> ## Documentation Index
> Fetch the complete documentation index at: https://docs.beta.b3os.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Get a session's timeline

The session's act steps in order, one row per step (skipped steps included): kind, start, duration, status, error, the target's box in the viewport, and a JPEG thumbnail when the session was created with `thumbnails: true`. Also the cursor path: every pointer event, from act steps and from `Input.dispatchMouseEvent` commands a CDP client sent over the session's socket, with its time since the session was created. Kept with the session (at most 1,000 steps, 20,000 points and 8 MiB of thumbnails; `dropped` counts what did not fit); a row's `url` and its error's `detail` are cut to 2,048 characters, and a CDP command whose `type` or `button` is not one of the documented values adds no point. Thumbnails are dropped 15 minutes after the session closes. The closed sessions of one organization keep at most 64 MiB of timelines together: the most recently closed keep theirs, older ones read empty, with what they held counted in `dropped`. The timeline is empty for a session closed by a node restart. 

` GET /v1/vision/sessions/{session_id}/timeline `

Get a session's timeline

The session's act steps in order, one row per step (skipped steps included): kind, start, duration,
status, error, the target's box in the viewport, and a JPEG thumbnail when the session was created with
`thumbnails: true`. Also the cursor path: every pointer event, from act steps and from
`Input.dispatchMouseEvent` commands a CDP client sent over the session's socket, with its time since the
session was created. Kept with the session (at most 1,000 steps, 20,000 points and 8 MiB of thumbnails;
`dropped` counts what did not fit); a row's `url` and its error's `detail` are cut to 2,048 characters, and
a CDP command whose `type` or `button` is not one of the documented values adds no point. Thumbnails are
dropped 15 minutes after the session closes. The closed sessions of one organization keep at most 64 MiB of
timelines together: the most recently closed keep theirs, older ones read empty, with what they held
counted in `dropped`. The timeline is empty for a session closed by a node restart.


## Servers

- ` https://beta-api.b3os.org ` — API (API keys and CLI tokens)

- ` https://beta.b3os.org ` — Dashboard (session cookie and CSRF header; same paths)

## Authentication

The operation accepts these alternatives. Schemes within one alternative are required together.

### Alternative 1

- ` apiKey `: ` http `

  - HTTP scheme: ` bearer ` (b3os_sk_ API key or b3os_pat_ token)

  - `Authorization: Bearer <credential>`. Two credential kinds are accepted:

- **API keys** `b3os_sk_<32 base32>_<crc32>`, created in the dashboard or with `POST /v1/keys`. A key belongs to
  one project, has scopes, an optional spend cap and expiry, and is shown only once.
- **CLI tokens** `b3os_pat_<32 base32>_<crc32>`, issued by the device login (`b3os login`). They act for one
  user in the organization and project chosen at approval.

Keys are stored as SHA-256 hashes. The edge exchanges them for a 60-second node token before forwarding
a request to a node, so nodes never see your key.


## Parameters

### ` session_id ` (path, required)

The session ID (`brs_…`).

- ` value `: type ` string `

  - pattern: ` "^brs_[0-9a-hjkmnp-tv-z]{26}$" `

Example:

```json
"brs_01m5t3y30wcksxf22t9gwk9fwb"
```

## Responses

### ` 200 ` — The timeline.

Content type: ` application/json `

- ` value `: type ` object `

  - Required fields: ` object `, ` session_id `, ` viewport `, ` steps `, ` cursor `, ` dropped `

  - ` object `: type ` string `

    - enum: ` ["session_timeline"] `

  - ` session_id `: type ` string `

    - pattern: ` "^brs_[0-9a-hjkmnp-tv-z]{26}$" `

  - ` viewport `: type ` object ` — Browser viewport in CSS pixels.

    - Required fields: ` width `, ` height `

    - ` width `: type ` integer `

      - minimum: ` 320 `

      - maximum: ` 3840 `

    - ` height `: type ` integer `

      - minimum: ` 240 `

      - maximum: ` 2160 `

  - ` steps `: type ` array `

    - ` array item `: type ` object `

      - Required fields: ` act `, ` index `, ` kind `, ` started_at `, ` at_ms `, ` duration_ms `, ` status `, ` target `, ` url `, ` thumbnail `

      - ` act `: type ` integer ` — Which act call on the session (1, 2, ...).

        - minimum: ` 1 `

      - ` index `: type ` integer ` — The step's position in that call's `actions`.

        - minimum: ` 0 `

      - ` kind `: type ` string `

        - enum: ` ["navigate","click","hover","type","key","scroll","select","wait","evaluate","screenshot","markdown"] `

      - ` started_at `: type ` string `; format ` date-time `

      - ` at_ms `: type ` integer ` — Milliseconds from the session's creation to the step's start.

      - ` duration_ms `: type ` number `

      - ` status `: type ` string `

        - enum: ` ["ok","failed","skipped"] `

      - ` target `: type ` object `; nullable — The target's box in the viewport (CSS pixels, after it was scrolled into view), or `null` for a step without a target.

        - Title: Target box

        - Required fields: ` x `, ` y `, ` width `, ` height `

        - ` x `: type ` number `

        - ` y `: type ` number `

        - ` width `: type ` number `

        - ` height `: type ` number `

      - ` url `: type ` string `; nullable — The URL a `navigate` step reached.

      - ` error `: type ` unknown ` — The step's problem; only on a step that failed.

        - ` allOf constraint 1 `: type ` object ` — An RFC 9457 problem. `code` is stable and listed in the errors catalog; `type` links to its entry. `detail` is human-readable and may change. Extension members appear only for the codes that document them; ignore members you do not recognize. 

          - Required fields: ` type `, ` title `, ` status `, ` code `, ` detail `

          - ` type `: type ` string `; format ` uri ` — `https://docs.beta.b3os.org/errors#<code>`.

            - example: ` "https://docs.beta.b3os.org/errors#invalid_request" `

          - ` title `: type ` string ` — Short summary of the problem type.

