### Install the Go SDK

Source: https://sendmux.ai/docs/sdks/go

Use the go get command to add the Sendmux module to your project.

```bash
go get sendmux.ai/go@v1.0.0
```

--------------------------------

### Verify CLI Installation

Source: https://sendmux.ai/docs/cli

Check the installed version and view available commands.

```bash
sendmux --version
sendmux --help
```

--------------------------------

### Install Sendmux CLI

Source: https://sendmux.ai/docs/cli

Installation commands for Linux and macOS environments.

```bash
sudo snap install sendmux
```

```bash
brew install sendmux/tap/sendmux
```

```bash
npm install -g @sendmux/cli
```

--------------------------------

### Install Sendmux MCP package

Source: https://sendmux.ai/docs/guides/mcp

Install the required Python package from PyPI.

```bash
pip install sendmux-mcp
```

--------------------------------

### Install Sendmux SDK packages

Source: https://sendmux.ai/docs/sdks/python

Install the umbrella package for multiple surfaces or specific packages for individual API surfaces.

```bash
pip install sendmux-sdk
```

```bash
pip install sendmux-sending
```

```bash
pip install sendmux-mailbox
```

```bash
pip install sendmux-management
```

--------------------------------

### Install Sendmux Ruby SDK gems

Source: https://sendmux.ai/docs/sdks/ruby

Install the umbrella gem for multiple surfaces or individual gems for specific API access.

```bash
gem install sendmux-sdk
```

```bash
gem install sendmux-sending
```

```bash
gem install sendmux-mailbox
```

```bash
gem install sendmux-management
```

--------------------------------

### Batch get response structure

Source: https://sendmux.ai/docs/mailbox-api/introduction

Example JSON response returned by the batch-get endpoint.

```json
{
  "ok": true,
  "data": {
    "messages": [
      {
        "message": {
          "id": "msg_123",
          "thread_id": "thr_123",
          "subject": "Invoice question",
          "preview": "Can you resend the invoice?",
          "has_attachments": true
        },
        "raw_body": null,
        "content": {
          "id": "msg_123",
          "thread_id": "thr_123",
          "subject": "Invoice question",
          "body": {
            "format": "text",
            "text": "Can you resend the invoice?",
            "html": null,
            "is_truncated": false,
            "truncated_at_chars": null,
            "signature_stripped": false,
            "quotes_stripped": false,
            "extracted_links": []
          },
          "attachments": [
            {
              "id": "att_123",
              "filename": "invoice.pdf",
              "content_type": "application/pdf",
              "size_bytes": 12345,
              "disposition": "attachment",
              "content_id": null,
              "download_url": "/api/v1/mailbox/messages/msg_123/attachment-downloads/attref_abc123?download_token=..."
            }
          ]
        }
      }
    ],
    "not_found": [],
    "states": {
      "email_state": "state_token"
    }
  },
  "meta": {
    "request_id": "req_clxxxxxxxxxxxxxxxxxxxxxxxxx"
  }
}
```

--------------------------------

### Initialize API Clients

Source: https://sendmux.ai/docs/sdks/go

Create clients for Sending, Mailbox, or Management surfaces using their respective factory functions and appropriate API keys.

```go
package main

import (
	"log"
	"os"

	"sendmux.ai/go/sending"
)

func main() {
	client, err := sending.New(os.Getenv("SENDMUX_MAILBOX_API_KEY"))
	if err != nil {
		log.Fatal(err)
	}

	_ = client
}
```

```go
package main

import (
	"log"
	"os"

	"sendmux.ai/go/mailbox"
)

func main() {
	client, err := mailbox.New(os.Getenv("SENDMUX_MAILBOX_API_KEY"))
	if err != nil {
		log.Fatal(err)
	}

	_ = client
}
```

```go
package main

import (
	"log"
	"os"

	"sendmux.ai/go/management"
)

func main() {
	client, err := management.New(os.Getenv("SENDMUX_ROOT_API_KEY"))
	if err != nil {
		log.Fatal(err)
	}

	_ = client
}
```

--------------------------------

### Create API Clients

Source: https://sendmux.ai/docs/sdks/php

Initialize API clients using the factory methods provided by each package, passing the appropriate API key.

```php
<?php

require __DIR__ . '/vendor/autoload.php';

use Sendmux\Sending\ClientFactory;

$emails = ClientFactory::createEmailsApi(
    getenv('SENDMUX_MAILBOX_API_KEY') ?: ''
);
```

```php
<?php

require __DIR__ . '/vendor/autoload.php';

use Sendmux\Mailbox\ClientFactory;

$mailboxApi = ClientFactory::createMailboxAPIApi(
    getenv('SENDMUX_MAILBOX_API_KEY') ?: ''
);
```

```php
<?php

require __DIR__ . '/vendor/autoload.php';

use Sendmux\Management\ClientFactory;

$mailboxes = ClientFactory::createMailboxesApi(
    getenv('SENDMUX_ROOT_API_KEY') ?: ''
);
```

