> ## Documentation Index > Fetch the complete documentation index at: https://docs.reactor.inc/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > To build and serve your own model, start at /deploy/development/quickstart and /deploy/development/overview. Deploying is the default path: reactor init scaffolds a workspace, reactor auth login authenticates, and reactor model deploy registers the model, publishes the release with the weights/ folder, and activates it on Reactor's GPUs, in one command from that workspace. Docker must be running, because the publish step builds the image locally. Bump model.version in reactor.yaml before redeploying a change, because a release that already has an image is reactivated as it is. Deployment access is granted per account, so contact team@reactor.inc if a deploy is refused. Every key in reactor.yaml is documented at /deploy/platform/reactor-yaml. Model code imports reactor_runtime; Python client code imports reactor_sdk. The runtime overview explains the model interface. Running the model on your own machine with reactor run is optional and needs a GPU you attach with --gpus; /deploy/development/local-testing covers that loop and pairs a complete brightness model with a Python client test in a separate brightness-test workspace. > Reactor hosts multiple models, each with its own connect slug (modelName) and command/event schema. The video model catalog — slug, typed SDK package, and links to its schema — is at /model-api-reference/overview. Robotics policy documentation starts at /robotics/overview; The launch policies are Cosmos Nano DROID (/robotics/cosmos/nano-policy-droid/), DreamZero DROID (/robotics/dreamzero/droid/), and FLUX Action DROID (/robotics/flux-action/droid/), organized by model family and embodiment. Some models expose one slug per experience (e.g. HappyOyster); always take the slug from the model's own pages, never guess it. > Fastest path to a working app: `npx create-reactor-app my-app --model=` scaffolds a complete app with secure auth wired up. Typed TypeScript SDKs are published as @reactor-models/; Python uses the base reactor-sdk package. > Auth: exchange an API key (rk_...) for a JWT via POST https://api.reactor.inc/tokens from your server. Never put the API key in client-side code. > Append .md to any docs URL for clean Markdown. Search these docs via the MCP server at https://docs.reactor.inc/mcp. # Get a session > Returns the session's state, its model, the tracks and commands the model declares, and, once it has ended, why. Any `developer` or `account_admin` of the account the session runs under can read it, not only the user who started it. A session on another account, or an unknown ID, answers `403`. A session token reads only the sessions bound to it. `capabilities`, `selected_transport`, and `generation` appear once the session reaches `WAITING`. `environment` and `revision` are returned only to members of the account that owns the model. `ended` appears once the session is closed. Session states: `CREATED` (accepted, being placed), `PENDING` (placed, waiting for a client), `WAITING` (offer received, answer pending), `SUSPENDED` (waiting for capacity), `ACTIVE` (a client is connected and the model is running), `INACTIVE` (the client disconnected), `CLOSED` (ended; cannot be reused). ## OpenAPI ````yaml /openapi.yaml get /sessions/{session_id} openapi: 3.1.0 info: title: Reactor Platform API version: '1' description: > The Reactor Platform API mints session tokens, starts and operates sessions, negotiates media transport, and manages your account, models, and deployments. Every path is relative to `https://api.reactor.inc`. See the [Introduction](/platform-api/introduction) and [Authentication](/platform-api/authentication) pages for credentials, versioning, and errors. contact: name: Reactor support url: https://docs.reactor.inc/resources/support servers: - url: https://api.reactor.inc description: Production security: - apiKey: [] tags: - name: Status description: >- Public, unauthenticated endpoints for service health, pricing, and the values the API accepts. - name: Tokens description: > Exchange a long-lived API key for a short-lived, session-scoped token that a client can use to create and operate sessions without holding the key. - name: Users description: > Read your own user record, your account's roster, and account memberships, and manage member roles as an account admin. - name: API Keys description: >- Revoke API keys. Use the [Dashboard](https://reactor.inc/dashboard) to list or create keys. The CLI can also create a key with `reactor auth login`. - name: Sessions description: > Create, inspect, and end sessions. A session holds one running model for one client application; media and messages flow over a transport you attach to it afterwards. - name: Transport description: > Attach a client to a session. WebRTC signaling carries ICE servers, SDP, and ICE candidates; a LiveKit room connection lets the session join a room you host. - name: Files description: > Upload files a model reads, either for one running session or ahead of time for sessions you have not started yet. - name: Recordings description: > Fetch the recorded video of a session as an HLS playlist, during the session or after it ends. - name: Accounts description: > Read and manage the account your credential acts in: its name and slug, its credit balance, its effective quotas, and its accelerator capacity. - name: Invitations description: > Invite people to your account by email, and manage pending invitations. The recipient accepts from the emailed link while signed in to the dashboard. - name: Usage description: > List the sessions your account has run, filter them by status, date, model, or API key, and read exact session