          - ` status `: type ` integer ` — The HTTP status code, repeated for convenience.

            - minimum: ` 400 `

            - maximum: ` 599 `

          - ` code `: type ` string ` — Stable machine-readable error code from the errors catalog.

            - pattern: ` "^[a-z][a-z0-9_]*$" `

          - ` detail `: type ` string ` — Explanation of this occurrence. Never contains secrets.

          - ` instance `: type ` string ` — The request ID (`req_…`) of the request that failed. Include it when you contact support.

            - example: ` "req_01m5t4yg394wegr3j4y01qb363" `

          - ` errors `: type ` array ` — Validation problems, one per field (`invalid_request` and the other codes that list `errors`).

            - ` array item `: type ` object ` — One validation problem.

              - Required fields: ` pointer `, ` detail `

              - ` pointer `: type ` string ` — Where the problem is: a JSON pointer into the request body (`/url`, `/steps/0/uses`), or `#query/<name>`, `#path/<name>` or `#header/<name>` for parameters. 

                - example: ` "/url" `

              - ` detail `: type ` string ` — What is wrong there.

                - example: ` "must be an absolute http or https URL" `

          - ` reason `: type ` string ` — Finer-grained cause for codes that document one (`unauthorized`, `forbidden`, `egress_denied`, `upstream_unreachable`, …).

          - ` required_scope `: type ` string ` — The scope that was missing (`forbidden` with `reason: scope`).

          - ` retry_after_s `: type ` integer ` — Same value as the `Retry-After` header, for clients that only read the body.

            - minimum: ` 0 `

          - ` limit `: type ` object ` — The limit an error refers to. IDs and current values are listed by `GET /v1/limits`.

            - Required fields: ` id `, ` limit `, ` unit `

            - ` id `: type ` string ` — Limit ID, such as `vision.scrape.rpm` or `sandboxes.concurrent`.

              - example: ` "vision.scrape.rpm" `

            - ` limit `: type ` number ` — The limit's value.

            - ` unit `: type ` string ` — What the limit counts, such as `requests`, `sandboxes`, `vcpu` or `MiB`.

            - ` window_s `: type ` integer ` — Window length in seconds for rate limits and quotas.

            - ` current `: type ` number ` — Current usage against the limit, when known.

          - ` current_status `: type ` string ` — The object's current status, for state conflicts such as `sandbox_not_running`.

          - ` upstream_status `: type ` integer ` — The HTTP status the upstream returned (`upstream_error`, `action_output_invalid`).

          - ` step `: type ` string ` — The failed step, as a step ID (routines), an index (`act`) or a path such as `beats/2/do/0` (render).

          - ` pack_error `: type ` object ` — The error a pack's error mapping chose (`upstream_error` from pack actions).

            - Required fields: ` code `, ` message `, ` retryable `

            - ` code `: type ` string `

            - ` message `: type ` string `

            - ` retryable `: type ` boolean `

      - ` thumbnail `: type ` object `; nullable — A JPEG of the viewport after the step, or `null` (thumbnails off, skipped step, budget spent).

        - Title: Thumbnail

        - Required fields: ` format `, ` width `, ` height `, ` data_base64 `

        - ` format `: type ` string `

          - enum: ` ["jpeg"] `

        - ` width `: type ` integer `

          - maximum: ` 320 `

        - ` height `: type ` integer `

        - ` data_base64 `: type ` string `

  - ` cursor `: type ` array `

    - ` array item `: type ` object `

      - Required fields: ` at_ms `, ` x `, ` y `, ` type `, ` source `

      - ` at_ms `: type ` integer ` — Milliseconds from the session's creation.

      - ` x `: type ` number `

      - ` y `: type ` number `

      - ` type `: type ` string ` — `Input.dispatchMouseEvent` type: `mouseMoved`, `mousePressed`, `mouseReleased` or `mouseWheel`.

      - ` button `: type ` string ` — The button of a press or release (`left`, `middle`, `right`, `back`, `forward`).

      - ` source `: type ` string ` — `act`: an act step. `cdp`: a CDP client on the session socket.

        - enum: ` ["act","cdp"] `

  - ` dropped `: type ` object ` — What did not fit in the session's timeline.

    - Required fields: ` steps `, ` points `, ` thumbnails `

    - ` steps `: type ` integer `

    - ` points `: type ` integer `

    - ` thumbnails `: type ` integer `

Response header ` x-request-id ` — The request ID (`req_…`). It is the `instance` of any problem and the key for `GET /v1/requests/{request_id}`.

- ` value `: type ` string `

  - pattern: ` "^req_[0-9a-hjkmnp-tv-z]{26}$" `

Response header ` Server-Timing ` — Phase durations in milliseconds (W3C Server Timing); the handler's phases break the request down. For a
response whose body size is known, `total` runs from reading the request head to writing the response head.
Streaming responses (event streams, WebSockets, chunked bodies) carry no `total` here: they report their
final phases in the terminal event (`job.succeeded`, `job.failed`, `job.canceled`) or the final job. The
time from the first request byte to the last response byte is recorded in the node's metrics and request
log (`GET /v1/requests/{request_id}`). The edge prepends `edge_auth` and `edge_upstream`.


- ` value `: type ` string `

Example:

```json
{
  "object": "session_timeline",
  "session_id": "brs_01m5t3y30wcksxf22t9gwk9fwb",
  "viewport": {
    "width": 1280,
    "height": 800
  },
  "steps": [
    {
      "act": 1,
      "index": 0,
      "kind": "click",
      "started_at": "2026-10-30T18:02:11.204Z",
      "at_ms": 5120,
      "duration_ms": 3.1,
      "status": "ok",
      "target": {
        "x": 540,
        "y": 380,
        "width": 200,
        "height": 40
      },
      "url": null,
      "thumbnail": null
    }
  ],
  "cursor": [
    {
      "at_ms": 5122,
      "x": 640,
      "y": 400,
      "type": "mouseMoved",
      "source": "act"
    },
    {
      "at_ms": 5122,
      "x": 640,
      "y": 400,
      "type": "mousePressed",
      "button": "left",
      "source": "act"
    },
    {
      "at_ms": 5122,
      "x": 640,
      "y": 400,
      "type": "mouseReleased",
      "button": "left",
      "source": "act"
    }
  ],
  "dropped": {
    "steps": 0,
    "points": 0,
    "thumbnails": 0
  }
}
```

### ` 400 ` — The request failed validation (`invalid_request`, `invalid_url`).

Content type: ` application/problem+json `

- ` value `: type ` object ` — An RFC 9457 problem. `code` is stable and listed in the errors catalog; `type` links to its entry. `detail` is human-readable and may change. Extension members appear only for the codes that document them; ignore members you do not recognize. 