--------------------------------

### Client Initialization

Source: https://sendmux.ai/docs/sdks/go

How to initialize clients for the Sending, Mailbox, and Management surfaces using the respective factory functions.

```APIDOC
## Client Initialization

### Description
Initialize a client for a specific Sendmux API surface using the provided factory functions.

### Usage
- **Sending**: `sending.New(apiKey)`
- **Mailbox**: `mailbox.New(apiKey)`
- **Management**: `management.New(apiKey)`

### Example
```go
import "sendmux.ai/go/sending"

client, err := sending.New(os.Getenv("SENDMUX_MAILBOX_API_KEY"))
```
```

--------------------------------

### WebhookEventPayload Example

Source: https://sendmux.ai/docs/api/webhooks/get-a-webhook-delivery-payload

Example JSON structure for the webhook event payload delivered to endpoints.

```json
{
  "data": {
    "bounce_subtype": null,
    "bounce_type": null,
    "complaint_subtype": null,
    "complaint_type": null,
    "delay_expires_at": null,
    "delay_type": null,
    "is_spam": false,
    "mailbox_id": "mbx_123",
    "message_id": "ME3P282MB076951B3AAD3255D686EA8EDCA0F2@example.com",
    "message_id_kind": "rfc5322",
    "recipients": [
      "inbox@example.com"
    ],
    "reject_reason": null,
    "sender": "sender@example.com",
    "sendmux_message_id": null,
    "webhook_id": null
  },
  "id": "evt_clxxxxxxxxxxxxxxxxxxxxxxxxx",
  "occurred_at": "2026-05-21T09:12:00Z",
  "team_public_id": "team_clxxxxxxxxxxxxxxxxxxxxxxxxx",
  "type": "message.received"
}
```

--------------------------------

### Access CLI help documentation

Source: https://sendmux.ai/docs/cli

Use the --help flag on topics or specific commands to view supported flags and usage information.

```bash
sendmux sending --help
sendmux mailbox --help
sendmux management --help
sendmux sending:send --help
```

--------------------------------

### Configure Continue MCP

Source: https://sendmux.ai/docs/guides/mcp-clients

Create a YAML configuration file at .continue/mcpServers/sendmux-local.yaml.

```yaml
name: Sendmux local MCP
version: 0.0.1
schema: v1
mcpServers:
  - name: Sendmux local
    type: streamable-http
    url: http://127.0.0.1:8765/mcp
    headers:
      Authorization: Bearer local-mcp-token
```

--------------------------------

### Install Sendmux Skills in Claude Code

Source: https://sendmux.ai/docs/guides/agent-skills

Commands to add and install the Sendmux plugin within the Claude Code environment.

```text
/plugin marketplace add Sendmux/skills
/plugin install sendmux@sendmux
/reload-plugins
```

--------------------------------

### GET /providers/{public_id}

Source: https://sendmux.ai/docs/api/sending-accounts/get-a-sending-account

Returns one sending account. Responses include an ETag for conditional GET and optimistic PATCH.

```APIDOC
## GET /providers/{public_id}

### Description
Returns one sending account. Responses include an ETag for conditional GET and optimistic PATCH.

### Method
GET

### Endpoint
/providers/{public_id}

### Parameters
#### Path Parameters
- **public_id** (string) - Required - Sending account public ID

#### Header Parameters
- **If-None-Match** (string) - Optional - Weak ETag from a previous response. Returns 304 when unchanged.

### Response
#### Success Response (200)
- **data** (ProviderItem) - Sending account details

#### Success Response (304)
- Not Modified

#### Error Response (404)
- **error** (ApiError) - Sending account not found
```

--------------------------------

### Run all MCP surfaces

Source: https://sendmux.ai/docs/guides/mcp

Execute all product surfaces simultaneously by providing the necessary environment variables.

```bash
SENDMUX_MCP_SURFACES=mailbox,management,sending \
SENDMUX_MAILBOX_API_KEY=smx_mbx_... \
SENDMUX_MANAGEMENT_API_KEY=smx_root_... \
SENDMUX_SENDING_API_KEY=smx_mbx_... \
sendmux-mcp
```

