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

# Exa Answer

> Get a direct, cited answer to a question by retrieving sources and generating a grounded response.

Ask a natural-language `query` and get back a direct `answer` grounded in retrieved sources, with the supporting `citations` returned alongside it. Set `type` to control the retrieval mode used to gather sources, and set `text` to include each citation's full page body.

Supply an `outputSchema` to receive a structured answer object instead of a plain string. Billed at a flat **\$0.08** per successful request; upstream 4xx responses are not billed. For raw search results without a synthesized answer, use [`post_exa-search`](/docs/api-reference/search/post_exa-search); for deep, multi-step research use [`post_exa-agent-runs`](/docs/api-reference/search/post_exa-agent-runs).


## OpenAPI

````yaml openapi/exa.json POST /exa/answer
openapi: 3.0.0
info:
  title: Exa API
  version: 1.0.0
  description: >-
    Unified API documentation for Exa neural semantic search endpoints exposed
    through the AIsa gateway: Search, Contents, Answer, and the asynchronous
    research Agent Runs.


    Search, Contents, and Answer are synchronous and billed at a flat $0.08 per
    successful request. Agent Runs is asynchronous: the caller submits a run and
    then polls the returned job resource for status and results, billed at a
    flat $0.10 per run. Upstream 4xx responses (for example 401/403/404) are not
    billed. The `costDollars` field that Exa returns is the upstream cost
    breakdown and is informational only — customer billing follows the flat AIsa
    prices above.
servers:
  - url: https://api.aisa.one/apis/v1
security:
  - bearerAuth: []
paths:
  /exa/answer:
    post:
      tags:
        - https://docs.exa.ai/reference/answer
      summary: Get a direct, cited answer to a question.
      description: >-
        Synchronous. Retrieve relevant sources and generate a direct answer (or
        a detailed summary) with source citations. Billed at a flat $0.08 per
        successful request.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                query:
                  type: string
                  description: The question to answer.
                  example: >-
                    Which manufacturers had the top three global EV sales in
                    2025?
                text:
                  type: boolean
                  description: Include the full page text of each citation.
                type:
                  type: string
                  enum:
                    - auto
                    - fast
                    - instant
                    - deep-lite
                    - deep
                    - deep-reasoning
                  description: Retrieval mode used to gather sources before answering.
                outputSchema:
                  type: object
                  description: JSON Schema for a structured answer output.
              required:
                - query
      responses:
        '200':
          description: Answer generated successfully.
          content:
            application/json:
              schema:
                type: object
                properties:
                  requestId:
                    type: string
                  answer:
                    description: >-
                      The generated answer. A string, or a structured object
                      when outputSchema was supplied.
                    nullable: true
                  citations:
                    type: array
                    description: Sources supporting the answer.
                    items:
                      type: object
                      properties:
                        id:
                          type: string
                        url:
                          type: string
                        title:
                          type: string
                        author:
                          type: string
                        publishedDate:
                          type: string
                        text:
                          type: string
                  costDollars:
                    description: >-
                      Upstream Exa cost breakdown. Informational only; customer
                      billing is the flat $0.08.
                    nullable: true
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer

````