  - Required fields: ` type `, ` title `, ` status `, ` code `, ` detail `

  - ` type `: type ` string `; format ` uri ` — `https://docs.beta.b3os.org/errors#<code>`.

    - example: ` "https://docs.beta.b3os.org/errors#invalid_request" `

  - ` title `: type ` string ` — Short summary of the problem type.

  - ` status `: type ` integer ` — The HTTP status code, repeated for convenience.

    - minimum: ` 400 `

    - maximum: ` 599 `

  - ` code `: type ` string ` — Stable machine-readable error code from the errors catalog.

    - pattern: ` "^[a-z][a-z0-9_]*$" `

  - ` detail `: type ` string ` — Explanation of this occurrence. Never contains secrets.

  - ` instance `: type ` string ` — The request ID (`req_…`) of the request that failed. Include it when you contact support.

    - example: ` "req_01m5t4yg394wegr3j4y01qb363" `

  - ` errors `: type ` array ` — Validation problems, one per field (`invalid_request` and the other codes that list `errors`).

    - ` array item `: type ` object ` — One validation problem.

      - Required fields: ` pointer `, ` detail `

      - ` pointer `: type ` string ` — Where the problem is: a JSON pointer into the request body (`/url`, `/steps/0/uses`), or `#query/<name>`, `#path/<name>` or `#header/<name>` for parameters. 

        - example: ` "/url" `

      - ` detail `: type ` string ` — What is wrong there.

        - example: ` "must be an absolute http or https URL" `

  - ` reason `: type ` string ` — Finer-grained cause for codes that document one (`unauthorized`, `forbidden`, `egress_denied`, `upstream_unreachable`, …).

  - ` required_scope `: type ` string ` — The scope that was missing (`forbidden` with `reason: scope`).

  - ` retry_after_s `: type ` integer ` — Same value as the `Retry-After` header, for clients that only read the body.

    - minimum: ` 0 `

  - ` limit `: type ` object ` — The limit an error refers to. IDs and current values are listed by `GET /v1/limits`.

    - Required fields: ` id `, ` limit `, ` unit `

    - ` id `: type ` string ` — Limit ID, such as `vision.scrape.rpm` or `sandboxes.concurrent`.

      - example: ` "vision.scrape.rpm" `

    - ` limit `: type ` number ` — The limit's value.

    - ` unit `: type ` string ` — What the limit counts, such as `requests`, `sandboxes`, `vcpu` or `MiB`.

    - ` window_s `: type ` integer ` — Window length in seconds for rate limits and quotas.

    - ` current `: type ` number ` — Current usage against the limit, when known.

  - ` current_status `: type ` string ` — The object's current status, for state conflicts such as `sandbox_not_running`.

  - ` upstream_status `: type ` integer ` — The HTTP status the upstream returned (`upstream_error`, `action_output_invalid`).

  - ` step `: type ` string ` — The failed step, as a step ID (routines), an index (`act`) or a path such as `beats/2/do/0` (render).

  - ` pack_error `: type ` object ` — The error a pack's error mapping chose (`upstream_error` from pack actions).

    - Required fields: ` code `, ` message `, ` retryable `

    - ` code `: type ` string `

    - ` message `: type ` string `

    - ` retryable `: type ` boolean `

Response header ` x-request-id ` — The request ID (`req_…`). It is the `instance` of any problem and the key for `GET /v1/requests/{request_id}`.

- ` value `: type ` string `

  - pattern: ` "^req_[0-9a-hjkmnp-tv-z]{26}$" `

Response header ` Server-Timing ` — Phase durations in milliseconds (W3C Server Timing); the handler's phases break the request down. For a
response whose body size is known, `total` runs from reading the request head to writing the response head.
Streaming responses (event streams, WebSockets, chunked bodies) carry no `total` here: they report their
final phases in the terminal event (`job.succeeded`, `job.failed`, `job.canceled`) or the final job. The
time from the first request byte to the last response byte is recorded in the node's metrics and request
log (`GET /v1/requests/{request_id}`). The edge prepends `edge_auth` and `edge_upstream`.


- ` value `: type ` string `

Example:

```json
{
  "type": "https://docs.beta.b3os.org/errors#invalid_request",
  "title": "Invalid request",
  "status": 400,
  "code": "invalid_request",
  "detail": "1 field failed validation",
  "instance": "req_01m5t4yg394wegr3j4y01qb363",
  "errors": [
    {
      "pointer": "/url",
      "detail": "must be an absolute http or https URL"
    }
  ]
}
```

### ` 401 ` — Missing, malformed, expired or revoked credentials (`unauthorized`).

Content type: ` application/problem+json `

- ` value `: type ` object ` — An RFC 9457 problem. `code` is stable and listed in the errors catalog; `type` links to its entry. `detail` is human-readable and may change. Extension members appear only for the codes that document them; ignore members you do not recognize. 

  - Required fields: ` type `, ` title `, ` status `, ` code `, ` detail `

  - ` type `: type ` string `; format ` uri ` — `https://docs.beta.b3os.org/errors#<code>`.

    - example: ` "https://docs.beta.b3os.org/errors#invalid_request" `

  - ` title `: type ` string ` — Short summary of the problem type.

  - ` status `: type ` integer ` — The HTTP status code, repeated for convenience.