--------------------------------

### Run individual MCP surfaces

Source: https://sendmux.ai/docs/guides/mcp

Execute specific product surfaces using their respective API keys.

```bash
SENDMUX_API_KEY=smx_mbx_... sendmux-mcp-mailbox
SENDMUX_API_KEY=smx_root_... sendmux-mcp-management
SENDMUX_API_KEY=smx_mbx_... sendmux-mcp-sending
```

--------------------------------

### Manage CLI Profiles

Source: https://sendmux.ai/docs/cli

List and display details for configured profiles.

```bash
sendmux profiles:list
sendmux profiles:list --verbose
sendmux profiles:show management
```

--------------------------------

### HTTP Retry-After Header Example

Source: https://sendmux.ai/docs/api/errors

Example of a 429 Too Many Requests response including the Retry-After header indicating a 30-second wait.

```http
HTTP/1.1 429 Too Many Requests
Retry-After: 30
Content-Type: application/json
```

--------------------------------

### OpenAPI definition for Get sending account limits

Source: https://sendmux.ai/docs/api/sending-accounts/get-sending-account-limits

Defines the GET /providers/limits endpoint and the associated response schemas for provider limits.

```yaml
openapi: 3.1.0
info:
  description: Programmatic access to your Sendmux email infrastructure.
  title: Sendmux API
  version: 1.0.0
servers:
  - description: API v1
    url: https://app.sendmux.ai/api/v1
security:
  - bearerAuth: []
paths:
  /providers/limits:
    get:
      tags:
        - Sending accounts
      summary: Get sending account limits
      description: >-
        Returns custom-account capacity and shared Amazon SES daily sending
        limit state.
      operationId: managementGetProviderLimits
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ProviderLimitsResponse'
          description: Limit state
      security:
        - bearerAuth: []
components:
  schemas:
    ProviderLimitsResponse:
      allOf:
        - $ref: '#/components/schemas/SuccessEnvelope'
        - properties:
            data:
              $ref: '#/components/schemas/ProviderLimits'
            meta:
              $ref: '#/components/schemas/ResponseMeta'
          required:
            - data
          type: object
      unevaluatedProperties: false
    SuccessEnvelope:
      properties:
        meta:
          additionalProperties: {}
          properties: {}
          type: object
        ok:
          enum:
            - true
          type: boolean
      required:
        - ok
        - meta
      type: object
    ProviderLimits:
      additionalProperties: false
      properties:
        sending_accounts:
          $ref: '#/components/schemas/ResourceLimitSnapshot'
        shared_amazon_ses:
          $ref: '#/components/schemas/SharedAmazonSesLimit'
      required:
        - sending_accounts
        - shared_amazon_ses
      type: object
    ResponseMeta:
      additionalProperties: false
      properties:
        request_id:
          example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
          type: string
      required:
        - request_id
      type: object
    ResourceLimitSnapshot:
      additionalProperties: false
      properties:
        can_request_increase:
          type: boolean
        is_at_limit:
          type: boolean
        is_near_limit:
          type: boolean
        max_allowed:
          exclusiveMinimum: 0
          type: integer
        pending_request_id:
          type:
            - string
            - 'null'
        reserved:
          minimum: 0
          type: integer
        resource_type:
          example: sending_accounts
          type: string
        threshold_usage:
          minimum: 0
          type: integer
        usage:
          minimum: 0
          type: integer
        usage_ratio:
          type: number
      required:
        - resource_type
        - usage
        - max_allowed
        - reserved
        - threshold_usage
        - usage_ratio
        - is_at_limit
        - is_near_limit
        - can_request_increase
        - pending_request_id
      type: object
    SharedAmazonSesLimit:
      additionalProperties: false
      properties:
        can_request_increase:
          type: boolean
        daily_limit:
          minimum: 0
          type:
            - integer
            - 'null'
        is_near_limit:
          type: boolean
        pending_request_id:
          type:
            - string
            - 'null'
        provider_id:
          type:
            - string
            - 'null'
        sent_today:
          minimum: 0
          type: integer
        threshold_usage:
          minimum: 0
          type:
            - integer
            - 'null'
        usage_ratio:
          type:
            - number
            - 'null'
      required:
        - provider_id
        - daily_limit
        - sent_today
        - threshold_usage
        - usage_ratio
        - is_near_limit
        - can_request_increase
        - pending_request_id
      type: object
  securitySchemes:
    bearerAuth:
      bearerFormat: API Key
      description: >-
        Sendmux API key. Use a root API key for Management API routes, or a
        mailbox credential for Mailbox API routes. Obtain keys from the
        dashboard under API Keys.
      scheme: bearer
      type: http
```

