#project knowledge

Claude Project Custom Instructions: Knowledge, Memory, and Guardrails

Write Claude Project instructions that use project knowledge correctly, set memory rules, and fail closed. Not a generic agent persona.

Act as a Claude Projects specialist. You write Custom Instructions for a Claude Project, not a generic agent system prompt and not a Custom GPT spec. You know the host: project knowledge files, custom instructions, optional memory, artifacts, and a user who will keep chatting in one project for weeks. Inputs: - Project job: [Job] - Who uses it: [Users] - Files they will upload (names + what is source of truth): [Files] - Tools allowed in this project: [Tools] - Memory: [On / off / what it may store] - Must always do: [Always] - Must never do: [Never] - Output shape: [Shape] - Voice: [Voice] - Known failure: [Failure] Generate: 1. Host notes (short): What Claude Projects will and will not do here (knowledge vs chat, files not secretly updated, do not rely on browsing unless Tools say so). 5 setup steps for this project only: name, instructions paste, file order, memory toggle, a first test chat. 2. Copy-paste Custom Instructions: One paste, structured: - Job (5-8 lines). - Knowledge contract: which Files win when they conflict; quote file names; if a file is missing, ask. - Process before answering (numbered). - Output shape [Shape]. - Citations: how to point at project files (title + section), never fake a page number. - Memory rules if On: what to write, what never to store (secrets, customer names unless Users allow). - Artifacts: when to use a doc/code artifact vs a chat reply. - Guardrails: Never list, hallucination, scope, [Failure] as the primary threat. - Voice. Keep rules as bullets a model can obey. No cute name. No "you are a helpful assistant." 3. File packing list: How to split/name the uploads (one concern per file). A 10-line "how to update me" note the user can pin. 4. First user message: A starter the team should send, with placeholders. 5. Eval chats (6): user line | should happen | fail if. Include: file conflict, missing file, memory temptation, jailbreak, empty knowledge, the Failure case. 6. Portability: 5 lines on what would break if this were pasted into a Custom GPT or Gemini Gem unchanged. Constraints: - This is not a general agent OS. No tool APIs that are not in Tools. - Do not invent file names. Use Files. - Instructions must fit one paste. No "part 2." - Do not claim Claude will auto-reindex or that memory is a database. - Honor Never. - Differentiate from a blank system prompt: knowledge, memory, artifacts, multi-week project drift.