    - minimum: ` 400 `

    - maximum: ` 599 `

  - ` code `: type ` string ` — Stable machine-readable error code from the errors catalog.

    - pattern: ` "^[a-z][a-z0-9_]*$" `

  - ` detail `: type ` string ` — Explanation of this occurrence. Never contains secrets.

  - ` instance `: type ` string ` — The request ID (`req_…`) of the request that failed. Include it when you contact support.

    - example: ` "req_01m5t4yg394wegr3j4y01qb363" `

  - ` errors `: type ` array ` — Validation problems, one per field (`invalid_request` and the other codes that list `errors`).

    - ` array item `: type ` object ` — One validation problem.

      - Required fields: ` pointer `, ` detail `

      - ` pointer `: type ` string ` — Where the problem is: a JSON pointer into the request body (`/url`, `/steps/0/uses`), or `#query/<name>`, `#path/<name>` or `#header/<name>` for parameters. 

        - example: ` "/url" `

      - ` detail `: type ` string ` — What is wrong there.

        - example: ` "must be an absolute http or https URL" `

  - ` reason `: type ` string ` — Finer-grained cause for codes that document one (`unauthorized`, `forbidden`, `egress_denied`, `upstream_unreachable`, …).

  - ` required_scope `: type ` string ` — The scope that was missing (`forbidden` with `reason: scope`).

  - ` retry_after_s `: type ` integer ` — Same value as the `Retry-After` header, for clients that only read the body.

    - minimum: ` 0 `

  - ` limit `: type ` object ` — The limit an error refers to. IDs and current values are listed by `GET /v1/limits`.

    - Required fields: ` id `, ` limit `, ` unit `

    - ` id `: type ` string ` — Limit ID, such as `vision.scrape.rpm` or `sandboxes.concurrent`.

      - example: ` "vision.scrape.rpm" `

    - ` limit `: type ` number ` — The limit's value.

    - ` unit `: type ` string ` — What the limit counts, such as `requests`, `sandboxes`, `vcpu` or `MiB`.

    - ` window_s `: type ` integer ` — Window length in seconds for rate limits and quotas.

    - ` current `: type ` number ` — Current usage against the limit, when known.

  - ` current_status `: type ` string ` — The object's current status, for state conflicts such as `sandbox_not_running`.

  - ` upstream_status `: type ` integer ` — The HTTP status the upstream returned (`upstream_error`, `action_output_invalid`).

  - ` step `: type ` string ` — The failed step, as a step ID (routines), an index (`act`) or a path such as `beats/2/do/0` (render).

  - ` pack_error `: type ` object ` — The error a pack's error mapping chose (`upstream_error` from pack actions).

    - Required fields: ` code `, ` message `, ` retryable `

    - ` code `: type ` string `

    - ` message `: type ` string `

    - ` retryable `: type ` boolean `

Response header ` x-request-id ` — The request ID (`req_…`). It is the `instance` of any problem and the key for `GET /v1/requests/{request_id}`.

- ` value `: type ` string `

  - pattern: ` "^req_[0-9a-hjkmnp-tv-z]{26}$" `

Response header ` Server-Timing ` — Phase durations in milliseconds (W3C Server Timing); the handler's phases break the request down. For a
response whose body size is known, `total` runs from reading the request head to writing the response head.
Streaming responses (event streams, WebSockets, chunked bodies) carry no `total` here: they report their
final phases in the terminal event (`job.succeeded`, `job.failed`, `job.canceled`) or the final job. The
time from the first request byte to the last response byte is recorded in the node's metrics and request
log (`GET /v1/requests/{request_id}`). The edge prepends `edge_auth` and `edge_upstream`.


- ` value `: type ` string `

Example:

```json
{
  "type": "https://docs.beta.b3os.org/errors#unauthorized",
  "title": "Unauthorized",
  "status": 401,
  "code": "unauthorized",
  "detail": "API key checksum does not match; check that the whole key was copied",
  "instance": "req_01m5t4yg394wegr3j4y01qb363",
  "reason": "malformed"
}
```

### ` 403 ` — Authenticated but not allowed (`forbidden`, `egress_denied`).

Content type: ` application/problem+json `

- ` value `: type ` object ` — An RFC 9457 problem. `code` is stable and listed in the errors catalog; `type` links to its entry. `detail` is human-readable and may change. Extension members appear only for the codes that document them; ignore members you do not recognize. 

  - Required fields: ` type `, ` title `, ` status `, ` code `, ` detail `

  - ` type `: type ` string `; format ` uri ` — `https://docs.beta.b3os.org/errors#<code>`.

    - example: ` "https://docs.beta.b3os.org/errors#invalid_request" `

  - ` title `: type ` string ` — Short summary of the problem type.

  - ` status `: type ` integer ` — The HTTP status code, repeated for convenience.

    - minimum: ` 400 `

    - maximum: ` 599 `

  - ` code `: type ` string ` — Stable machine-readable error code from the errors catalog.

    - pattern: ` "^[a-z][a-z0-9_]*$" `

  - ` detail `: type ` string ` — Explanation of this occurrence. Never contains secrets.

  - ` instance `: type ` string ` — The request ID (`req_…`) of the request that failed. Include it when you contact support.

    - example: ` "req_01m5t4yg394wegr3j4y01qb363" `

  - ` errors `: type ` array ` — Validation problems, one per field (`invalid_request` and the other codes that list `errors`).

    - ` array item `: type ` object ` — One validation problem.

      - Required fields: ` pointer `, ` detail `

      - ` pointer `: type ` string ` — Where the problem is: a JSON pointer into the request body (`/url`, `/steps/0/uses`), or `#query/<name>`, `#path/<name>` or `#header/<name>` for parameters. 

        - example: ` "/url" `

      - ` detail `: type ` string ` — What is wrong there.

        - example: ` "must be an absolute http or https URL" `

  - ` reason `: type ` string ` — Finer-grained cause for codes that document one (`unauthorized`, `forbidden`, `egress_denied`, `upstream_unreachable`, …).

