> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zerotwo.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Project Instructions

> Set a custom system prompt for your project — injected automatically into every chat within it.

## What are Project Instructions?

Project instructions are a custom system prompt that ZeroTwo injects at the start of every chat within the project. They're the most powerful feature in projects: write your context, constraints, and preferences once, and every project chat inherits them automatically.

Think of project instructions as a standing briefing you give ZeroTwo before every conversation in the project.

## How to Set Project Instructions

<Steps>
  <Step title="Open the project">
    Click the project name in the left sidebar.
  </Step>

  <Step title="Open project settings">
    Click the **Settings** or gear icon in the project header.
  </Step>

  <Step title="Go to Instructions">
    Find the **Instructions** section or tab.
  </Step>

  <Step title="Write your instructions">
    Type your system prompt in the text area. Be as specific as your use case requires.
  </Step>

  <Step title="Save">
    Click **Save**. Instructions take effect immediately for all new chats in the project.
  </Step>
</Steps>

<Note>
  Instructions apply to **new chats** started after saving. Existing chats that were already open won't retroactively receive updated instructions.
</Note>

## Use Cases and Examples

### Coding assistant

```
You are a senior software engineer helping with our React/TypeScript e-commerce platform.

Stack: React 18, TypeScript 5, Tailwind CSS, Supabase, React Query.

Coding conventions:
- Use functional components with hooks only (no class components)
- Prefer const over let
- Use named exports (not default exports)
- Always include TypeScript types — no implicit any
- Follow Airbnb ESLint config

When reviewing code: point out both bugs and style improvements.
When writing new code: include brief inline comments for non-obvious logic.
```

### Creative writing project

```
You are helping me write a science fiction novel set in 2150 on Mars.

Story details:
- Main character: Zoe Chen, a 34-year-old geologist working for the Mars Geological Survey
- Setting: Olympus Station, a research colony of ~800 people
- Tone: Hard sci-fi with emotional depth — think Kim Stanley Robinson
- Current plot: Zoe discovers an anomalous mineral formation that suggests pre-human intelligent life

Always maintain consistency with established plot points. If I ask you to write something that contradicts established facts, flag it before proceeding.
```

### Research project

```
This project is for researching the electric vehicle market for a consulting report.

Scope: North American EV market, 2023–2026.

Guidelines:
- Always cite sources when making factual claims
- Format responses with clear section headings
- Focus on data-backed insights (market share, adoption rates, policy impacts)
- When data is unavailable or uncertain, say so explicitly
- Target audience: C-level executives with no prior EV industry knowledge
```

### Client work

```
This project is for Acme Corp's website redesign (Q1 2026 launch).

Client context:
- Acme Corp is a B2B SaaS company selling HR software to mid-market companies
- Brand voice: professional, approachable, outcome-focused
- Key differentiator: 60% faster onboarding than competitors
- Brand colors: #1A2B5A (navy), #F5A623 (amber)

All copy should be written for the client's website audience: HR directors at 500–5000 person companies.
Always default to active voice and avoid jargon.
```

## Tips for Effective Instructions

**Be specific about format.** If you always want bullet points, say so. If you want code with comments, specify that.

**Define the AI's role clearly.** "You are a senior TypeScript developer" gives the AI a clear persona to maintain. Vague role definitions produce inconsistent behavior.

**Include constraints.** "Only answer questions about this project — redirect off-topic questions" helps keep project chats focused.

**Update as the project evolves.** Your stack, scope, and preferences will change. Revisit instructions periodically and update them. Old, stale instructions can confuse more than they help.

**Keep it under 2,000 words.** Very long instructions consume a significant portion of the available context window, leaving less room for your actual conversation. Aim for comprehensive but concise.

## Interaction with Global Custom Instructions

ZeroTwo also applies your global custom instructions (set in **Settings → Personalization**) to every chat. Project instructions are applied **in addition to** global instructions — they don't replace them.

If there's a conflict between global and project instructions, project instructions generally take precedence for that project. If you notice unexpected behavior, check both settings for contradictions.