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

# What you spent

> Credits and tokens charged to your account, optionally narrowed by project,
session, or time, and optionally broken down by model, project, session, or
day.

This reports your own usage. A project you share with collaborators returns
what *you* spent on it, not the project's total — what someone else spends is
their financial data, not the project's.

Reads are eventually consistent with a live run: the engine reports usage on
an interval, so check `asOf` before treating a total as final.




## OpenAPI

````yaml /openapi/davinci-public.v2.yaml get /api/v2/usage
openapi: 3.1.0
info:
  title: Davinci Public API
  version: 2.0.0
  description: >
    Public Routing Server API contract for Davinci integrations and official
    SDKs.


    Most operations live on the canonical `/api/v2/projects` mount and accept a

    personal access token (`dav_ak_live_…` / `dav_ak_test_…`) or browser access

    token. Evaluation-run creation is the deliberate exception: it accepts only
    a

    `purpose=automation` grant issued to a running Code execution.

    Project membership and role are checked on every user call, and an API key
    is

    additionally bounded by the permission ceiling derived from its scopes — a
    key

    can never exceed what its owner can do, and usually does less.


    Collaboration operations (invitations, membership changes, ownership
    transfer)

    are deliberately absent: they require a browser session and are not part of
    the

    programmatic surface.


    ## Two planes


    Most operations are **control plane**: they run on the Routing Server, take

    small requests, and answer quickly. A few are **data plane**, marked

    `x-plane: data`, and go straight to the machine holding your project — the
    only

    practical way to move multi-gigabyte files or hold a connection open for
    half

    an hour.


    Data-plane operations use a different host and a different credential.
    Create a

    session on a project and it returns both: a `dataPlane.url` to send to and a

    short-lived `dataPlane.token` (`dav_gr_…`, a *grant*) to send with. A grant

    reaches exactly one project, carries no more permission than the key that

    minted it, expires in minutes, and dies when its session closes. It is not

    interchangeable with an API key in either direction.


    The data-plane host never names a specific machine, so a project that moves

    between machines mid-session stays reachable at the same URL.
servers:
  - url: https://davinci-app.com
    description: Production (control plane)
  - url: https://davinci-app.com/data
    description: >-
      Production (data plane). Serves the operations marked `x-plane: data`,
      using a session's grant rather than an API key.
security:
  - ApiKeyBearer: []
tags:
  - name: Projects
    description: >-
      Create, inspect, open, close, and delete projects, and manage their
      attached files.
  - name: Content
    description: >
      Read and write the objects a project is made of. These reach the running

      project rather than storage, so they see uncommitted work — and so they
      open

      the project if it is not already open.
  - name: Branches
    description: >
      Branches, commits, and the history of a single object. A commit captures
      the

      running project's state, so these operations need the branch loaded, which
      they

      arrange for the caller.
  - name: Sessions
    description: >
      A session opens a project, holds it open, and issues the grant that
      reaches the

      data plane. It is the programmatic equivalent of having a project open in
      a

      browser tab: while it lives, the project stays loaded.


      It is also where the agent lives. Send it a prompt, read its status from
      the

      session, read the transcript back, and stop a run that is going the wrong
      way.
  - name: AgentModels
    description: >
      Chat models available to your account. The returned keys are the values
      accepted

      by the session message API; availability follows your subscription,
      tenant, and

      any profile assigned to your account.
  - name: Tools
    description: >
      Invoke one of the agent's tools yourself, without the agent. Useful when
      you

      already know the operation you want and do not need a model to choose it —
      and

      when you want a deterministic result rather than an interpreted one.


      A tool is still held to the permissions of the credential invoking it, so
      a

      key cannot reach through a tool to something its scopes exclude.
  - name: Files
    description: >
      Data-plane file transfer. These reach your project's machine directly
      using a

      session's grant, which is what allows request bodies far larger than the

      control plane accepts.
  - name: Usage
    description: >
      What your models cost, broken down by model, project, session, or day.
      These

      read the usage ledger, which records one event per completed provider call
      —

      not your credit balance, which is `/api/v2/billing`.


      Usage is reported on an interval rather than per call, so a run that is
      still

      going may not be fully counted yet. Every response carries `asOf`, the
      moment

      the newest counted event was recorded, so you can see how current a total
      is

      instead of guessing.


      This is separate from `projects:read` on purpose: a key that reads your

      project data is not thereby allowed to see what you spend.
  - name: Evaluations
    description: |
      Lifecycle for the ephemeral target sandbox an evaluation runs against.
      Creation is available only to a `purpose=automation` grant issued to a
      running Code execution, so a sandbox always belongs to code rather than to