  - ` required_scope `: type ` string ` — The scope that was missing (`forbidden` with `reason: scope`).

  - ` retry_after_s `: type ` integer ` — Same value as the `Retry-After` header, for clients that only read the body.

    - minimum: ` 0 `

  - ` limit `: type ` object ` — The limit an error refers to. IDs and current values are listed by `GET /v1/limits`.

    - Required fields: ` id `, ` limit `, ` unit `

    - ` id `: type ` string ` — Limit ID, such as `vision.scrape.rpm` or `sandboxes.concurrent`.

      - example: ` "vision.scrape.rpm" `

    - ` limit `: type ` number ` — The limit's value.

    - ` unit `: type ` string ` — What the limit counts, such as `requests`, `sandboxes`, `vcpu` or `MiB`.

    - ` window_s `: type ` integer ` — Window length in seconds for rate limits and quotas.

    - ` current `: type ` number ` — Current usage against the limit, when known.

  - ` current_status `: type ` string ` — The object's current status, for state conflicts such as `sandbox_not_running`.

  - ` upstream_status `: type ` integer ` — The HTTP status the upstream returned (`upstream_error`, `action_output_invalid`).

  - ` step `: type ` string ` — The failed step, as a step ID (routines), an index (`act`) or a path such as `beats/2/do/0` (render).

  - ` pack_error `: type ` object ` — The error a pack's error mapping chose (`upstream_error` from pack actions).

    - Required fields: ` code `, ` message `, ` retryable `

    - ` code `: type ` string `

    - ` message `: type ` string `

    - ` retryable `: type ` boolean `

Response header ` x-request-id ` — The request ID (`req_…`). It is the `instance` of any problem and the key for `GET /v1/requests/{request_id}`.

- ` value `: type ` string `

  - pattern: ` "^req_[0-9a-hjkmnp-tv-z]{26}$" `

Response header ` Server-Timing ` — Phase durations in milliseconds (W3C Server Timing); the handler's phases break the request down. For a
response whose body size is known, `total` runs from reading the request head to writing the response head.
Streaming responses (event streams, WebSockets, chunked bodies) carry no `total` here: they report their
final phases in the terminal event (`job.succeeded`, `job.failed`, `job.canceled`) or the final job. The
time from the first request byte to the last response byte is recorded in the node's metrics and request
log (`GET /v1/requests/{request_id}`). The edge prepends `edge_auth` and `edge_upstream`.


- ` value `: type ` string `

Example:

```json
{
  "type": "https://docs.beta.b3os.org/errors#forbidden",
  "title": "Forbidden",
  "status": 403,
  "code": "forbidden",
  "detail": "This key lacks the scope sandboxes:write",
  "instance": "req_01m5t4yg394wegr3j4y01qb363",
  "reason": "scope",
  "required_scope": "sandboxes:write"
}
```

### ` 404 ` — No such browser session in this project (`session_not_found`).

Content type: ` application/problem+json `

- ` value `: type ` object ` — An RFC 9457 problem. `code` is stable and listed in the errors catalog; `type` links to its entry. `detail` is human-readable and may change. Extension members appear only for the codes that document them; ignore members you do not recognize. 

  - Required fields: ` type `, ` title `, ` status `, ` code `, ` detail `

  - ` type `: type ` string `; format ` uri ` — `https://docs.beta.b3os.org/errors#<code>`.

    - example: ` "https://docs.beta.b3os.org/errors#invalid_request" `

  - ` title `: type ` string ` — Short summary of the problem type.

  - ` status `: type ` integer ` — The HTTP status code, repeated for convenience.

    - minimum: ` 400 `

    - maximum: ` 599 `

  - ` code `: type ` string ` — Stable machine-readable error code from the errors catalog.

    - pattern: ` "^[a-z][a-z0-9_]*$" `

  - ` detail `: type ` string ` — Explanation of this occurrence. Never contains secrets.

  - ` instance `: type ` string ` — The request ID (`req_…`) of the request that failed. Include it when you contact support.

    - example: ` "req_01m5t4yg394wegr3j4y01qb363" `

  - ` errors `: type ` array ` — Validation problems, one per field (`invalid_request` and the other codes that list `errors`).

    - ` array item `: type ` object ` — One validation problem.

      - Required fields: ` pointer `, ` detail `

      - ` pointer `: type ` string ` — Where the problem is: a JSON pointer into the request body (`/url`, `/steps/0/uses`), or `#query/<name>`, `#path/<name>` or `#header/<name>` for parameters. 

        - example: ` "/url" `

      - ` detail `: type ` string ` — What is wrong there.

        - example: ` "must be an absolute http or https URL" `

  - ` reason `: type ` string ` — Finer-grained cause for codes that document one (`unauthorized`, `forbidden`, `egress_denied`, `upstream_unreachable`, …).

  - ` required_scope `: type ` string ` — The scope that was missing (`forbidden` with `reason: scope`).

  - ` retry_after_s `: type ` integer ` — Same value as the `Retry-After` header, for clients that only read the body.

    - minimum: ` 0 `

  - ` limit `: type ` object ` — The limit an error refers to. IDs and current values are listed by `GET /v1/limits`.

    - Required fields: ` id `, ` limit `, ` unit `

    - ` id `: type ` string ` — Limit ID, such as `vision.scrape.rpm` or `sandboxes.concurrent`.

      - example: ` "vision.scrape.rpm" `

    - ` limit `: type ` number ` — The limit's value.

    - ` unit `: type ` string ` — What the limit counts, such as `requests`, `sandboxes`, `vcpu` or `MiB`.

    - ` window_s `: type ` integer ` — Window length in seconds for rate limits and quotas.

    - ` current `: type ` number ` — Current usage against the limit, when known.

  - ` current_status `: type ` string ` — The object's current status, for state conflicts such as `sandbox_not_running`.

  - ` upstream_status `: type ` integer ` — The HTTP status the upstream returned (`upstream_error`, `action_output_invalid`).

