> Fetch clean Markdown by appending `.md` to any page URL under https://signalwire.com/docs or requesting it with the HTTP header `Accept: text/markdown`. The root index at https://signalwire.com/docs/llms.txt lists the available documentation indexes.

# addPatternHint

> Add a speech recognition hint with pattern matching and replacement.

[ref-agentbase]: /docs/server-sdks/reference/typescript/agents/agent-base

Add a hint with pattern matching and replacement. This allows you to intercept
specific ASR output and rewrite it before it reaches the AI -- useful for correcting
consistent misrecognitions or normalizing variations.

## **Parameters**

**`opts`** `object` — required

Pattern hint configuration object with the following fields:

---

**`opts.hint`** `string` — required

Descriptive label for the hint (surfaced to the ASR alongside the pattern).

---

**`opts.pattern`** `string` — required

Regular expression pattern to match.

---

**`opts.replace`** `string` — required

Replacement text to substitute when the pattern matches.

---

**`opts.ignoreCase`** `boolean`

Whether to ignore case when matching the pattern.

---

## **Returns**

[`AgentBase`][ref-agentbase] -- Returns `this` for method chaining.

## **Example**

```typescript {6}
import { AgentBase } from '@signalwire/sdk';

const agent = new AgentBase({ name: 'support', route: '/support' });
agent.setPromptText('You are a helpful assistant.');
// Correct common ASR misrecognition
agent.addPatternHint({
  hint: 'SignalWire brand name',
  pattern: 'signal\\s*wire|signal\\s*wired',
  replace: 'SignalWire',
  ignoreCase: true,
});
await agent.serve();
```

> Add a speech recognition hint with pattern matching and replacement.