      a person's key. It returns a second, `purpose=evaluation` grant bound to
      the new sandbox; it never upgrades or replaces the source credential.
  - name: Tests
    description: >
      Asynchronously run an authored Test. The Test executes its linked Code

      object and applies its native evaluation criteria to derive the verdict.

      This is one way to start Code, not a prerequisite for anything the Code
      can

      do: the same function called directly holds the same authority.
  - name: Organizations
    description: Discover organizations available as containers for team planning.
  - name: Cards
    description: >
      Project-scoped agile cards, their index hierarchy, comments, tags,
      assignees,

      card dependencies, and design-object references. Project access is checked

      on every call; an inaccessible project is reported as not found.
  - name: Teams
    description: >
      Organization-scoped team boards, linked projects, workflow columns,
      sprints,

      analytics, and card placements. Team visibility is privacy preserving:

      inaccessible organizations, private teams, and cross-organization ids are

      reported as not found rather than revealing that they exist.
paths:
  /api/v2/usage:
    get:
      tags:
        - Usage
      summary: What you spent
      description: >
        Credits and tokens charged to your account, optionally narrowed by
        project,

        session, or time, and optionally broken down by model, project, session,
        or

        day.


        This reports your own usage. A project you share with collaborators
        returns

        what *you* spent on it, not the project's total — what someone else
        spends is

        their financial data, not the project's.


        Reads are eventually consistent with a live run: the engine reports
        usage on

        an interval, so check `asOf` before treating a total as final.
      operationId: getUsage
      parameters:
        - name: projectId
          in: query
          required: false
          description: >-
            Narrow to one project. Accepts the bare id or
            `{projectId}--{branch}`.
          schema:
            type: string
        - name: sessionId
          in: query
          required: false
          description: Narrow to one session.
          schema:
            type: string
        - $ref: '#/components/parameters/UsageFrom'
        - $ref: '#/components/parameters/UsageTo'
        - $ref: '#/components/parameters/UsageGroupBy'
      responses:
        '200':
          description: Usage totals for the scope, and the breakdown if one was asked for.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UsageResponse'
        '400':
          description: >
            Invalid request. Error code is `INVALID_GROUP_BY` or
            `INVALID_RANGE`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorEnvelope'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '429':
          $ref: '#/components/responses/RateLimited'
        '500':
          $ref: '#/components/responses/InternalError'
      security:
        - ApiKeyBearer: []
      x-codeSamples:
        - lang: typescript
          label: TypeScript SDK
          source: |
            import { DavinciClient } from '@celedon/davinci-sdk';

            const client = new DavinciClient({
              apiKey: process.env.DAVINCI_API_KEY!,
            });

            const usage = await client.usage.get({ groupBy: 'model' });
            for (const row of usage.groups ?? []) {
              console.log(row.model, row.credits);
            }
        - lang: python
          label: Python SDK
          source: |
            import os
            from davinci_sdk import DavinciClient

            with DavinciClient(api_key=os.environ["DAVINCI_API_KEY"]) as client:
                usage = client.usage.get(group_by="model")
                for row in usage.groups or []:
                    print(row.model, row.credits)
components:
  parameters:
    UsageFrom:
      name: from
      in: query
      required: false
      schema:
        type: string
        format: date-time
      description: >
        Only count events at or after this time. Omit for all of recorded
        history.
    UsageTo:
      name: to
      in: query
      required: false
      schema:
        type: string
        format: date-time
      description: Only count events at or before this time.
    UsageGroupBy:
      name: groupBy
      in: query
      required: false
      schema:
        type: string
        enum:
          - model
          - project
          - session
          - day
      description: |
        Break the totals down. Omit to receive totals only — `totals` is always
        present and always covers the whole scope, whether or not you group.
  schemas:
    UsageResponse:
      type: object
      required:
        - scope
        - asOf
        - totals
      properties:
        scope:
          type: string
          enum:
            - account
            - project
            - session
          description: What the numbers cover, determined by the path you called.
        projectId:
          type: string
          description: Present on the project and session reads. Always the bare id.
        sessionId:
          type: string
          format: uuid
          description: Present on the session read.
        asOf:
          type:
            - string
            - 'null'
          format: date-time
          description: >
            When the newest counted event was recorded, or null when the scope
            holds

            none. This is the honest bound on freshness: the engine reports
            usage on an

            interval, so a run's last few seconds may not be included. Null
            means

            "nothing here", not "nothing yet" — a scope with no usage looks the
            same

