> ## Documentation Index > Fetch the complete documentation index at: https://docs.textsetu.com/llms.txt > Use this file to discover all available pages before exploring further. # Add a language (manage) > Add a language to the project. Standard codes resolve to the shared global language; a non-standard code is created as an org custom language. Requires the `manage` scope — adding a language is a project-management operation, above ordinary `write`. PATs need the PROJECT_MANAGE permission — see [roles & permissions](/docs/guides/roles-and-permissions). ## OpenAPI ````yaml /openapi/textsetu.json post /projects/{projectId}/languages openapi: 3.1.0 info: title: TextSetu API version: 1.2.0 description: >- Public REST API for TextSetu. Authenticate with a Personal Access Token (tsu_pat_…) or a project token (tsu_proj_…) via the `Authorization: Bearer ` header. **Authorization is permission-based.** Every token carries an explicit allow-list of RBAC permission keys (e.g. `translation_read`), and each endpoint declares the permission it requires (`x-permission`). A token's effective access is its underlying authority ∩ its allow-list — a PAT is further bounded by its owner's role-based permissions, so it can only narrow, never exceed, what the owner already has. A project token is bound to a single project. There are no coarse read/write/manage scopes. **Response envelope.** Every endpoint returns `{ "success": true, "data": … }` on success and `{ "success": false, "error": { "code", "message" } }` on failure. **Rate limit.** 600 requests/minute, keyed by token (or by IP when unauthenticated). Exceeding it returns 429 with the standard error envelope. servers: - url: https://api.textsetu.com/api/v1 description: Production - url: /api/v1 description: This server (self-hosted / same-origin) security: - bearerAuth: [] tags: - name: Projects description: >- Read project metadata — settings, key separator, and the approval/branching flags that shape how the other endpoints behave. - name: Languages description: >- List and manage a project's target languages. Each language is referenced by its BCP-47 code; the source language is flagged separately. - name: Translations description: >- Manage a project's translations: create, read, update, and delete translation keys — the identifiers your app looks up, carrying metadata (description, tags, screenshot) — and set the translated value for a key in a given language. Value writes honor the project's approval workflow — non-approver writes land as `pending_review`. - name: Stats description: >- Per-language completeness and approval progress for a project — the numbers behind the dashboard. - name: Import/Export description: >- Bulk-load source files into a project or export the current translations. Supports the same file formats as the web app. - name: Branches description: >- Work on translations in isolation and merge them back. Branch reads/writes mirror the main endpoints but stage changes as a diff until merge. See the [branching guide](/docs/guides/branches). - name: Glossary description: >- Manage term bases — approved terminology and its translations — and check a string against them. See the [glossary guide](/docs/guides/glossary). - name: Translation Memory description: >- Reusable translation stores. Fuzzy-match and concordance-search prior translations to reuse them. See the [translation memory guide](/docs/guides/translation-memory). - name: AI description: >- Machine-translate a project with the org's configured AI engine (brand voice, glossary/TM grounding, and an optional review pass). Runs asynchronously — start a run and poll the returned `jobId`. - name: Webhooks description: >- Get notified when a project's translations change, instead of polling. Register an HTTPS endpoint, subscribe it to the events you care about, and TextSetu POSTs a signed payload whenever one occurs. Payloads follow the [Standard Webhooks](https://www.standardwebhooks.com) spec — verify the `webhook-signature` header with any compatible library. Delivery is at-least-once and unordered, so treat `webhook-id` as an idempotency key. Failed deliveries are retried five times over roughly seven hours, and every attempt is inspectable and replayable via the delivery log. - name: Meta description: Service-level and cross-cutting endpoints. paths: /projects/{projectId}/languages: post: tags: - Languages summary: Add a language (manage) description: >- Add a language to the project. Standard codes resolve to the shared global language; a non-standard code is created as an org custom language. Requires the `manage` scope — adding a language is a project-management operation, above ordinary `write`. PATs need the PROJECT_MANAGE permission — see [roles & permissions](/docs/guides/roles-and-permissions). parameters: - name: projectId in: path required: true schema: type: string description: Project id (UUID) or id-embedded path slug. requestBody: required: true content: application/json: schema: type: object properties: languageCode: type: string minLength: 2 maxLength: 10 description: BCP-47 language code to add to the project. examples: - fr label: type: string minLength: 1 maxLength: 100 description: Display name for the language. examples: - French isSource: description: >- Mark this as the project's source language (only one may be the source). type: boolean required: - languageCode - label responses: '201': description: The newly added project language. content: application/json: schema: type: object required: - success - data properties: success: type: boolean const: true data: type: object properties: language: type: object properties: id: type: string description: Unique id of this project-language row (UUID). examples: - pl_1a2b3c4d projectId: type: string description: Id of the project this language belongs to. examples: - proj_9f8e7d6c languageCode: type: string description: BCP-47 language code, e.g. `en` or `fr`. examples: - fr label: type: string description: >- Human-readable language name, resolved from the org language catalog. examples: - French isSource: type: boolean description: >- True if this is the project's source (reference) language. examples: - false createdAt: type: string description: Creation timestamp (ISO 8601). examples: - '2026-01-15T09:24:00.000Z' updatedAt: type: string description: Last-update timestamp (ISO 8601). examples: - '2026-02-02T14:05:00.000Z' required: - id - projectId - languageCode - label - isSource - createdAt - updatedAt additionalProperties: false required: - language additionalProperties: false '500': description: Failed to add the language. components: securitySchemes: bearerAuth: type: http scheme: bearer description: >- API token: tsu_pat_… (PAT) or tsu_proj_… (project token). The token's granted RBAC permissions determine access; see each operation's `x-permission`. ````