totals for a date window. - name: Models description: > Register, read, update, and delete the models your account serves, and list the models you can use. The `reactor model` CLI commands are built on these endpoints. - name: Releases description: > Register a model's versioned releases, push their container image, and deploy a release with a per-region instance plan. - name: Model Weights description: > Upload and inspect the weights bundle of a release: single-request uploads, multipart uploads for large files, and the server-side finalize that marks a bundle complete. - name: Model Schemas description: > Attach an OpenAPI schema to a release that describes the model's commands, messages, and tracks. Schemas of public models are readable without credentials. - name: Model Access description: | Share a private model with other accounts, one environment at a time. - name: Projects description: > A project is the deploy identity of a model you serve on Reactor. Each model is one project, with its own UUID. Creating a project also creates its `production` environment. - name: Environments description: > An environment is a named deploy target of a project, such as `production` or `staging`. Each write to an environment creates its next revision, and the newest revision is what the environment runs. Environment access grants let another account start sessions on one environment. - name: Revisions description: > A revision is an immutable, numbered snapshot of one environment: its model image, weights, resources, instances, and variables. An environment's revisions, newest first, are its change log. - name: Images description: > Model images are the container images pushed to your model's repository, named by digest. Experimental: this API can change without notice. - name: Weight Sets description: > A weight set is a version-2 weights bundle, named by its set digest. Push the files, then put the manifest. Available when weight sets are enabled for your account. Experimental: this API can change without notice. - name: Tags description: > A tag is a movable name on one model image or one weight set of a project. A release of the model is a read-only tag. Experimental: this API can change without notice. paths: /sessions/{session_id}: parameters: - $ref: '#/components/parameters/SessionId' get: tags: - Sessions summary: Get a session description: > Returns the session's state, its model, the tracks and commands the model declares, and, once it has ended, why. Any `developer` or `account_admin` of the account the session runs under can read it, not only the user who started it. A session on another account, or an unknown ID, answers `403`. A session token reads only the sessions bound to it. `capabilities`, `selected_transport`, and `generation` appear once the session reaches `WAITING`. `environment` and `revision` are returned only to members of the account that owns the model. `ended` appears once the session is closed. Session states: `CREATED` (accepted, being placed), `PENDING` (placed, waiting for a client), `WAITING` (offer received, answer pending), `SUSPENDED` (waiting for capacity), `ACTIVE` (a client is connected and the model is running), `INACTIVE` (the client disconnected), `CLOSED` (ended; cannot be reused). operationId: getSession parameters: - $ref: '#/components/parameters/ApiVersion' responses: '200': description: The session. content: application/json: schema: $ref: '#/components/schemas/SessionDetails' examples: running: summary: A running session value: session_id: 85ded560-014c-42df-8902-89dfbca8fa00 server_info: server_version: 1.5.11 selected_transport: protocol: webrtc version: '1.0' model: name: reactor/helios version: 1.4.0 capabilities: protocol_version: '1.0' tracks: - name: main_video kind: video direction: recvonly - name: webcam kind: video direction: sendonly emission_fps: 30 generation: streamed machine_id: inst-7f9c2d state: ACTIVE cluster: 054e2495-c685-450f-9ceb-57f185b7300a zone: us-west region: us-west origin_country: US user_id: 0d7a1c4e-5b2f-4a6d-8e9c-1f3b5d7e9a2c closed: false created_at: '2026-11-04T09:30:00Z' updated_at: '2026-11-04T09:31:12Z' ended: summary: A session whose start was refused value: session_id: 85ded560-014c-42df-8902-89dfbca8fa00 model: name: reactor/fast-h3 version: 2.0.0 state: CLOSED cluster: 054e2495-c685-450f-9ceb-57f185b7300a user_id: 0d7a1c4e-5b2f-4a6d-8e9c-1f3b5d7e9a2c closed: true created_at: '2026-05-15T10:04:20Z' updated_at: '2026-05-15T10:04:31Z' ended: at: '2026-05-15T10:04:31.882Z' reason: START_REFUSED message: >- starting_input.commands[0] is refused: aspect: must be one of 16:9, 1:1, 9:16, 4:3 '400': description: '`session_id` is not a UUID.' content: application/json: schema: $ref: '#/components/schemas/Error' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' security: - apiKey: [] - sessionToken: [] components: parameters: SessionId: name: session_id in: path required: true description: The session's ID, as returned by `POST /sessions`. schema: type: string format: uuid ApiVersion: name: Reactor-API-Version in: header required: false description: >- The API protocol version the client speaks. Currently `1`. Older versions than the server's minimum get `426`. schema: type: string example: '1' schemas: SessionDetails: type: object required: - session_id - cluster - state - user_id - closed - created_at - updated_at properties: session_id: type: string format: uuid state: $ref: '#/components/schemas/SessionState' closed: type: boolean description: Whether the session has ended. model: $ref: '#/components/schemas/SessionModel' server_info: $ref: '#/components/schemas/SessionServerInfo' selected_transport: $ref: '#/components/schemas/SessionTransportProtocol' capabilities: $ref: '#/components/schemas/SessionCapabilities' generation: