Description
Use LLM Custom when you need to extract several fields from the current conversation in one call. It is best for small, flat groups of related values, such as contact details or claim details. Use LLM Data instead when you only need one value.Manual Inputs
| Name | Data Type | Required | Description |
|---|---|---|---|
| Reasoning | string | No | LLM reasoning effort (low, medium, high). Defaults to low |
| Transcript | string | No | How much conversation history to read. Defaults to Full |
| System Prompt | string | No | Instruction that applies to every field |
| Schema JSON | json | Yes | The flat fields the tool should return |
| Response Map | object | No | Where to write each extracted field |
Reasoning
How hard the model works to interpret the information.low— fields are directly statedmedium— the caller may imply values or answer in a messy wayhigh— fields need careful normalization, or there are competing details (can be slower)
Transcript
How much conversation history the tool reads:Full, or the last 2, 4, 6, 8, or 10 messages.
- Use
Last 2/Last 4when fields should come from the caller’s latest answer. - Use
Last 6/Last 10when values may be spread across a short exchange. - Use
Fullwhen earlier context matters — avoid it for simple extraction, since older details can confuse the result.
System Prompt
Optional instruction that applies to every field. Appended before the transcript and schema.Schema JSON
One parent JSON object. Each key is a flat output field. Each value must includetype and description.
| Type | Meaning |
|---|---|
string | Text |
number | Decimal number |
integer | Whole number |
boolean | True or false |
array | A list — include an items definition for the item type |
null | Usually combined with another type when a field may be missing |
["string", "null"]) when the customer might not provide a value.
Keep the schema flat. Do not nest objects — use field names like customer_email instead of customer.email. Do not include wrapper fields such as schema, required, or additionalProperties; the tool adds those internally.
Response Map
Optional. Maps each destination variable to the field name returned by the schema. The left side is the destination variable; the right side is the extracted field name.Manual Outputs
| Name | Data Type | Description |
|---|---|---|
| result | bool | true if the LLM returned schema-valid JSON and configured writes succeeded |
Conditions
Success (true)
The LLM returned valid JSON matching the schema. If a Response Map is configured, fields are written to their destinations.Failure (false)
The schema was invalid, the transcript was empty, or extraction failed.Example Usage
Contact details:Common Issues
- Schema fails validation — check that every field has both
typeanddescription. - Unsupported type error — use
string,number,integer,boolean,array, ornull. - Array fields fail — add an
itemsdefinition describing the list item type. - Nested objects fail — flatten the schema into top-level fields.
- Wrong value is written — check the Response Map field name on the right side.
- Noisy extraction — reduce Transcript and make field descriptions more specific.
Next Steps
- LLM Data — Extract a single typed value
- LLM Tools overview — When extraction passes vs fails
- Variables — See all available variables

