> ## 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.

# Ping the node

Answers from the node that serves your calls as soon as the credential is checked, and does no other work. Its time is the round trip from your client through the edge to the node and back, which is what latency targets written as "ping p50 + x" mean by the edge round trip. Any valid credential may call it, whatever its scopes. It is not metered. The response carries `Server-Timing` like every node-served call. 

` GET /v1/ping `

Ping the node

Answers from the node that serves your calls as soon as the credential is checked, and does no other work.
Its time is the round trip from your client through the edge to the node and back, which is what latency
targets written as "ping p50 + x" mean by the edge round trip. Any valid credential may call it, whatever its
scopes. It is not metered. The response carries `Server-Timing` like every node-served call.


## 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.


## Responses

### ` 200 ` — The node answered.

Content type: ` application/json `

- ` value `: type ` object `

  - Required fields: ` object `, ` node `, ` ts `

  - ` object `: type ` string `

    - enum: ` ["ping"] `

  - ` node `: type ` string ` — The id of the node that answered (`n1`).

    - example: ` "n1" `

  - ` ts `: type ` string `; format ` date-time ` — The node's clock when it answered, RFC 3339 in UTC with milliseconds.

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": "ping",
  "node": "n1",
  "ts": "2026-10-30T12:00:00.000Z"
}
```

### ` 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"
}
```

### ` 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/ping' \
  -H 'Authorization: Bearer YOUR_API_TOKEN'
```

### JavaScript

```javascript
const response = await fetch('https://beta-api.b3os.org/v1/ping', {
  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/ping', headers=headers)
print(response.json())
```