--------------------------------

### OpenAPI definition for Get a sending account

Source: https://sendmux.ai/docs/api/sending-accounts/get-a-sending-account

The OpenAPI specification for the GET /providers/{public_id} endpoint, including parameter definitions and response schemas.

```yaml
openapi: 3.1.0
info:
  description: Programmatic access to your Sendmux email infrastructure.
  title: Sendmux API
  version: 1.0.0
servers:
  - description: API v1
    url: https://app.sendmux.ai/api/v1
security:
  - bearerAuth: []
paths:
  /providers/{public_id}:
    get:
      tags:
        - Sending accounts
      summary: Get a sending account
      description: >-
        Returns one sending account. Responses include an ETag for conditional
        GET and optimistic PATCH.
      operationId: managementGetProvider
      parameters:
        - in: path
          name: public_id
          required: true
          schema:
            description: Sending account public ID
            example: dprov_clxxxxxxxxxxxxxxxxxxxxxxxxx
            type: string
        - in: header
          name: If-None-Match
          required: false
          schema:
            description: Weak ETag from a previous response. Returns 304 when unchanged.
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ProviderItemResponse'
          description: Sending account
          headers:
            ETag:
              description: Weak ETag.
              schema:
                example: W/"a1b2c3d4e5f60718"
                type: string
        '304':
          description: Not Modified
        '404':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Sending account not found
      security:
        - bearerAuth: []
components:
  schemas:
    ProviderItemResponse:
      allOf:
        - $ref: '#/components/schemas/SuccessEnvelope'
        - properties:
            data:
              $ref: '#/components/schemas/ProviderItem'
            meta:
              $ref: '#/components/schemas/ResponseMeta'
          required:
            - data
          type: object
      unevaluatedProperties: false
    ApiError:
      additionalProperties: false
      properties:
        error:
          additionalProperties: false
          properties:
            code:
              description: Machine-readable error code
              enum:
                - invalid_parameter
                - missing_parameter
                - authentication_required
                - insufficient_permissions
                - not_found
                - conflict
                - limit_exceeded
                - idempotency_conflict
                - payload_too_large
                - validation_error
                - rate_limit_exceeded
                - service_unavailable
                - internal_error
              example: invalid_parameter
              type: string
            doc_url:
              description: Link to relevant documentation
              type: string
            errors:
              description: >-
                Accumulated per-field issues for validation errors. Only present
                on 400/422 responses.
              items:
                $ref: '#/components/schemas/ApiErrorDetail'
              type: array
            message:
              description: Human-readable error description
              type: string
            param:
              description: The parameter that caused the error
              type: string
            retryable:
              description: >-
                Whether the caller may safely retry this request. 4xx are
                typically false (except 429); 5xx are typically true.
              example: false
              type: boolean
          required:
            - code
            - message
            - retryable
          type: object
        meta:
          additionalProperties: false
          properties:
            request_id:
              example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
              type: string
          required:
            - request_id
          type: object
        ok:
          enum:
            - false
          type: boolean
      required:
        - ok
        - error
        - meta
      type: object
    SuccessEnvelope:
      properties:
        meta:
          additionalProperties: {}
          properties: {}
          type: object
        ok:
          enum:
            - true
          type: boolean
      required:
        - ok
        - meta
      type: object
    ProviderItem:
      additionalProperties: false
      properties:
        allowed_actions:
          $ref: '#/components/schemas/ProviderAllowedActions'
        created_at:
```

--------------------------------

### Execute CLI Commands

Source: https://sendmux.ai/docs/cli

Examples of sending, mailbox, and management commands using the Sendmux CLI.

```bash
sendmux sending:send \
  --profile mailbox \
  --body '{"from":{"email":"sender@example.com"},"to":{"email":"recipient@example.com"},"subject":"Hello","text_body":"Sent with the Sendmux CLI"}' \
  --idempotency-key send-cli-001
```

```bash
sendmux mailbox:messages:list \
  --profile mailbox \
  --query limit=25
```

```bash
sendmux management:mailboxes:list \
  --profile management \
  --query limit=25
```

