> ## 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 on one project > The same reading as `getUsage`, scoped to one project and authorized against it — you must be able to read the project as well as hold `usage:read`. Usage is recorded against the bare project id, so this covers every branch of the project rather than only the one you name. ## OpenAPI ````yaml /openapi/davinci-public.v2.yaml get /api/v2/projects/{projectId}/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/projects/{projectId}/usage: parameters: - $ref: '#/components/parameters/ProjectId' get: tags: - Usage summary: What you spent on one project description: > The same reading as `getUsage`, scoped to one project and authorized against it — you must be able to read the project as well as hold `usage:read`. Usage is recorded against the bare project id, so this covers every branch of the project rather than only the one you name. operationId: getProjectUsage parameters: - $ref: '#/components/parameters/UsageFrom' - $ref: '#/components/parameters/UsageTo' - $ref: '#/components/parameters/UsageGroupBy' responses: '200': description: Usage totals for the project. 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' '404': $ref: '#/components/responses/NotFound' '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.forProject(projectId, { groupBy: 'day' }); console.log(usage.totals.credits, usage.asOf); - 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.for_project(project_id, group_by="day") print(usage.totals.credits, usage.as_of) components: parameters: ProjectId: name: projectId in: path required: true schema: type: string minLength: 1 description: Project id. May be compound in the form `{projectId}--{branchName}`. 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' NotFound: description: > The resource does not exist in the parent named by the path, or is hidden from the caller. Absence and privacy denial are deliberately indistinguishable so project, organization, and private-team existence cannot be probed. 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. ````