Answer

Get an LLM answer to a question informed by Exa search results. /answer performs an Exa search and uses an LLM to generate either:

1. A direct answer for specific queries. (i.e. “What is the capital of France?” would return “Paris”)
2. A detailed summary with citations for open-ended queries (i.e. “What is the state of ai in healthcare?” would return a summary with citations to relevant sources)

The response includes both the generated answer and the sources used to create it. The endpoint also supports streaming (as stream: true), which will return tokens as they are generated.

Alternatively, you can use the OpenAI compatible chat completions interface.

cURL

cURL

curl -X POST https://api.exa.ai/answer \
  -H "x-api-key: $EXA_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"query":"<query>"}'

200

{
  "answer": "<string>",
  "requestId": "<string>",
  "citations": [
    {
      "title": "<string>",
      "url": "<string>",
      "publishedDate": "2023-11-07T05:31:56Z",
      "author": "<string>",
      "id": "<string>",
      "image": "<string>",
      "favicon": "<string>",
      "text": "<string>"
    }
  ],
  "costDollars": {
    "total": 123,
    "search": {
      "neural": 123,
      "keyword": 123
    },
    "summary": 123,
    "contents": {
      "text": 123,
      "highlights": 123,
      "summary": 123
    }
  }
}

Get your Exa API key

Create a key in the dashboard. New accounts start with free credits.

/answer supports structured output via the outputSchema parameter. Pass a JSON Schema object and the answer will be returned as structured JSON matching your schema instead of a plain string.

Authorizations

apiKeybearer

x-api-key · string · header · required

Pass your Exa API key in the x-api-key header. You can also authenticate with Authorization: Bearer .

Body

application/json

query · string · required

Natural-language question or instructions for the request.

Minimum string length: 1

stream · boolean · default: false

If true, the response is returned as a server-sent events (SSE) stream.

text · boolean · default: false

If true, returns full page text with default settings. If false, disables text return.

model · enum<string> · default: exa

The model used to generate the answer.

Available options: exa, exa-pro, exa-research, exa-fast

systemPrompt · string

Additional instructions that guide generated output or agent behavior. Use this for source preferences, novelty constraints, duplication constraints, or other behavior guidance.

userLocation · Option 1 · string Option 2 · object Option 3 · object

The end user's location, as a two-letter ISO 3166-1 country code (e.g. US) or an object with country, a latitude and longitude pair, or both. The country localizes results. Coordinates are used only for queries that name no place but depend on where the user is, such as "coffee near me". They do not set a country, so send country with them to localize results. Send only the precision your use case needs.

outputSchema · object

A JSON Schema Draft 7 specification for the desired answer structure. When provided, the answer is returned as a structured object matching the schema instead of a plain string.

Show child attributes

userIdentifier · string | null

An opaque ID your platform assigns to the end user this request is made for, such as a UUID. Lets Exa attribute usage to that end user rather than your whole team. Must not contain personal information such as an email address, phone number, username, or name. Hash such values before sending them. 1 to 64 characters: letters, digits, underscores, and hyphens. Retained even when your team has Zero Data Retention enabled. Does not affect results.

Required string length: 1 - 64

Pattern: ^[A-Za-z0-9_-]+$

Example:

"7f3a9c52-1d4e-4b8a-9e60-2c5d8a1f0b37"

Response

200

application/json

OK

answer · string object · required

The generated answer based on search results. Returns a string by default, or a structured object matching the provided outputSchema.

requestId · string

Unique identifier for the request.

citations · object[]

Search results used to generate the answer.

Show child attributes

costDollars · object

Estimated dollar cost of the request. Which fields appear depends on the endpoint.

Show child attributes