--------------------------------

### OpenAPI definition for Get quota changes

Source: https://sendmux.ai/docs/api/mailbox-api/get-quota-changes

Defines the GET /mailbox/quotas/changes endpoint, including parameters for sync state, pagination, and mailbox targeting.

```yaml
openapi: 3.1.0
info:
  description: Programmatic access to your Sendmux email infrastructure.
  title: Sendmux API
  version: 1.0.0
servers:
  - description: API v1
    url: https://app.sendmux.ai/api/v1
security:
  - bearerAuth: []
paths:
  /mailbox/quotas/changes:
    get:
      tags:
        - Mailbox API
      summary: Get quota changes
      description: >-
        Returns quota changes since a prior quota state, or the current quota
        state when omitted.
      operationId: mailboxGetQuotaChanges
      parameters:
        - in: query
          name: since_state
          required: false
          schema:
            type: string
        - in: query
          name: limit
          required: false
          schema:
            maximum: 500
            minimum: 1
            type: integer
        - description: >-
            Mailbox public ID to target when the credential grants access to
            more than one mailbox. Omit when the credential is scoped to exactly
            one mailbox.
          in: query
          name: mailbox_id
          required: false
          schema:
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MailboxChangesResponse'
          description: Quota changes
        '400':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Invalid sync state
      security:
        - bearerAuth: []
components:
  schemas:
    MailboxChangesResponse:
      allOf:
        - $ref: '#/components/schemas/SuccessEnvelope'
        - properties:
            data:
              $ref: '#/components/schemas/MailboxChanges'
            meta:
              $ref: '#/components/schemas/ResponseMeta'
          required:
            - data
          type: object
      unevaluatedProperties: false
    ApiError:
      additionalProperties: false
      properties:
        error:
          additionalProperties: false
          properties:
            code:
              description: Machine-readable error code
              enum:
                - invalid_parameter
                - missing_parameter
                - authentication_required
                - insufficient_permissions
                - not_found
                - conflict
                - limit_exceeded
                - idempotency_conflict
                - payload_too_large
                - validation_error
                - rate_limit_exceeded
                - service_unavailable
                - internal_error
              example: invalid_parameter
              type: string
            doc_url:
              description: Link to relevant documentation
              type: string
            errors:
              description: >-
                Accumulated per-field issues for validation errors. Only present
                on 400/422 responses.
              items:
                $ref: '#/components/schemas/ApiErrorDetail'
              type: array
            message:
              description: Human-readable error description
              type: string
            param:
              description: The parameter that caused the error
              type: string
            retryable:
              description: >-
                Whether the caller may safely retry this request. 4xx are
                typically false (except 429); 5xx are typically true.
              example: false
              type: boolean
          required:
            - code
            - message
            - retryable
          type: object
        meta:
          additionalProperties: false
          properties:
            request_id:
              example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
              type: string
          required:
            - request_id
          type: object
        ok:
          enum:
            - false
          type: boolean
      required:
        - ok
        - error
        - meta
      type: object
    SuccessEnvelope:
      properties:
        meta:
          additionalProperties: {}
          properties: {}
          type: object
        ok:
          enum:
            - true
          type: boolean
      required:
        - ok
        - meta
      type: object
    MailboxChanges:
      additionalProperties: false
      properties:
        created:
          items:
            type: string
          type: array
        destroyed:
          items:
            type: string
          type: array
        has_more:
          type: boolean
```

--------------------------------

### create_management_client

Source: https://sendmux.ai/docs/sdks/python

Initializes a client for the Management API surface.

```APIDOC
## management.create_management_client

### Description
Creates a client to interact with the Management API surface. Requires a team-scoped `smx_root_` key.

### Parameters
- **api_key** (string) - Required - The API key used for authentication.

### Example
```python
from sendmux_sdk import management
client = management.create_management_client(api_key="smx_root_...")
```
```

