> ## Documentation Index > Fetch the complete documentation index at: https://api-docs.helpyousponsor.com/llms.txt > Use this file to discover all available pages before exploring further. # Read a newsletter send-time recommendation > Returns a cached unexpired recommendation or computes one from tenant newsletter aggregates over the last 180days. Requires at least 50 delivered messages, 4 campaigns and 2 comparison slots with at least 2 campaigns each; latest delivery must be within 45days. The next winning local two-hour slot is at least 30minutes ahead. Results expire after one day. Insufficient/stale data and unexpected failures, including an invalid timezone, return 200 with a non-ready status; manual scheduling remains available. Requires permission: one of newsletter. ## OpenAPI ````yaml get /admin/newsLetters/timing-recommendation openapi: 3.0.0 info: title: Gratona API description: >- REST API for the Gratona fundraising platform, including donor, donation, sponsorship, program, event, and integration workflows. Endpoints are organized by tag. Most endpoints require either a Passport bearer token or an issued API key — see the Security Schemes section. contact: name: Gratona Engineering url: https://gratona.com email: devs@gratona.com version: 1.0.0 servers: - url: https://api.gratona.com/v1 description: Server Version 1.0.0 security: [] tags: - name: Auth description: >- Login, signup, logout, password reset, and email verification for admin users and donors. - name: Donors description: >- Donor records: CRUD, profile fields, household linkage, search, filters, merge, and duplicate detection. - name: Donations description: >- Individual donation records, recurring commitments, soft credits, refunds, designations, and exports. - name: Sponsorships description: >- Donor-to-entity commitment relationships, lifecycle transitions, and commitment-specific filters. - name: Entities description: >- Recipient records (children, families, projects, animals, etc.), their status, and entity-level fields. - name: Programs description: >- Program / campaign configuration: hierarchy, settings, and program-level metadata. - name: Forms description: >- Custom form builder (HysForm), form fields, standardized donor fields, and field migrations. - name: Trips description: >- Mission-trip management: trips, participants, budgets, tasks, e-signatures, fundraising milestones, and background checks. - name: Communications description: >- Email templates, SMS, newsletters, donor email manager, and per-donor notes. - name: Payments description: >- Payment-gateway management (Stripe, PayPal, Flutterwave, QuickBooks). Excludes inbound webhooks — see the Webhooks tag. - name: Reports description: Dashboards, analytics, scheduled reports, and exports. - name: Admin description: >- Client-account administration: users, groups/permissions, settings, integrations, and account lifecycle. - name: Donor Portal description: >- Endpoints consumed by the donor-facing portal (donor login, dashboard, donation history, messages). - name: Recipient Portal description: Endpoints consumed by the recipient-facing portal. - name: Public description: >- Unauthenticated public endpoints: donor signup, public trip pages, peer-to-peer campaigns, public checkout. - name: Webhooks description: >- Inbound webhooks from third parties (Stripe, PayPal, Flutterwave, Checkr, DropboxSign). Annotated minimally for reference; payload shapes are owned by the upstream provider. - name: Events description: >- Event setup, invitations, registration, ticketing, attendance and event reporting. - name: Journeys description: >- Journey graphs, activation, enrollment, message templates and event follow-up automations. - name: Tasks description: Workspace tasks, assignments, saved task views and record collaboration. - name: Fundraising description: >- Fundraising portfolios, stewardship plans, giving anniversaries and personal donor follow-up. - name: Impact Stories description: Story intake, review, assets, consent and publication workflows. - name: Integrations description: Workspace integration connections, mappings, synchronization and recovery. - name: Email Calendar description: Connected email/calendar accounts and donor interactions. - name: Spaces description: Workspace Spaces and collaborative Pages. - name: Library description: Workspace documents, source connections, files and analysis. - name: Intelligence description: Donor intelligence and Tali workspace workflows. - name: Automation description: >- V3 automation primitive discovery, input validation, invocation and Zapier contracts. - name: Schema description: V3 model, enum, capability and scope discovery. - name: Zapier description: Zapier automation connections, polling feeds and actions. - name: Files description: Files - name: Client description: Client - name: Payment Gateways description: Payment Gateways - name: Email Settings description: Email Settings - name: Admin Dashboard description: Admin Dashboard - name: Recipients description: Recipients - name: Historical Archived Updates description: Historical Archived Updates - name: Team & access description: Team & access - name: Settings description: Settings - name: Notifications description: Notifications - name: Participation description: Participation - name: Users description: Users - name: Wrapped description: Wrapped - name: Donor SignUp description: Donor SignUp - name: Frontend description: Frontend - name: User description: User - name: Workspace description: Workspace paths: /admin/newsLetters/timing-recommendation: get: tags: - Communications summary: Read a newsletter send-time recommendation description: >- Returns a cached unexpired recommendation or computes one from tenant newsletter aggregates over the