  - ` step `: type ` string ` — The failed step, as a step ID (routines), an index (`act`) or a path such as `beats/2/do/0` (render).

  - ` pack_error `: type ` object ` — The error a pack's error mapping chose (`upstream_error` from pack actions).

    - Required fields: ` code `, ` message `, ` retryable `

    - ` code `: type ` string `

    - ` message `: type ` string `

    - ` retryable `: type ` boolean `

Response header ` x-request-id ` — The request ID (`req_…`). It is the `instance` of any problem and the key for `GET /v1/requests/{request_id}`.

- ` value `: type ` string `

  - pattern: ` "^req_[0-9a-hjkmnp-tv-z]{26}$" `

Response header ` Server-Timing ` — Phase durations in milliseconds (W3C Server Timing); the handler's phases break the request down. For a
response whose body size is known, `total` runs from reading the request head to writing the response head.
Streaming responses (event streams, WebSockets, chunked bodies) carry no `total` here: they report their
final phases in the terminal event (`job.succeeded`, `job.failed`, `job.canceled`) or the final job. The
time from the first request byte to the last response byte is recorded in the node's metrics and request
log (`GET /v1/requests/{request_id}`). The edge prepends `edge_auth` and `edge_upstream`.


- ` value `: type ` string `

Example:

```json
{
  "type": "https://docs.beta.b3os.org/errors#session_not_found",
  "title": "Browser session not found",
  "status": 404,
  "code": "session_not_found",
  "detail": "No browser session brs_01m5t3y30wcksxf22t9gwk9fwb in this project",
  "instance": "req_01m5t4yg394wegr3j4y01qb363"
}
```

### ` 429 ` — A rate, concurrency or quota limit applies (`rate_limited`, `concurrency_limited`, `quota_exceeded`).

Content type: ` application/problem+json `

- ` value `: type ` object ` — An RFC 9457 problem. `code` is stable and listed in the errors catalog; `type` links to its entry. `detail` is human-readable and may change. Extension members appear only for the codes that document them; ignore members you do not recognize. 

  - Required fields: ` type `, ` title `, ` status `, ` code `, ` detail `

  - ` type `: type ` string `; format ` uri ` — `https://docs.beta.b3os.org/errors#<code>`.

    - example: ` "https://docs.beta.b3os.org/errors#invalid_request" `

  - ` title `: type ` string ` — Short summary of the problem type.

  - ` status `: type ` integer ` — The HTTP status code, repeated for convenience.

    - minimum: ` 400 `

    - maximum: ` 599 `

  - ` code `: type ` string ` — Stable machine-readable error code from the errors catalog.

    - pattern: ` "^[a-z][a-z0-9_]*$" `

  - ` detail `: type ` string ` — Explanation of this occurrence. Never contains secrets.

  - ` instance `: type ` string ` — The request ID (`req_…`) of the request that failed. Include it when you contact support.

    - example: ` "req_01m5t4yg394wegr3j4y01qb363" `

  - ` errors `: type ` array ` — Validation problems, one per field (`invalid_request` and the other codes that list `errors`).

    - ` array item `: type ` object ` — One validation problem.

      - Required fields: ` pointer `, ` detail `

      - ` pointer `: type ` string ` — Where the problem is: a JSON pointer into the request body (`/url`, `/steps/0/uses`), or `#query/<name>`, `#path/<name>` or `#header/<name>` for parameters. 

        - example: ` "/url" `

      - ` detail `: type ` string ` — What is wrong there.

        - example: ` "must be an absolute http or https URL" `

  - ` reason `: type ` string ` — Finer-grained cause for codes that document one (`unauthorized`, `forbidden`, `egress_denied`, `upstream_unreachable`, …).

  - ` required_scope `: type ` string ` — The scope that was missing (`forbidden` with `reason: scope`).

  - ` retry_after_s `: type ` integer ` — Same value as the `Retry-After` header, for clients that only read the body.

    - minimum: ` 0 `

  - ` limit `: type ` object ` — The limit an error refers to. IDs and current values are listed by `GET /v1/limits`.

    - Required fields: ` id `, ` limit `, ` unit `

    - ` id `: type ` string ` — Limit ID, such as `vision.scrape.rpm` or `sandboxes.concurrent`.

      - example: ` "vision.scrape.rpm" `

    - ` limit `: type ` number ` — The limit's value.

    - ` unit `: type ` string ` — What the limit counts, such as `requests`, `sandboxes`, `vcpu` or `MiB`.

    - ` window_s `: type ` integer ` — Window length in seconds for rate limits and quotas.

    - ` current `: type ` number ` — Current usage against the limit, when known.

  - ` current_status `: type ` string ` — The object's current status, for state conflicts such as `sandbox_not_running`.

  - ` upstream_status `: type ` integer ` — The HTTP status the upstream returned (`upstream_error`, `action_output_invalid`).

  - ` step `: type ` string ` — The failed step, as a step ID (routines), an index (`act`) or a path such as `beats/2/do/0` (render).

  - ` pack_error `: type ` object ` — The error a pack's error mapping chose (`upstream_error` from pack actions).

    - Required fields: ` code `, ` message `, ` retryable `

    - ` code `: type ` string `

    - ` message `: type ` string `

    - ` retryable `: type ` boolean `

Response header ` x-request-id ` — The request ID (`req_…`). It is the `instance` of any problem and the key for `GET /v1/requests/{request_id}`.

- ` value `: type ` string `

  - pattern: ` "^req_[0-9a-hjkmnp-tv-z]{26}$" `

Response header ` Server-Timing ` — Phase durations in milliseconds (W3C Server Timing); the handler's phases break the request down. For a
response whose body size is known, `total` runs from reading the request head to writing the response head.
Streaming responses (event streams, WebSockets, chunked bodies) carry no `total` here: they report their
final phases in the terminal event (`job.succeeded`, `job.failed`, `job.canceled`) or the final job. The
time from the first request byte to the last response byte is recorded in the node's metrics and request
log (`GET /v1/requests/{request_id}`). The edge prepends `edge_auth` and `edge_upstream`.