--------------------------------

### OpenAPI specification for Get mailbox sender identity

Source: https://sendmux.ai/docs/api/mailbox-api/get-mailbox-sender-identity

Defines the GET /mailbox/identity endpoint, including parameters, security requirements, and response schemas.

```yaml
openapi: 3.1.0
info:
  description: Programmatic access to your Sendmux email infrastructure.
  title: Sendmux API
  version: 1.0.0
servers:
  - description: API v1
    url: https://app.sendmux.ai/api/v1
security:
  - bearerAuth: []
paths:
  /mailbox/identity:
    get:
      tags:
        - Mailbox API
      summary: Get mailbox sender identity
      description: >-
        Returns the default sender identity and signatures for the authenticated
        mailbox.
      operationId: mailboxGetIdentity
      parameters:
        - description: >-
            Mailbox public ID to target when the credential grants access to
            more than one mailbox. Omit when the credential is scoped to exactly
            one mailbox.
          in: query
          name: mailbox_id
          required: false
          schema:
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MailboxIdentityResponse'
          description: Mailbox sender identity
        '401':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Authentication required
        '403':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Mailbox API key required
        '503':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Mailbox service unavailable
      security:
        - bearerAuth: []
components:
  schemas:
    MailboxIdentityResponse:
      allOf:
        - $ref: '#/components/schemas/SuccessEnvelope'
        - properties:
            data:
              $ref: '#/components/schemas/MailboxIdentity'
            meta:
              $ref: '#/components/schemas/ResponseMeta'
          required:
            - data
          type: object
      unevaluatedProperties: false
    ApiError:
      additionalProperties: false
      properties:
        error:
          additionalProperties: false
          properties:
            code:
              description: Machine-readable error code
              enum:
                - invalid_parameter
                - missing_parameter
                - authentication_required
                - insufficient_permissions
                - not_found
                - conflict
                - limit_exceeded
                - idempotency_conflict
                - payload_too_large
                - validation_error
                - rate_limit_exceeded
                - service_unavailable
                - internal_error
              example: invalid_parameter
              type: string
            doc_url:
              description: Link to relevant documentation
              type: string
            errors:
              description: >-
                Accumulated per-field issues for validation errors. Only present
                on 400/422 responses.
              items:
                $ref: '#/components/schemas/ApiErrorDetail'
              type: array
            message:
              description: Human-readable error description
              type: string
            param:
              description: The parameter that caused the error
              type: string
            retryable:
              description: >-
                Whether the caller may safely retry this request. 4xx are
                typically false (except 429); 5xx are typically true.
              example: false
              type: boolean
          required:
            - code
            - message
            - retryable
          type: object
        meta:
          additionalProperties: false
          properties:
            request_id:
              example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
              type: string
          required:
            - request_id
          type: object
        ok:
          enum:
            - false
          type: boolean
      required:
        - ok
        - error
        - meta
      type: object
    SuccessEnvelope:
      properties:
        meta:
          additionalProperties: {}
          properties: {}
          type: object
        ok:
          enum:
            - true
          type: boolean
      required:
        - ok
        - meta
      type: object
    MailboxIdentity:
      additionalProperties: false
      properties:
        bcc:
          items:
            $ref: '#/components/schemas/MailboxAddress'
          type: array
```

--------------------------------

### Configure Request Headers

Source: https://sendmux.ai/docs/sdks/go

Use surface-specific helpers to generate Idempotency-Key, If-Match, and If-None-Match headers for API operations.

```go
idempotencyKey := sending.IdempotencyKey("order-123")
ifMatch := sending.IfMatch(etag)
ifNoneMatch := sending.IfNoneMatch(etag)

_, _, _ = idempotencyKey, ifMatch, ifNoneMatch
```

--------------------------------

### Get a mailbox message OpenAPI definition

Source: https://sendmux.ai/docs/api/mailbox-api/get-a-mailbox-message

The OpenAPI specification for the GET /mailbox/messages/{message_id} endpoint, including parameter definitions and response schemas.

```yaml
openapi: 3.1.0
info:
  description: Programmatic access to your Sendmux email infrastructure.
  title: Sendmux API
  version: 1.0.0
servers:
  - description: API v1
    url: https://app.sendmux.ai/api/v1
security:
  - bearerAuth: []
paths:
  /mailbox/messages/{message_id}:
    get:
      tags:
        - Mailbox API
      summary: Get a mailbox message
      description: >-
        Returns one message from the authenticated mailbox. Responses include a
        weak `ETag` header. When attachment metadata includes short-lived
        download URLs, a conditional request may return `200` even when the
        stable message ETag matches so the response can renew expired URLs.
      operationId: mailboxGetMessage
      parameters:
        - in: path
          name: message_id
          required: true
          schema:
            description: Message ID.
            type: string
        - in: header
          name: If-None-Match
          required: false
          schema:
            description: Weak ETag from a previous response. Returns 304 when unchanged.
            type: string
        - description: >-
            Mailbox public ID to target when the credential grants access to
            more than one mailbox. Omit when the credential is scoped to exactly
            one mailbox.
          in: query
          name: mailbox_id
          required: false
          schema:
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MailboxMessageDetailResponse'
          description: Message
        '304':
          description: Not modified
        '404':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Message not found
      security:
        - bearerAuth: []
components:
  schemas:
    MailboxMessageDetailResponse:
      allOf:
        - $ref: '#/components/schemas/SuccessEnvelope'
        - properties:
            data:
              $ref: '#/components/schemas/MailboxMessage'
            meta:
              $ref: '#/components/schemas/ResponseMeta'
          required:
            - data
          type: object
      unevaluatedProperties: false
    ApiError:
      additionalProperties: false
      properties:
        error:
          additionalProperties: false
          properties:
            code:
              description: Machine-readable error code
              enum:
                - invalid_parameter
                - missing_parameter
                - authentication_required
                - insufficient_permissions
                - not_found
                - conflict
                - limit_exceeded
                - idempotency_conflict
                - payload_too_large
                - validation_error
                - rate_limit_exceeded
                - service_unavailable
                - internal_error
              example: invalid_parameter
              type: string
            doc_url:
              description: Link to relevant documentation
              type: string
            errors:
              description: >-
                Accumulated per-field issues for validation errors. Only present
                on 400/422 responses.
              items:
                $ref: '#/components/schemas/ApiErrorDetail'
              type: array
            message:
              description: Human-readable error description
              type: string
            param:
              description: The parameter that caused the error
              type: string
            retryable:
              description: >-
                Whether the caller may safely retry this request. 4xx are
                typically false (except 429); 5xx are typically true.
              example: false
              type: boolean
          required:
            - code
            - message
            - retryable
          type: object
        meta:
          additionalProperties: false
          properties:
            request_id:
              example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
              type: string
          required:
            - request_id
          type: object
        ok:
          enum:
            - false
          type: boolean
      required:
        - ok
        - error
        - meta
      type: object
    SuccessEnvelope:
```

