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

# Get Agent Function

> Fetch one custom function by ID.

<Warning>
  **Legacy endpoint - deprecated.** Unversioned endpoints are scheduled for removal on **July 31, 2026**. A public v1 replacement is not currently listed in the v1 reference. This endpoint remains available for existing integrations until then.
</Warning>

Returns one custom function by its primary ID.

## Path parameters

| Parameter       | Description           |
| --------------- | --------------------- |
| `agentId`       | Agent ID.             |
| `versionNumber` | Agent version number. |
| `functionId`    | Function ID.          |

## Related endpoints

* [Update Agent Function](/docs/api-reference/agent-functions/update): edit a function.
* [Delete Agent Function](/docs/api-reference/agent-functions/delete): remove a function.


## OpenAPI

````yaml GET /agent-functions/{function_id}
openapi: 3.0.0
info:
  title: DialNexa API
  description: >-
    Public REST API for the DialNexa voice AI platform. Versioned endpoints are
    under /v1; unversioned endpoints are legacy and deprecated.
  version: 1.0.0
servers:
  - url: https://api.dialnexa.com
    description: DialNexa production API
security:
  - bearer: []
tags:
  - name: API Keys
  - name: Agent Functions
  - name: Agents V1
  - name: Agents2
  - name: Batch Calls
  - name: Batch Calls V1
  - name: Call Logs
  - name: Calls
  - name: Calls V1
  - name: Campaign Leads
  - name: Campaigns
  - name: External Webhooks
  - name: Knowledge Base
  - name: Knowledge Base V1
  - name: LLMs
  - name: LLMs V1
  - name: Languages
  - name: Languages V1
  - name: Organization Phone Numbers
  - name: Organization Phone Numbers V1
  - name: Phone Number Pricing
  - name: Phone Number Pricing V1
  - name: Transcribers
  - name: Transcribers V1
  - name: User Webhooks
  - name: User Webhooks V1
  - name: V1
  - name: Voices
  - name: Voices V1
  - name: Webcall
  - name: Workflow Leads
  - name: Workflow Leads V1
  - name: Workflows
  - name: Workflows V1
paths:
  /agent-functions/{function_id}:
    get:
      tags:
        - Agent Functions
      summary: Get an agent function by its primary ID
      description: >-
        **Legacy endpoint - deprecated, scheduled for removal on July 31,
        2026.** Use the `/v1` version for new integrations. 
      operationId: AgentFunctionsController_findOne
      parameters:
        - name: function_id
          required: true
          in: path
          description: Primary ID of the agent function
          schema:
            type: string
      responses:
        '200':
          description: Agent function returned successfully.
        '401':
          description: Unauthorized.
        '404':
          description: Agent function not found.
      deprecated: true
components:
  securitySchemes:
    bearer:
      scheme: bearer
      bearerFormat: JWT
      type: http

````