- ` value `: type ` string `

Response header ` Retry-After ` — Seconds to wait before retrying or polling again.

- ` value `: type ` integer `

  - minimum: ` 0 `

Response header ` RateLimit-Limit ` — Requests allowed in the current window for the limit that applies to this operation.

- ` value `: type ` integer `

Response header ` RateLimit-Remaining ` — Requests left in the current window.

- ` value `: type ` integer `

Response header ` RateLimit-Reset ` — Seconds until the current window resets.

- ` value `: type ` integer `

Response header ` RateLimit-Policy ` — The applied policy as `<limit>;w=<window seconds>;name="<limit id>"` (limit IDs are listed by `GET /v1/limits`).

- ` value `: type ` string `

Example:

```json
{
  "type": "https://docs.beta.b3os.org/errors#rate_limited",
  "title": "Rate limited",
  "status": 429,
  "code": "rate_limited",
  "detail": "60 scrapes per minute allowed; retry in 12 seconds",
  "instance": "req_01m5t4yg394wegr3j4y01qb363",
  "retry_after_s": 12,
  "limit": {
    "id": "vision.scrape.rpm",
    "limit": 60,
    "unit": "requests",
    "window_s": 60,
    "current": 60
  }
}
```

### ` 500 ` — Something failed inside B3OS (`internal`). Retry with backoff.

Content type: ` application/problem+json `

- ` value `: type ` object ` — An RFC 9457 problem. `code` is stable and listed in the errors catalog; `type` links to its entry. `detail` is human-readable and may change. Extension members appear only for the codes that document them; ignore members you do not recognize. 

  - Required fields: ` type `, ` title `, ` status `, ` code `, ` detail `

  - ` type `: type ` string `; format ` uri ` — `https://docs.beta.b3os.org/errors#<code>`.

    - example: ` "https://docs.beta.b3os.org/errors#invalid_request" `

  - ` title `: type ` string ` — Short summary of the problem type.

  - ` status `: type ` integer ` — The HTTP status code, repeated for convenience.

    - minimum: ` 400 `

    - maximum: ` 599 `

  - ` code `: type ` string ` — Stable machine-readable error code from the errors catalog.

    - pattern: ` "^[a-z][a-z0-9_]*$" `

  - ` detail `: type ` string ` — Explanation of this occurrence. Never contains secrets.

  - ` instance `: type ` string ` — The request ID (`req_…`) of the request that failed. Include it when you contact support.

    - example: ` "req_01m5t4yg394wegr3j4y01qb363" `

  - ` errors `: type ` array ` — Validation problems, one per field (`invalid_request` and the other codes that list `errors`).

    - ` array item `: type ` object ` — One validation problem.

      - Required fields: ` pointer `, ` detail `

      - ` pointer `: type ` string ` — Where the problem is: a JSON pointer into the request body (`/url`, `/steps/0/uses`), or `#query/<name>`, `#path/<name>` or `#header/<name>` for parameters. 

        - example: ` "/url" `

      - ` detail `: type ` string ` — What is wrong there.

        - example: ` "must be an absolute http or https URL" `

  - ` reason `: type ` string ` — Finer-grained cause for codes that document one (`unauthorized`, `forbidden`, `egress_denied`, `upstream_unreachable`, …).

  - ` required_scope `: type ` string ` — The scope that was missing (`forbidden` with `reason: scope`).

  - ` retry_after_s `: type ` integer ` — Same value as the `Retry-After` header, for clients that only read the body.

    - minimum: ` 0 `

  - ` limit `: type ` object ` — The limit an error refers to. IDs and current values are listed by `GET /v1/limits`.

    - Required fields: ` id `, ` limit `, ` unit `

    - ` id `: type ` string ` — Limit ID, such as `vision.scrape.rpm` or `sandboxes.concurrent`.

      - example: ` "vision.scrape.rpm" `

    - ` limit `: type ` number ` — The limit's value.

    - ` unit `: type ` string ` — What the limit counts, such as `requests`, `sandboxes`, `vcpu` or `MiB`.

    - ` window_s `: type ` integer ` — Window length in seconds for rate limits and quotas.

    - ` current `: type ` number ` — Current usage against the limit, when known.

  - ` current_status `: type ` string ` — The object's current status, for state conflicts such as `sandbox_not_running`.

  - ` upstream_status `: type ` integer ` — The HTTP status the upstream returned (`upstream_error`, `action_output_invalid`).

  - ` step `: type ` string ` — The failed step, as a step ID (routines), an index (`act`) or a path such as `beats/2/do/0` (render).

  - ` pack_error `: type ` object ` — The error a pack's error mapping chose (`upstream_error` from pack actions).

    - Required fields: ` code `, ` message `, ` retryable `

    - ` code `: type ` string `

    - ` message `: type ` string `

    - ` retryable `: type ` boolean `

Response header ` x-request-id ` — The request ID (`req_…`). It is the `instance` of any problem and the key for `GET /v1/requests/{request_id}`.

- ` value `: type ` string `

  - pattern: ` "^req_[0-9a-hjkmnp-tv-z]{26}$" `

Response header ` Server-Timing ` — Phase durations in milliseconds (W3C Server Timing); the handler's phases break the request down. For a
response whose body size is known, `total` runs from reading the request head to writing the response head.
Streaming responses (event streams, WebSockets, chunked bodies) carry no `total` here: they report their
final phases in the terminal event (`job.succeeded`, `job.failed`, `job.canceled`) or the final job. The
time from the first request byte to the last response byte is recorded in the node's metrics and request
log (`GET /v1/requests/{request_id}`). The edge prepends `edge_auth` and `edge_upstream`.