--------------------------------

### Create Mailbox with File Input

Source: https://sendmux.ai/docs/cli

Use the --body-file flag to provide a JSON request body from a local file.

```bash
sendmux management:create-mailbox \
  --profile management \
  --body-file ./mailbox.json \
  --idempotency-key create-mailbox-001
```

--------------------------------

### OpenAPI definition for Get spend summary

Source: https://sendmux.ai/docs/api/billing/get-spend-summary

Defines the GET /billing/summary endpoint, including the optional days query parameter and the structure of the SpendSummaryResponse.

```yaml
openapi: 3.1.0
info:
  description: Programmatic access to your Sendmux email infrastructure.
  title: Sendmux API
  version: 1.0.0
servers:
  - description: API v1
    url: https://app.sendmux.ai/api/v1
security:
  - bearerAuth: []
paths:
  /billing/summary:
    get:
      tags:
        - Billing
      summary: Get spend summary
      description: Returns a spend summary over a configurable lookback period.
      operationId: managementGetSpendSummary
      parameters:
        - in: query
          name: days
          required: false
          schema:
            description: 'Lookback period in days (default: 30)'
            enum:
              - '7'
              - '30'
              - '90'
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SpendSummaryResponse'
          description: Spend summary
        '401':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Authentication required
        '403':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Insufficient permissions
      security:
        - bearerAuth: []
components:
  schemas:
    SpendSummaryResponse:
      allOf:
        - $ref: '#/components/schemas/SuccessEnvelope'
        - properties:
            data:
              $ref: '#/components/schemas/SpendSummary'
            meta:
              $ref: '#/components/schemas/ResponseMeta'
          required:
            - data
          type: object
      unevaluatedProperties: false
    ApiError:
      additionalProperties: false
      properties:
        error:
          additionalProperties: false
          properties:
            code:
              description: Machine-readable error code
              enum:
                - invalid_parameter
                - missing_parameter
                - authentication_required
                - insufficient_permissions
                - not_found
                - conflict
                - limit_exceeded
                - idempotency_conflict
                - payload_too_large
                - validation_error
                - rate_limit_exceeded
                - service_unavailable
                - internal_error
              example: invalid_parameter
              type: string
            doc_url:
              description: Link to relevant documentation
              type: string
            errors:
              description: >-
                Accumulated per-field issues for validation errors. Only present
                on 400/422 responses.
              items:
                $ref: '#/components/schemas/ApiErrorDetail'
              type: array
            message:
              description: Human-readable error description
              type: string
            param:
              description: The parameter that caused the error
              type: string
            retryable:
              description: >-
                Whether the caller may safely retry this request. 4xx are
                typically false (except 429); 5xx are typically true.
              example: false
              type: boolean
          required:
            - code
            - message
            - retryable
          type: object
        meta:
          additionalProperties: false
          properties:
            request_id:
              example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
              type: string
          required:
            - request_id
          type: object
        ok:
          enum:
            - false
          type: boolean
      required:
        - ok
        - error
        - meta
      type: object
    SuccessEnvelope:
      properties:
        meta:
          additionalProperties: {}
          properties: {}
          type: object
        ok:
          enum:
            - true
          type: boolean
      required:
        - ok
        - meta
      type: object
    SpendSummary:
      additionalProperties: false
      properties:
        currency:
          enum:
            - USD
          type: string
        period_days:
          example: 30
          type: number
        total_consumed:
          example: '54.770000'
          type: string
        total_purchased:
          example: '150.000000'
          type: string
        transaction_count:
          example: 23
          type: number
      required:
        - period_days
        - total_purchased
        - total_consumed
```

