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

# Dev Mode

> Advanced editing for custom clauses (dynamic fields or raw JSON), manual system prompt, and evaluation strategy.

Dev Mode is for operators who need full control over **Custom Rules** (custom clauses), the **system prompt**, and **evaluation strategy** without the normal guardrails.

Turn **Dev Mode (advanced)** on with the switch in the **Custom Rules** header. That single flag unlocks advanced clause editing and, farther down the Profile section, the **evaluation strategy** selector and **system prompt** controls that are hidden in standard mode.

## Custom clauses: Dynamic Fields vs Raw JSON

With Dev Mode on, **Custom Rules** no longer use the compact default form. Instead you choose an **Editing mode**:

| Mode               | What you do                                                                                                                                                                                                                                    |
| ------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Dynamic Fields** | Every clause is its own **large text field**. You can **edit any value**, **remove a field** (including standard ones you do not need), and use **Add custom field** to create **new clause keys** beyond identity, personality, purpose, etc. |
| **Raw JSON**       | Edit the entire `custom_clauses` map as **JSON** in the code editor (valid object of string values). Use this for bulk copy/paste, merges, or scripted content.                                                                                |

In both modes the clauses object is **fully yours**: nothing is read-only, and fields you do not want can be **deleted** (Dynamic: per-field delete; Raw: remove keys from the JSON).

<Note>
  **Standard mode** only supports the usual fixed clause keys. Dev Mode is what makes **arbitrary keys** and **removals** possible.
</Note>

## Manual system prompt

With Dev Mode enabled, the **System Prompt** block appears. Turn on **Manage system prompt manually** to write the prompt yourself in the textarea instead of using auto-generated text from the clauses.

You can still insert `{{identity}}`, `{{personality}}`, etc. from the tag helper so the manual prompt **pulls live values** from whatever keys exist in Custom Rules (including custom keys you added in Dynamic Fields or Raw JSON).

## System prompt variables

| Variable              | Typical source clause |
| --------------------- | --------------------- |
| `{{identity}}`        | `identity`            |
| `{{personality}}`     | `personality`         |
| `{{purpose}}`         | `purpose`             |
| `{{knowledge}}`       | `knowledge`           |
| `{{rules}}`           | `rules`               |
| `{{response_format}}` | `response_format`     |

If you add custom clause keys, reference them in the manual prompt with the same `{{key}}` pattern.

Example:

```
<system>
You are {{identity}}.
Tone: {{personality}}

Your primary objective: {{purpose}}

Domain knowledge:
{{knowledge}}

Operating rules:
{{rules}}

Output format:
{{response_format}}
</system>
```

<Tip>
  This pattern works well for Claude-style models with clear XML sections. You keep clause content in **Dynamic Fields** or **Raw JSON**, and structure the prompt manually above.
</Tip>

## Evaluation strategy override

With Dev Mode on, Studio **stops auto-forcing** `react` when you add MCP servers or Agent-to-Agent links. You set **evaluation strategy** explicitly and it stays where you put it until you change it.

## Leaving Dev Mode

<Warning>
  **Disabling Dev Mode** returns Custom Rules to the **standard form**. If you added **extra clause keys** (not in the default set), Studio warns you that those fields will be **dropped** when you confirm; only the default clause keys are kept, with your values merged in. If you need that data, **copy Raw JSON** before switching off.
</Warning>

Turning Dev Mode off also **replaces a fully manual system prompt** with the **auto-generated** prompt from your clauses unless you have handled that separately — **copy anything you must keep** before toggling.

## When to use Dev Mode

* You need **custom clause keys** or want to **remove** standard clauses you do not use.
* You want **full JSON** control over clauses for migrations or diffs.
* You need a **fixed evaluation strategy** that must not be overridden by tool/A2A autoswitching.
* You are **authoring the system prompt by hand** and still want clause variables injected.

## Next steps

<Card title="Back to Agent Overview" icon="arrow-left" href="/platform/agent-creation/overview">
  Review the full wizard overview and what’s available in each step.
</Card>