Get search results from StreamAssist

In your web app, you can get answers to your questions in the form of streaming responses. This document shows you how to use the REST API to get answers. If you want to use the Gemini Enterprise web app, see Chat with the assistant.

StreamAssist overview

StreamAssist provides a powerful, interactive way to handle user queries. It operates in a streaming fashion, enabling real-time, back-and-forth interactions.

The key capabilities of the API include the following:

• Maintaining conversational context: it uses sessions to maintain conversational context, ensuring it understands follow-up queries within the scope of previous interactions.

• Incorporating provided files: it includes the attached files as context for more informed and relevant responses.

• Seamless integration: it integrates with various agents and tools to fulfill a wide range of user requests.

Before you begin

Ensure that you have the following:

• The Discovery Engine API enabled for your Google Cloud. You can enable it on the Discovery Engine API page in the Google Cloud console.

  Go to Discovery Engine API

• A Discovery Engine role that has the discoveryengine.assistants.assist permission assigned to it.

• An existing Gemini Enterprise app. To create an app, see Create an app.

Get search results

You can use the streamAssist method to query and get answers from Gemini Enterprise. The following curl command lists the mandatory fields.

REST

curl -X POST \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
-H "Content-Type: application/json" \
"https://ENDPOINT_LOCATION-discoveryengine.googleapis.com/v1/projects/PROJECT_ID/locations/LOCATION/collections/default_collection/engines/APP_ID/assistants/default_assistant:streamAssist" \
  -d '
{
  "query": {
    "text": "QUERY_TEXT_1"
  }
}'

Replace the following:

• ENDPOINT_LOCATION-: the multi-region for your API request. Assign one of the following values:
  • us- for the US multi-region
  • eu- for the EU multi-region
  • global- for the Global location
  For more information, see Specify a multi-region for your data store.
• PROJECT_ID: the ID of your Google Cloud project.
• APP_ID: the unique identifier for the Gemini Enterprise app.
• LOCATION: the multi-region of your data store: global, us, or eu
• QUERY_TEXT_1: the search query text.

Example command and result

curl -X POST \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
-H "Content-Type: application/json" \
"https://global-discoveryengine.googleapis.com/v1alpha/projects/my-project-123/locations/global/collections/default_collection/engines/my-app/assistants/default_assistant:streamAssist" \
  -d '
{
  "query": {
    "text": "By when do corporations need to file taxes?"
  }
}'

{
  "answer": {
    "name": "projects/my-project-123/locations/global/collections/default_collection/engines/my-app/sessions/123456789013/assistAnswers/123456789019",
    "state": "SUCCEEDED",
    "replies": [
      {
        "groundedContent": {},
        "replyId": "123456789050"
      },
      {
        "groundedContent": {},
        "replyId": "123456789050"
      }
    ],
    "diagnosticInfo": {
      "plannerSteps": [
        {
          "createTime": "2025-11-24T22:21:13.958569117Z",
          "queryStep": {
            "parts": [
              {
                "text": "By when do corporations need to file taxes?"
              }
            ]
          }
        },
        {
          "createTime": "2025-11-24T22:21:17.218914056Z",
          "planStep": {
            "parts": [
              {
                "text": "**Formulating the Query**\n"
              }
            ],
            "planStepId": "123456789050",
            "role": "MODEL"
          }
        },
        {
          "planStep": {
            "parts": [
              {
                "text": "**Refining the Response**\n"
              }
            ],
            "role": "MODEL",
            "planStepId": "123456789050"
          },
          "createTime": "2025-11-24T22:21:19.734447578Z"
        },
        {
          "createTime": "2025-11-24T22:21:21.940682307Z",
          "planStep": {
            "planStepId": "123456789050",
            "role": "MODEL",
            "parts": [
              {
                "text": "**Processing the Results**\n"
              }
            ]
          }
        },
        {
          "planStep": {
            "role": "MODEL",
            "parts": [
              {
                "text": "**Querying and Analyzing**\n**Structuring the Answer**\n"
              }
            ],
            "planStepId": "123456789050"
          },
          "createTime": "2025-11-24T22:21:25.058155923Z"
        },
        {
          "createTime": "2025-11-24T22:21:25.955761161Z",
          "planStep": {
            "planStepId": "123456789050",
            "role": "MODEL",
            "parts": [
              {
                "text": "**Refining the Details**\n"
              }
            ]
          }
        },
        {
          "createTime": "2025-11-24T22:21:25.967576803Z",
          "planStep": {
            "role": "MODEL",
            "parts": [
              {
                "text": "Of course, I can help with that. The deadline for corporations to file their federal income tax returns depends on the type of corporation.\n\n### **Corporate Tax Filing Deadlines**\n\n| Corporation Type | Deadline | For Calendar Year-End (Dec. 31) |\n| :--- | :--- | :--- |"
              }
            ],
            "planStepId": "123456789050"
          }
        },
        {
          "createTime": "2025-11-24T22:21:25.988820408Z",
          "planStep": {
            "planStepId": "123456789050",
            "role": "MODEL",
            "parts": [
              {
                "text": "\n| **C Corporations** | 15th day of the fourth month after the end of their fiscal year. | April 15 |\n| **S Corporations** | 15th day of the third month after the end of their fiscal year. | March 15 |\n\n---\n\n###"
              }
            ]
          }
        },
        {
          "createTime": "2025-11-24T22:21:26.016095651Z",
          "planStep": {
            "planStepId": "123456789050",
            "role": "MODEL",
            "parts": [
              {
                "text": " **Extensions**\n\nIf a corporation needs more time to file, it can request a six-month extension by filing the appropriate form with the IRS. It's important to note that an extension to file is not an extension to pay. Taxes are still due by the original deadline.\n\nWould you like to know about"
              }
            ]
          }
        },
        {
          "planStep": {
            "parts": [
              {
                "text": " the deadlines for any other types of business entities?"
              }
            ],
            "planStepId": "123456789050",
            "role": "MODEL"
          },
          "createTime": "2025-11-24T22:21:26.070810455Z"
        }
      ]
    }
  },
  "sessionInfo": {
    "session": "projects/my-project-123/locations/global/collections/default_collection/engines/my-app/sessions/123456789013",
    "queryId": "123456789078",
    "turnId": "123456789013_123456789029"
  },
  "assistToken": "1234567890123456789012345678901234567890"
}

