> ## Documentation Index > Fetch the complete documentation index at: https://docs.freyavoice.ai/llms.txt > Use this file to discover all available pages before exploring further. # Replace TTS abbreviations > Replaces the TTS abbreviations list (`textSubstitutions`) on an agent or on a workflow's embedded agent config. Behaves like a UI save: persists to the JSONB config and creates a new version for audit and rollback. Identify the target by either `id` (UUID, preferred) or `name`. The resolver checks agents first, then workflows, so `id` is unambiguous. If `name` is provided and it matches multiple rows in either table, or matches both an agent and a workflow, the request fails with 409 — pass `id` to disambiguate. The full `abbreviations` list is replaced — there is no per-rule patch. ## OpenAPI ````yaml https://staging-app.freyavoice.ai/api/openapi.json put /custom/abbreviations openapi: 3.1.0 info: title: Freyavoice API version: 2.0.0 description: >- Production API for managing calls and campaigns. **Authentication**: All endpoints require a bearer token issued by Freyavoice. **Response Format**: All responses are wrapped in a standard envelope: ```json { "success": true, "data": { "message": "Success", "result": { /* endpoint-specific data */ } } } ``` Error responses follow the same format with `success: false`: ```json { "success": false, "data": { "message": "Error description", "result": null } } ``` contact: name: Freyavoice Support email: support@freyavoice.com servers: - url: https://app.freyavoice.ai/api/v2 description: Production security: [] tags: - name: Agents description: Manage AI agents - name: Analytics description: Call analytics and metrics - name: API Keys description: API key management - name: Audio description: Audio transcription and speech synthesis - name: Calls description: Call management and history - name: Call Recordings description: Call recording management - name: Call Tags description: Call tagging and categorization - name: Campaigns description: Campaign management - name: Chat description: Stateful text chat with agents and workflows - name: Custom description: Custom convenience endpoints - name: Export description: Data export - name: Insights description: Structured data field definitions - name: Agent Insights description: Agent-to-field assignments - name: Integrations description: Third-party integrations - name: Personas description: Simulation personas for agent testing - name: Phone Numbers description: Phone number management - name: Phone Aliases description: Workspace phone book (phone-number to label mappings) - name: Suppression List description: Workspace do-not-call (DNC) list; numbers blocked from outbound dialing - name: Feedbacks description: Feedback tracking - name: Feedback Assignees description: Feedback assignment - name: Feedback Comments description: Feedback comments - name: Feedback References description: Feedback cross-references to other entities - name: Feedback Status Config description: Feedback status configuration - name: Reviews description: Call reviews - name: Review Assignees description: Review assignment - name: Simulations description: Agent simulation testing - name: Simulation Iterations description: Simulation iteration history - name: Unit Tests description: Behavioural unit tests for agents and workflows - name: Branches description: Branches (proposed changes) of an agent or workflow version line - name: Webhooks description: Webhook configuration - name: Versions description: Version history and rollback for agents and workflows - name: Workflows description: Workflow management - name: Workspaces description: Workspace management - name: Workspace Credits description: Workspace credit balance - name: Workspace Invitations description: Workspace invitations - name: Workspace Logs description: Workspace activity logs - name: Workspace Members description: Workspace member management - name: Workspace Roles description: Custom roles and permissions per workspace - name: Permissions description: Permission catalog (used by role + API-key UIs) paths: /custom/abbreviations: put: tags: - Custom summary: Replace TTS abbreviations description: >- Replaces the TTS abbreviations list (`textSubstitutions`) on an agent or on a workflow's embedded agent config. Behaves like a UI save: persists to the JSONB config and creates a new version for audit and rollback. Identify the target by either `id` (UUID, preferred) or `name`. The resolver checks agents first, then workflows, so `id` is unambiguous. If `name` is provided and it matches multiple rows in either table, or matches both an agent and a workflow, the request fails with 409 — pass `id` to disambiguate. The full `abbreviations` list is replaced — there is no per-rule patch. operationId: putCustomAbbreviations requestBody: content: application/json: schema: type: object properties: id: type: string format: uuid name: type: string minLength: 1 maxLength: 200 abbreviations: type: array items: type: object properties: pattern: type: string minLength: 1 maxLength: 500 replacement: type: string maxLength: 500 caseInsensitive: type: boolean required: - pattern - replacement required: - abbreviations example: workspaceId: 550e8400-e29b-41d4-a716-446655440000 id: 650e8400-e29b-41d4-a716-446655440000 abbreviations: - pattern: AI replacement: A I caseInsensitive: true - pattern: \$ replacement: dollars responses: '200': description: Abbreviations updated content: application/json: schema: type: object properties: success: type: boolean enum: - true data: type: object properties: message: type: string result: type: object properties: type: type: string enum: - agent - workflow id: type: string format: uuid name: type: string versionId: type: - string - 'null' format: uuid abbreviations: type: array items: type: object properties: pattern: type: string minLength: 1 maxLength: 500 replacement: type: string maxLength: 500 caseInsensitive: type: boolean required: - pattern - replacement required: - type - id - name - versionId - abbreviations required: - message - result required: - success - data '400': description: Validation error content: application/json: schema: type: object properties: success: type: boolean enum: - false data: type: object properties: message: type: string result: {} required: - message required: - success - data '401': description: Missing or invalid token content: application/json: schema: type: object properties: success: type: boolean enum: - false data: type: object properties: message: type: string result: {} required: - message required: - success - data '403': description: Workspace ID mismatch or insufficient permissions content: application/json: schema: type: object properties: success: type: boolean enum: - false data: type: object properties: message: type: string result: {} required: - message required: - success - data '404': description: Target agent or workflow not found '409': description: Target name is ambiguous within the workspace '500': description: Server error content: application/json: schema: type: object properties: success: type: boolean enum: - false data: type: object properties: message: type: string result: {} required: - message required: - success - data security: - bearerAuth: [] components: securitySchemes: bearerAuth: type: http scheme: bearer ````