routine.

13. 13

    Each Project has its own memory space, separate from non-project chats. Free accounts are limited to five Projects.

14. 14

    Do not create one Project per chapter or per user to work around a configuration problem; fragmentation multiplies maintenance and loses cross-document answers.

Read the source

• What are projects?
• How can I create and manage projects?
• Manage project visibility and sharing
• Retrieval augmented generation (RAG) for projects