- ` value `: type ` string `

Example:

```json
{
  "type": "https://docs.beta.b3os.org/errors#internal",
  "title": "Internal error",
  "status": 500,
  "code": "internal",
  "detail": "internal error",
  "instance": "req_01m5t4yg394wegr3j4y01qb363"
}
```

### ` 503 ` — The node or the product is not available right now (`node_unavailable`, `product_unavailable`, `capacity_unavailable`).

Content type: ` application/problem+json `

- ` value `: type ` object ` — An RFC 9457 problem. `code` is stable and listed in the errors catalog; `type` links to its entry. `detail` is human-readable and may change. Extension members appear only for the codes that document them; ignore members you do not recognize. 

  - Required fields: ` type `, ` title `, ` status `, ` code `, ` detail `

  - ` type `: type ` string `; format ` uri ` — `https://docs.beta.b3os.org/errors#<code>`.

    - example: ` "https://docs.beta.b3os.org/errors#invalid_request" `

  - ` title `: type ` string ` — Short summary of the problem type.

  - ` status `: type ` integer ` — The HTTP status code, repeated for convenience.

    - minimum: ` 400 `

    - maximum: ` 599 `

  - ` code `: type ` string ` — Stable machine-readable error code from the errors catalog.

    - pattern: ` "^[a-z][a-z0-9_]*$" `

  - ` detail `: type ` string ` — Explanation of this occurrence. Never contains secrets.

  - ` instance `: type ` string ` — The request ID (`req_…`) of the request that failed. Include it when you contact support.

    - example: ` "req_01m5t4yg394wegr3j4y01qb363" `

  - ` errors `: type ` array ` — Validation problems, one per field (`invalid_request` and the other codes that list `errors`).

    - ` array item `: type ` object ` — One validation problem.

      - Required fields: ` pointer `, ` detail `

      - ` pointer `: type ` string ` — Where the problem is: a JSON pointer into the request body (`/url`, `/steps/0/uses`), or `#query/<name>`, `#path/<name>` or `#header/<name>` for parameters. 

        - example: ` "/url" `

      - ` detail `: type ` string ` — What is wrong there.

        - example: ` "must be an absolute http or https URL" `

  - ` reason `: type ` string ` — Finer-grained cause for codes that document one (`unauthorized`, `forbidden`, `egress_denied`, `upstream_unreachable`, …).

  - ` required_scope `: type ` string ` — The scope that was missing (`forbidden` with `reason: scope`).

  - ` retry_after_s `: type ` integer ` — Same value as the `Retry-After` header, for clients that only read the body.

    - minimum: ` 0 `

  - ` limit `: type ` object ` — The limit an error refers to. IDs and current values are listed by `GET /v1/limits`.

    - Required fields: ` id `, ` limit `, ` unit `

    - ` id `: type ` string ` — Limit ID, such as `vision.scrape.rpm` or `sandboxes.concurrent`.

      - example: ` "vision.scrape.rpm" `

    - ` limit `: type ` number ` — The limit's value.

    - ` unit `: type ` string ` — What the limit counts, such as `requests`, `sandboxes`, `vcpu` or `MiB`.

    - ` window_s `: type ` integer ` — Window length in seconds for rate limits and quotas.

    - ` current `: type ` number ` — Current usage against the limit, when known.

  - ` current_status `: type ` string ` — The object's current status, for state conflicts such as `sandbox_not_running`.

  - ` upstream_status `: type ` integer ` — The HTTP status the upstream returned (`upstream_error`, `action_output_invalid`).

  - ` step `: type ` string ` — The failed step, as a step ID (routines), an index (`act`) or a path such as `beats/2/do/0` (render).

  - ` pack_error `: type ` object ` — The error a pack's error mapping chose (`upstream_error` from pack actions).

    - Required fields: ` code `, ` message `, ` retryable `

    - ` code `: type ` string `

    - ` message `: type ` string `

    - ` retryable `: type ` boolean `

Response header ` x-request-id ` — The request ID (`req_…`). It is the `instance` of any problem and the key for `GET /v1/requests/{request_id}`.

- ` value `: type ` string `

  - pattern: ` "^req_[0-9a-hjkmnp-tv-z]{26}$" `

Response header ` Server-Timing ` — Phase durations in milliseconds (W3C Server Timing); the handler's phases break the request down. For a
response whose body size is known, `total` runs from reading the request head to writing the response head.
Streaming responses (event streams, WebSockets, chunked bodies) carry no `total` here: they report their
final phases in the terminal event (`job.succeeded`, `job.failed`, `job.canceled`) or the final job. The
time from the first request byte to the last response byte is recorded in the node's metrics and request
log (`GET /v1/requests/{request_id}`). The edge prepends `edge_auth` and `edge_upstream`.


- ` value `: type ` string `

Response header ` Retry-After ` — Seconds to wait before retrying or polling again.

- ` value `: type ` integer `

  - minimum: ` 0 `

Example:

```json
{
  "type": "https://docs.beta.b3os.org/errors#node_unavailable",
  "title": "Node unavailable",
  "status": 503,
  "code": "node_unavailable",
  "detail": "Node n1 is not reachable; retry in 5 seconds",
  "instance": "req_01m5t4yg394wegr3j4y01qb363",
  "retry_after_s": 5
}
```

## Request examples

### cURL

```curl
curl -X GET 'https://beta-api.b3os.org/v1/vision/sessions/brs_01m5t3y30wcksxf22t9gwk9fwb/timeline' \
  -H 'Authorization: Bearer YOUR_API_TOKEN'
```

### JavaScript

```javascript
const response = await fetch('https://beta-api.b3os.org/v1/vision/sessions/brs_01m5t3y30wcksxf22t9gwk9fwb/timeline', {
  method: 'GET',
  headers: {
      "Authorization": "Bearer YOUR_API_TOKEN"
  }
});

const data = await response.json();
console.log(data);
```

### Python

```python
import requests

headers = {
    'Authorization': 'Bearer YOUR_API_TOKEN'
}

response = requests.get('https://beta-api.b3os.org/v1/vision/sessions/brs_01m5t3y30wcksxf22t9gwk9fwb/timeline', headers=headers)
print(response.json())
```