For more information on the fields and what is returned, see Response body.

Note: To continue the conversation in the same session, save the session value from the response and include it in your next query.

Get search results using the same session

To continue a conversation and get answers from Gemini Enterprise within an existing session, use the streamAssist method. The following code sample shows the mandatory fields:

REST

curl -X POST \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
-H "Content-Type: application/json" \
"https://ENDPOINT_LOCATION-discoveryengine.googleapis.com/v1/projects/PROJECT_ID/locations/LOCATION/collections/default_collection/engines/APP_ID/assistants/default_assistant:streamAssist" \
  -d '
{
  "session": "projects/PROJECT_ID/locations/global/collections/default_collection/engines/APP_ID/sessions/SESSION_ID",
  "query": {
    "text": "QUERY_TEXT_2"
  }
}'

Replace the following:

• ENDPOINT_LOCATION-: the multi-region for your API request. Assign one of the following values:
  • us- for the US multi-region
  • eu- for the EU multi-region
  • global- for the Global location
  For more information, see Specify a multi-region for your data store.
• PROJECT_ID: the ID of your Google Cloud project.
• APP_ID: the unique identifier for the Gemini Enterprise app.
• LOCATION: the multi-region of your data store: global, us, or eu
• QUERY_TEXT_2: the search query text.
• SESSION_ID: the ID of a session from a previous conversation or query.

Example command and result

curl -X POST \
-H "Authorization: Bearer $(gcloud auth print-access-token)" \
-H "Content-Type: application/json" \
"https://global-discoveryengine.googleapis.com/v1alpha/projects/my-project-123/locations/global/collections/default_collection/engines/my-app/assistants/default_assistant:streamAssist" \
  -d '
{
  "session": "projects/my-project-123/locations/global/collections/default_collection/engines/my-app/sessions/123456789013",
  "query": {
    "text": "what are the documents you need to file taxes?"
  }
}'

