> ## Documentation Index > Fetch the complete documentation index at: https://sendmux.ai/docs/llms.txt > Use this file to discover all available pages before exploring further. # Read attachment text > Read or poll a requested extraction. Returns 404 after cache expiry or source removal. Current access and source availability are checked even with If-None-Match. This request does not start a conversion. ## OpenAPI ````yaml /openapi-app.json get /mailbox/messages/{message_id}/attachments/{attachment_id}/text 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: [] - oauth2: [] paths: /mailbox/messages/{message_id}/attachments/{attachment_id}/text: get: tags: - Mailbox API summary: Read attachment text description: >- Read or poll a requested extraction. Returns 404 after cache expiry or source removal. Current access and source availability are checked even with If-None-Match. This request does not start a conversion. operationId: mailboxGetAttachmentText parameters: - description: Message ID in the selected mailbox. in: path name: message_id required: true schema: description: Message ID in the selected mailbox. type: string - description: Attachment ID from that message. in: path name: attachment_id required: true schema: description: Attachment ID from that message. type: string - description: >- Maximum UTF-8 text bytes returned. Default 262144; maximum 1048576. Applies to cached results too. in: query name: max_bytes required: false schema: description: >- Maximum UTF-8 text bytes returned. Default 262144; maximum 1048576. Applies to cached results too. maximum: 1048576 minimum: 1 type: integer - description: Return 304 when the authorised response is unchanged. in: header name: If-None-Match required: false schema: description: Return 304 when the authorised response is 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: examples: ready: value: data: expires_at: '2026-09-30T00:00:00.000Z' format: markdown id: ext_example outcome: ready status: complete text: |- # Invoice Amount: $25 truncated: false meta: request_id: req_example ok: true unsupported: value: data: expires_at: '2026-09-30T00:00:00.000Z' format: markdown id: ext_example outcome: unsupported status: complete text: '' truncated: false meta: request_id: req_example ok: true schema: $ref: '#/components/schemas/MailboxAttachmentTextResponse' description: >- Conversion completed. Check outcome before using text; original attachment downloads remain available. headers: ETag: description: Current response validator, returned by GET. schema: type: string '202': content: application/json: example: data: expires_at: '2026-09-30T00:00:00.000Z' format: markdown id: ext_example outcome: null status: pending text: null truncated: false meta: request_id: req_example ok: true schema: $ref: '#/components/schemas/MailboxAttachmentTextResponse' description: Extraction is pending or running. Poll GET on this same URL. headers: ETag: description: Current response validator, returned by GET. schema: type: string '304': description: Extraction response has not changed. headers: ETag: description: Current response validator, returned by GET. schema: type: string '400': content: application/json: schema: $ref: '#/components/schemas/ApiError' description: Request could not be completed. '401': content: application/json: schema: $ref: '#/components/schemas/ApiError' description: Request could not be completed. '403': content: application/json: schema: $ref: '#/components/schemas/ApiError' description: Request could not be completed. '404': content: application/json: schema: $ref: '#/components/schemas/ApiError' description: Source attachment or unexpired extraction not found. '429': content: application/json: schema: $ref: '#/components/schemas/ApiError' description: Request could not be completed. '500': content: application/json: schema: $ref: '#/components/schemas/ApiError' description: Request could not be completed. '503': content: application/json: schema: $ref: '#/components/schemas/ApiError' description: Request could not be completed. security: - bearerAuth: [] - oauth2: - mailbox.read components: schemas: MailboxAttachmentTextResponse: allOf: - $ref: '#/components/schemas/SuccessEnvelope' - properties: data: $ref: '#/components/schemas/MailboxAttachmentText' 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 MailboxAttachmentText: additionalProperties: false properties: expires_at: description: Cache expiry. A new POST is needed after expiry. format: date-time type: string format: description: Extracted text format. enum: - markdown type: string id: description: Extraction ID. example: ext_example type: string outcome: anyOf: - enum: - ready - unsupported - encrypted - malformed - ocr_required - resource_limit - source_unavailable - failed type: string - type: 'null' description: >- Null while pending or running. Only ready contains extracted text; other outcomes contain an empty string. status: description: Poll until complete to read the outcome. enum: - pending - running - complete type: string text: description: >- Markdown text, or null until complete. Limited to max_bytes in UTF-8. type: - string - 'null' truncated: description: True when conversion or the requested output bound omitted text. type: boolean required: - id - status - outcome - text - format - truncated - expires_at type: object ResponseMeta: additionalProperties: false properties: request_id: example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx type: string required: - request_id type: object ApiErrorDetail: additionalProperties: false properties: code: description: >- Machine-readable issue code from the validator (e.g. zod issue code). example: invalid_string type: string field: description: Dot-path of the offending request field. example: recipient.email type: string message: description: Human-readable issue description. type: string required: - field - code - message 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 oauth2: description: >- Use the authorisation-code flow with S256 PKCE and resource=https://sendmux.ai/api. The user selects the team, API access and mailboxes during consent. OAuth access tokens authenticate HTTP API requests; use separate credentials for SMTP and IMAP. flows: authorizationCode: authorizationUrl: https://app.sendmux.ai/oauth/authorize refreshUrl: https://app.sendmux.ai/oauth/token scopes: analytics.*: All analytics operations analytics.read: View key usage analytics and verification logs billing.*: All billing operations billing.auto_topup: Configure auto top-up settings billing.read: View balance, transactions, invoices billing.topup: Purchase balance top-ups domain.*: All domain operations domain.create: Add sending domains domain.delete: Remove domains domain.read: List/view domains and DNS status domain.verify: Trigger domain verification email.receive: Authorise email reception email.send: Send email through the HTTP API key.*: All key management operations key.create: Create new API keys (both root and mailbox) key.read: List/view API keys and their metadata key.revoke: Revoke API keys key.rotate: Rotate API keys logs.*: All log operations logs.read: View delivery logs mailbox.admin.*: All mailbox admin operations mailbox.admin.create: Create mailboxes (admin-level) mailbox.admin.delete: Delete mailboxes (admin-level) mailbox.admin.manage: Manage all mailbox settings mailbox.admin.read: List/view mailboxes (admin-level) mailbox.drafts.write: Create and edit saved mailbox drafts mailbox.read: Read mailbox contents (folders, messages) mailbox.settings.update: Update own mailbox settings (signature, auto-reply) provider.*: All provider operations provider.create: Add email provider accounts (Google, Microsoft, SMTP) provider.delete: Remove provider accounts provider.read: List/view provider accounts and connection status provider.update: Update provider settings, refresh tokens routing.*: All routing operations routing.create: Create delivery groups routing.delete: Remove delivery groups routing.read: List/view delivery groups and routing rules routing.update: Update delivery group configuration team.*: All team operations team.members.invite: Invite team members team.members.remove: Remove team members team.members.roles: Change member roles team.read: View team settings and members team.update: Update team settings webhook.*: All webhook operations webhook.create: Create webhook subscriptions webhook.delete: Delete webhook subscriptions webhook.manage: Rotate signing secret + send test events webhook.read: List/view webhook subscriptions webhook.update: Update webhook URL, event types, enabled flag tokenUrl: https://app.sendmux.ai/oauth/token type: oauth2 ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.