type: string enum: - streamed - stepped description: > The mode the model runs the session in. Appears once the session is `WAITING`, and is absent for a runtime that predates generation modes (such a session streams). cluster: type: string description: An opaque placement ID. `""` until the session is placed. zone: type: string description: The Reactor region serving the session. Omitted when unknown. region: type: string description: >- The Reactor region that served the session, such as `us-west`. Omitted when unknown. origin_country: type: string description: >- The ISO 3166-1 alpha-2 country the session was started from, when known. example: US machine_id: type: string description: >- An opaque ID of the instance serving the session. Absent until an instance picks it up. user_id: type: string format: uuid description: >- The user who started the session. Can be another member of your account. created_at: type: string format: date-time updated_at: type: string format: date-time description: The last time the session record changed. ended: $ref: '#/components/schemas/SessionEnded' environment: $ref: '#/components/schemas/SessionEnvironment' revision: $ref: '#/components/schemas/SessionRevision' Error: type: object required: - error properties: error: type: string description: >- A stable error code (for example `not_found`) on newer routes, or a sentence on older ones. When `message` is present, branch on `error`. message: type: string description: >- A human-readable explanation. Do not parse it; its wording may change. resource: type: string description: The type of the resource a `not_found` refers to. reason: type: string description: >- A more specific cause for `failed_precondition`, `aborted`, and some `invalid_request` errors. SessionState: type: string description: The session's lifecycle state. enum: - CREATED - PENDING - WAITING - SUSPENDED - ACTIVE - INACTIVE - CLOSED SessionModel: type: object properties: name: type: string description: The model name, as requested (including any environment suffix). example: reactor/helios version: type: string description: The model's version. example: 1.4.0 SessionServerInfo: type: object properties: server_version: type: string description: The Reactor API's version. example: 1.5.11 SessionTransportProtocol: type: object properties: protocol: type: string example: webrtc version: type: string description: The signaling protocol version, as `major.minor`. example: '1.0' SessionCapabilities: type: object description: What the model declares for this session, reported by its runtime. properties: protocol_version: type: string example: '1.0' tracks: type: array items: $ref: '#/components/schemas/SessionTrack' commands: type: array items: $ref: '#/components/schemas/SessionCommand' emission_fps: type: number description: The frame rate the model emits at. example: 30 SessionEnded: type: object required: - at description: Why and when the session ended. Present only once the session is closed. properties: at: type: string format: date-time description: >- When the end was recorded. Later than the moment the model stopped; do not use it to measure run time. reason: type: string description: > Why the session ended. Treat an unknown value as a reason this client does not know, not as an error. enum: - STOPPED - TIMED_OUT - MODERATED - ERROR - EVICTED - START_REFUSED - RUNTIME_RESTARTED - RUNTIME_UNREACHABLE - HEARTBEAT_LOST - USER_REQUEST - CREDIT_EXHAUSTION - MAX_DURATION_EXCEEDED - DEPLOYMENT message: type: string description: > Text from whoever `reason` names. Under `USER_REQUEST` it is the caller's own words from `DELETE`. Read `reason` before showing it. SessionEnvironment: type: object description: >- The environment the session targets. Returned only to members of the account that owns the model. properties: id: type: string format: uuid name: type: string example: staging project_id: type: string format: uuid deleted_at: type: string format: date-time description: Set when the environment was deleted after the session. SessionRevision: type: object description: >- The environment revision that served the session. Returned only to members of the account that owns the model. properties: number: type: integer example: 2 SessionTrack: type: object required: - name - kind - direction properties: mid: type: string description: The SDP media ID the track uses. Set in `track_mapping`. name: type: string description: The track's name, as the model declares it. example: main_video kind: type: string enum: - video - audio direction: type: string description: >- Direction from the client's side. `recvonly` is a track the model sends; `sendonly` is one the client sends. enum: - recvonly - sendonly - sendrecv labels: type: array items: type: string SessionCommand: type: object required: - name properties: name: type: string description: type: string schema: type: object description: The JSON Schema of the command's data. responses: Unauthorized: description: The credential is missing, invalid, or expired. content: application/json: schema: $ref: '#/components/schemas/Error' Forbidden: description: >- The credential is valid but may not perform this action, or the resource is outside the caller's permission boundary. A resource you cannot see returns `403` whether or not it exists. content: application/json: schema: $ref: '#/components/schemas/Error' securitySchemes: apiKey: type: http scheme: bearer description: >- A Reactor API key (`rk_...`), sent as `Authorization: Bearer rk_...`. Keep it on a server. sessionToken: type: http scheme: bearer bearerFormat: JWT description: >- A session-scoped JWT minted by `POST /tokens`. Accepted on `/sessions` and `/clips` only. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.