{
  "answer": {
    "name": "projects/my-project-123/locations/global/collections/default_collection/engines/my-app/sessions/123456789013/assistAnswers/15195007515750046778",
    "state": "SUCCEEDED",
    "replies": [
      {
        "groundedContent": {},
        "replyId": "123456789051"
      },
      {
        "groundedContent": {},
        "replyId": "123456789051"
      }
    ],
    "diagnosticInfo": {
      "plannerSteps": [
        {
          "queryStep": {
            "parts": [
              {
                "text": "what are the documents you need to file taxes?"
              }
            ]
          },
          "createTime": "2025-11-24T23:06:45.101296577Z"
        },
        {
          "planStep": {
            "role": "MODEL",
            "parts": [
              {
                "text": "**Identifying Tax Documents**\n"
              }
            ],
            "planStepId": "123456789051"
          },
          "createTime": "2025-11-24T23:06:48.201642404Z"
        },
        {
          "planStep": {
            "parts": [
              {
                "text": "**Formulating the Search Strategy**\n"
              }
            ],
            "role": "MODEL",
            "planStepId": "123456789051"
          },
          "createTime": "2025-11-24T23:06:51.081693248Z"
        },
        {
          "createTime": "2025-11-24T23:06:53.884827627Z",
          "planStep": {
            "parts": [
              {
                "text": "**Searching for Information**\n"
              }
            ],
            "role": "MODEL",
            "planStepId": "123456789051"
          }
        },
        {
          "createTime": "2025-11-24T23:06:55.663545003Z",
          "planStep": {
            "role": "MODEL",
            "parts": [
              {
                "text": "**Planning the Response Structure**\n"
              }
            ],
            "planStepId": "123456789051"
          }
        },
        {
          "planStep": {
            "planStepId": "123456789051",
            "parts": [
              {
                "text": "Of course, I can provide a list of the common documents and information you'll need to file your personal income taxes. Having these ready can make the process much smoother.\n\n### **Documents for Filing Personal Taxes**\n\n| Category | Document/Information | Purpose |\n| :--- | :--- | :--- |"
              }
            ],
            "role": "MODEL"
          },
          "createTime": "2025-11-24T23:06:55.687661122Z"
        },
        {
          "planStep": {
            "planStepId": "123456789051",
            "parts": [
              {
                "text": "\n| **Personal Information** | \u003cul\u003e\u003cli\u003eYour Social Security Number (SSN) or Individual Taxpayer Identification Number (ITIN)\u003c/li\u003e\u003cli\u003eSSNs or ITINs for your spouse and any dependents\u003c/li\u003e\u003c/ul\u003e | To identify you and your family members to the IRS. |\n| **Income Information** | \u003cul\u003e\u003cli\u003e**"
              }
            ],
            "role": "MODEL"
          },
          "createTime": "2025-11-24T23:06:55.713426005Z"
        },
        {
          "planStep": {
            "role": "MODEL",
            "parts": [
              {
                "text": "W-2 forms** from all employers.\u003c/li\u003e\u003cli\u003e**1099 forms** such as 1099-NEC, 1099-DIV, 1099-INT, 1099-G.\u003c/li\u003e\u003cli\u003eRecords of any other income (business, rental, etc.).\u003c/li\u003e\u003c/ul\u003e | To"
              }
            ],
            "planStepId": "123456789051"
          },
          "createTime": "2025-11-24T23:06:56.158732383Z"
        },
        {
          "createTime": "2025-11-24T23:06:56.700143436Z",
          "planStep": {
            "role": "MODEL",
            "parts": [
              {
                "text": " report all of your income from various sources. |\n| **Deductions & Credits** | \u003cul\u003e\u003cli\u003eReceipts for charitable donations.\u003c/li\u003e\u003cli\u003eMedical expense records.\u003c/li\u003e\u003cli\u003e**Form 1098** (mortgage interest) & **1098-T** (tuition).\u003c/li\u003e\u003cli\u003eChild"
              }
            ],
            "planStepId": "123456789051"
          }
        },
        {
          "planStep": {
            "planStepId": "123456789051",
            "role": "MODEL",
            "parts": [
              {
                "text": "care expense records.\u003c/li\u003e\u003c/ul\u003e | To reduce your taxable income and take advantage of tax credits. |\n| **Other Documents** | \u003cul\u003e\u003cli\u003eLast year's tax return.\u003c/li\u003e\u003cli\u003eBank account and routing numbers.\u003c/li\u003e\u003c/ul\u003e | For reference and to receive a direct deposit refund or make a payment. |\n\n---\n\nThis"
              }
            ]
          },
          "createTime": "2025-11-24T23:06:57.410549380Z"
        },
        {
          "planStep": {
            "planStepId": "123456789051",
            "parts": [
              {
                "text": " list covers the most common items, but your specific needs may vary depending on your financial situation. It's always a good idea to keep your tax-related documents organized throughout the year.\n\nIs there a specific type of income or deduction you would like to know more about?"
              }
            ],
            "role": "MODEL"
          },
          "createTime": "2025-11-24T23:06:57.960883085Z"
        }
      ]
    }
  },
  "sessionInfo": {
    "session": "projects/my-project-123/locations/global/collections/default_collection/engines/my-app/sessions/123456789013",
    "queryId": "123456789057",
    "turnId": "123456789013_123456789072"
  },
  "assistToken": "1234567890123456789012345678901234567890"
}

For more information on the fields and what is returned, see Response body.

Note: To continue the conversation in the same session, save the session value from the response and include it in your next query.