            either way, and inventing a timestamp would hide that.
        totals:
          $ref: '#/components/schemas/UsageTotals'
        groupBy:
          type: string
          enum:
            - model
            - project
            - session
            - day
          description: Echoed back when you asked for a breakdown.
        groups:
          type: array
          description: |
            One entry per group, largest spend first — except `day`, which is
            chronological. Absent unless you passed `groupBy`.
          items:
            $ref: '#/components/schemas/UsageGroup'
      additionalProperties: true
    ErrorEnvelope:
      description: >
        The error shape for every failure on this API, whether it was refused by
        the

        credential layer before reaching a domain or by the domain itself.


        Branch on `code`, which is stable. `message` is for a person reading a
        log or

        a dialog and may be reworded. `details` carries fields specific to one

        failure — a project-limit refusal reports its numbers there — and is
        absent

        when there are none.
      type: object
      required:
        - success
        - error
      properties:
        success:
          type: boolean
          const: false
        error:
          type: object
          required:
            - code
            - message
          properties:
            code:
              type: string
            message:
              type: string
            details:
              type: object
              additionalProperties: true
          additionalProperties: true
      additionalProperties: true
    UsageTotals:
      type: object
      required:
        - credits
        - promptTokens
        - completionTokens
        - reasoningTokens
        - cacheWriteTokens
        - cacheReadTokens
        - eventCount
      properties:
        credits:
          type: number
          description: Credits charged, to six decimal places.
        promptTokens:
          type: integer
        completionTokens:
          type: integer
        reasoningTokens:
          type: integer
          description: Thinking tokens, charged at the completion rate.
        cacheWriteTokens:
          type: integer
        cacheReadTokens:
          type: integer
        eventCount:
          type: integer
          description: >
            Charged calls counted. Not all of them are token-priced — image
            generation

            and web search are charged per call, so a non-zero `credits` with
            zero

            tokens is normal rather than a gap.
      additionalProperties: true
    UsageGroup:
      allOf:
        - $ref: '#/components/schemas/UsageTotals'
        - type: object
          description: >
            Totals for one group. Which identifying field is present depends on

            `groupBy`, and any of them may be null — usage with no project, for
            example

            naming a new project, is real usage that belongs to no project.
          properties:
            provider:
              type:
                - string
                - 'null'
              description: Present when grouping by model.
            model:
              type:
                - string
                - 'null'
              description: Present when grouping by model.
            projectId:
              type:
                - string
                - 'null'
              description: Present when grouping by project.
            sessionId:
              type:
                - string
                - 'null'
              description: Present when grouping by session.
            day:
              type:
                - string
                - 'null'
              format: date-time
              description: Midnight UTC of the day. Present when grouping by day.
          additionalProperties: true
  responses:
    Unauthorized:
      description: >
        No credential was supplied, or the supplied credential is malformed,
        expired,

        or revoked. A credential that is present but unusable is never
        downgraded to

        an anonymous request.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorEnvelope'
    Forbidden:
      description: >
        Authenticated but not authorized. Either the acting user lacks the
        required

        resource permission, the key's scope ceiling excludes it, or the
        endpoint

        rejects this credential type (`CREDENTIAL_NOT_PERMITTED`).
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorEnvelope'
    RateLimited:
      description: Request rate exceeded, either globally or for this key.
      headers:
        Retry-After:
          schema:
            type: integer
            minimum: 1
          description: Seconds to wait before retrying.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorEnvelope'
    InternalError:
      description: Unexpected server error.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorEnvelope'
  securitySchemes:
    ApiKeyBearer:
      type: http
      scheme: bearer
      bearerFormat: dav_ak_live_... or dav_ak_test_...
      x-default: dav_ak_live_your_token
      description: >
        Personal access token. The scopes granted at issuance determine both
        which

        operations the key may call and the ceiling on the resource permissions
        it

        can exercise. Each scope family is a ladder: `projects:manage` implies

        `projects:write` and `projects:read`; `cards:manage` implies
        `cards:write`

        and `cards:read`; and `teams:manage` implies `teams:write` and
        `teams:read`.

        These are named API capability bundles, not blanket domain roles:

        `manage` exposes only the permissions enumerated for that scope and
        never

        bypasses the acting user's current role-based access.

````