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

# Prompt writing fundamentals

# Prompt writing fundamentals (agent **Prompt & Goals**)

“Prompt” in the voice product means the **combined instructions** you enter in **Step 4 — Prompt & Goals** of the agent wizard, plus any **Platform rules** pack you select, **not** the post-call analysis templates on the **Call analysis prompts** page (those run on transcripts after the call).

![Prompt and Goals step with Identity, flow sections, and total prompt size counter.](https://mintcdn.com/callaro-docs/1fJs_sKJdgiwY8nj/images/scripts-ai/prompt-writing-fundamentals.png?fit=max\&auto=format\&n=1fJs_sKJdgiwY8nj\&q=85\&s=e652dd59b182e179e713227a59010301)

**What the static should show:** Step 4 with **Identity** and at least one of **Call control & flow** / **Discovery** visible, plus the **Total prompt** counter.

## Structure you can rely on

The editor is split into explicit blocks (each merged into the runtime prompt with the section names shown in the in-app help):

| UI section | Purpose |
| - | - |
| **Greetings** | Separate **inbound** vs **outbound** *Greeting text* and *Follow-up question*. |
| **Identity** | Persona / company / tone. |
| **Knowledge base** | Custom notes or a **linked** published knowledge base (when your plan allows). |
| **Call control & flow** | Pacing, what to do when busy or skeptical. |
| **Objection Handling** | Pushbacks and responses. |
| **Discovery & Qualification** | Questions and disqualification signals. |
| **Close / CTA** | Next steps and asks. |
| **Guardrails & Do's and Don'ts** | Compliance and boundaries. |
| **Tenant platform rules pack** | Optional; picks a row from **Platform rules**. |
| **Advanced** (collapsed) | **Custom instructions (system\_instruction)** and **Style addendum**. |
| **Conversation goals** | Numbered goal lines. |

## Limits and placeholders

* **Total prompt** size is capped (40,000 characters for all sections + goals + custom instructions, per product limits). The step shows a counter and blocks navigation/save when over limit.
* Greetings support `{{variable}}` names from **Step 3**; `{{caller_name}}` is called out in the UI as auto-filled from pre-call data when available.

## Platform rules vs agent text

**Platform rules** on the **Platform rules** page are tenant-wide packs suggested for new agents and merged **first** in the system prompt. Use them for disclosure and policy; use **Step 4** for persona, offer, and conversation design.

## Call analysis prompts (different feature)

**Call analysis prompts** (same **Call analysis prompts** page in the app) configure **post-call** LLM analysis (provider/model, template variables like `transcript`, `disposition`, etc.). Attach them in **Default tools** (Step 7) when you want structured output **after** the call. They do **not** replace Step 4 for live conversation.

![GIF media slot](https://mintcdn.com/callaro-docs/1fJs_sKJdgiwY8nj/images/scripts-and-ai/slot-01.gif?s=4ce942ed17100456c3f9b91cf9013cc8)

**What the GIF should show:** Adding a **Conversation goals** row or expanding **Advanced** custom instructions.

![Video media slot](https://mintcdn.com/callaro-docs/1fJs_sKJdgiwY8nj/media/scripts-and-ai/slot-01.mp4?fit=max\&auto=format\&n=1fJs_sKJdgiwY8nj\&q=85\&s=ced733e32205d7a1bd111ffa66886cbd)

**What the video should show:** Side-by-side mention: **Prompt & Goals** vs **Call analysis prompts** page headers to avoid confusing the two.

## Inbound calls

Inbound calls receive an additional set of runtime variables (`routing_reason`, `campaign_id`, `task_id`, `contact_id`, `follow_up_id`, `direction`) so your prompt can branch the greeting based on what the caller is returning to. See [Inbound runtime variables](https://help.callaro.ai/scripts-and-ai/inbound-runtime-vars.md) for the full list and sample prompt snippets.

## Related articles

* [Customising your call script](https://help.callaro.ai/scripts-and-ai/customising-your-script.md)
* [How the AI handles calls](https://help.callaro.ai/scripts-and-ai/how-the-ai-handles-calls.md)
* [What happens when a human answers vs voicemail](https://help.callaro.ai/scripts-and-ai/human-vs-voicemail.md)
* [Reviewing agent performance](https://help.callaro.ai/scripts-and-ai/reviewing-agent-performance.md)
* [Inbound runtime variables](https://help.callaro.ai/scripts-and-ai/inbound-runtime-vars.md)
* [Knowledge bases](https://help.callaro.ai/scripts-and-ai/knowledge-bases.md)


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