--------------------------------

### Initialize Sendmux API clients

Source: https://sendmux.ai/docs/sdks/ruby

Create clients for different API surfaces using the umbrella gem helpers.

```ruby
require 'sendmux/sdk'

client = Sendmux::SDK.sending(
  api_key: ENV.fetch('SENDMUX_MAILBOX_API_KEY')
)
```

```ruby
require 'sendmux/sdk'

client = Sendmux::SDK.mailbox(
  api_key: ENV.fetch('SENDMUX_MAILBOX_API_KEY')
)
```

```ruby
require 'sendmux/sdk'

client = Sendmux::SDK.management(
  api_key: ENV.fetch('SENDMUX_ROOT_API_KEY')
)
```

--------------------------------

### OpenAPI Specification for Get Mailbox

Source: https://sendmux.ai/docs/api/mailboxes/get-a-mailbox

Defines the GET /mailboxes/{public_id} endpoint, including path parameters, security requirements, and ETag header handling.

```yaml
openapi: 3.1.0
info:
  description: Programmatic access to your Sendmux email infrastructure.
  title: Sendmux API
  version: 1.0.0
servers:
  - description: API v1
    url: https://app.sendmux.ai/api/v1
security:
  - bearerAuth: []
paths:
  /mailboxes/{public_id}:
    get:
      tags:
        - Mailboxes
      summary: Get a mailbox
      description: >-
        Returns a single mailbox, tenant-scoped to the caller's team. Responses
        carry a weak `ETag` header — send it back as `If-None-Match` on the next
        request and the server will return `304 Not Modified` (no body) when the
        resource has not changed. The same ETag is the value to use in
        `If-Match` on PATCH for optimistic concurrency.
      operationId: managementGetMailbox
      parameters:
        - in: path
          name: public_id
          required: true
          schema:
            description: Mailbox public ID
            type: string
        - in: header
          name: If-None-Match
          required: false
          schema:
            description: Weak ETag from a previous response. Returns 304 when unchanged.
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MailboxItemResponse'
          description: Mailbox
          headers:
            ETag:
              description: >-
                Weak ETag for conditional GETs and optimistic-concurrency
                PATCHes.
              schema:
                example: W/"a1b2c3d4e5f60718"
                type: string
        '304':
          description: >-
            Not Modified — the client's cached copy (matching `If-None-Match`)
            is still current.
          headers:
            ETag:
              description: Current weak ETag (same as request's `If-None-Match`).
              schema:
                type: string
        '404':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Mailbox not found
      security:
        - bearerAuth: []
components:
  schemas:
    MailboxItemResponse:
      allOf:
        - $ref: '#/components/schemas/SuccessEnvelope'
        - properties:
            data:
              $ref: '#/components/schemas/Mailbox'
            meta:
              $ref: '#/components/schemas/ResponseMeta'
          required:
            - data
          type: object
      unevaluatedProperties: false
    ApiError:
      additionalProperties: false
      properties:
        error:
          additionalProperties: false
          properties:
            code:
              description: Machine-readable error code
              enum:
                - invalid_parameter
                - missing_parameter
                - authentication_required
                - insufficient_permissions
                - not_found
                - conflict
                - limit_exceeded
                - idempotency_conflict
                - payload_too_large
                - validation_error
                - rate_limit_exceeded
                - service_unavailable
                - internal_error
              example: invalid_parameter
              type: string
            doc_url:
              description: Link to relevant documentation
              type: string
            errors:
              description: >-
                Accumulated per-field issues for validation errors. Only present
                on 400/422 responses.
              items:
                $ref: '#/components/schemas/ApiErrorDetail'
              type: array
            message:
              description: Human-readable error description
              type: string
            param:
              description: The parameter that caused the error
              type: string
            retryable:
              description: >-
                Whether the caller may safely retry this request. 4xx are
                typically false (except 429); 5xx are typically true.
              example: false
              type: boolean
          required:
            - code
            - message
            - retryable
          type: object
        meta:
          additionalProperties: false
          properties:
            request_id:
```

--------------------------------

### Install Sendmux skills

Source: https://sendmux.ai/docs/guides/agent-access

Use this command to add the Sendmux skill pack to your agent if it supports skills.

```bash
npx skills add Sendmux/skills
```