last 180days. Requires at least 50 delivered messages, 4 campaigns and 2 comparison slots with at least 2 campaigns each; latest delivery must be within 45days. The next winning local two-hour slot is at least 30minutes ahead. Results expire after one day. Insufficient/stale data and unexpected failures, including an invalid timezone, return 200 with a non-ready status; manual scheduling remains available. Requires permission: one of newsletter. operationId: communicationsNewsletterTimingRecommendationShow parameters: - name: timezone in: query description: IANA timezone; defaults to organization timezone or UTC. required: false schema: type: string example: Africa/Kampala responses: '200': description: Operation result. content: application/json: schema: $ref: >- #/components/schemas/CommunicationsNewsletterTimingRecommendation '401': description: Authentication is required. content: application/json: schema: $ref: '#/components/schemas/UnauthorizedResponse' '403': description: >- The authenticated user lacks access to this workflow or its related records. '404': description: The organization is unavailable. content: application/json: schema: $ref: '#/components/schemas/NotFoundResponse' security: - bearerAuth: [] - apiKeyAuth: [] components: schemas: CommunicationsNewsletterTimingRecommendation: oneOf: - required: - status - data properties: status: type: string enum: - ready example: ready data: properties: id: type: string format: uuid example: 550e8400-e29b-41d4-a716-446655440000 resolvedAt: type: string format: date-time example: '2026-10-27T07:00:00Z' localDatetime: type: string example: '2026-10-27T10:00:00' timezone: type: string example: Africa/Kampala offsetMinutes: type: integer example: 180 confidence: type: string enum: - low - medium - high example: low basis: description: >- Aggregated newsletter history over 180 days; winningSlot appears for a ready recommendation. properties: deliveredMessages: type: integer example: 150 independentCampaigns: type: integer example: 6 comparisonSlots: type: integer example: 3 dataFrom: type: string format: date-time example: '2026-10-20T12:00:00Z' nullable: true dataTo: type: string format: date-time example: '2026-10-20T12:00:00Z' nullable: true requirements: properties: deliveredMessages: type: integer example: 50 independentCampaigns: type: integer example: 4 comparisonSlots: type: integer example: 2 maximumDataAgeDays: type: integer example: 45 type: object winningSlot: properties: weekday: type: integer maximum: 7 minimum: 1 example: 2 hour: type: integer maximum: 22 minimum: 0 example: 10 deliveredMessages: type: integer example: 100 independentCampaigns: type: integer example: 3 uniqueOpenRate: type: number example: 0.35 uniqueClickRate: type: number example: 0.05 type: object type: object generatedAt: type: string format: date-time example: '2026-10-20T12:00:00Z' nullable: true expiresAt: type: string format: date-time example: '2026-10-20T12:00:00Z' nullable: true algorithmVersion: type: string example: engagement-slots-v1 type: object type: object - required: - status - message properties: status: type: string enum: - insufficient_data - stale - unavailable example: insufficient_data message: type: string example: >- More varied newsletter history is needed before a recommendation is available. basis: description: >- Aggregated newsletter history over 180 days; winningSlot appears for a ready recommendation. properties: deliveredMessages: type: integer example: 150 independentCampaigns: type: integer example: 6 comparisonSlots: type: integer example: 3 dataFrom: type: string format: date-time example: '2026-10-20T12:00:00Z' nullable: true dataTo: type: string format: date-time example: '2026-10-20T12:00:00Z' nullable: true requirements: properties: deliveredMessages: type: integer example: 50 independentCampaigns: type: integer example: 4 comparisonSlots: type: integer example: 2 maximumDataAgeDays: type: integer example: 45 type: object winningSlot: properties: weekday: type: integer maximum: 7 minimum: 1 example: 2 hour: type: integer maximum: 22 minimum: 0 example: 10 deliveredMessages: type: integer example: 100 independentCampaigns: type: integer example: 3 uniqueOpenRate: type: number example: 0.35 uniqueClickRate: type: number example: 0.05 type: object type: object type: object UnauthorizedResponse: title: UnauthorizedResponse description: >- Returned with HTTP 401 when the request lacks a valid Passport bearer token, a valid `X-HYS-API-Key`, or a valid session. The body is the simple `{message, status}` envelope emitted by `AuthenticateApiOrKey`. required: - message - status properties: message: description: >- Always the literal string `Unauthorized` from the `auth.api_or_key` middleware. Login endpoints return `Invalid Credentials` instead. type: string example: Unauthorized status: type: string example: error type: object NotFoundResponse: title: NotFoundResponse description: >- Returned with HTTP 404 when a resource lookup misses (typically because the id doesn't exist OR is scoped to a different `client_id`). Note: many endpoints intentionally collapse 'not found' and 'forbidden' into a single 404 to avoid leaking which records exist in another tenant. required: - message properties: message: description: >- Human-readable message. Often a more specific string like `Donor not found` or `Trip not found`. type: string example: Not Found status: type: string example: error type: object securitySchemes: bearerAuth: type: http description: Passport bearer token authentication for legacy admin sessions. scheme: bearer bearerFormat: JWT apiKeyAuth: type: apiKey description: Gratona API key sent with the compatibility header X-HYS-API-Key. name: X-HYS-API-Key in: header ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.