> ## Documentation Index > Fetch the complete documentation index at: https://docs.gc.ai/llms.txt > Use this file to discover all available pages before exploring further. # Search Chats > Hybrid search across the caller's chat history that merges two lanes: a case-insensitive title-substring match and a semantic (vector) match over each chat's AI-generated summary. Title matches are returned first (a strong signal the user remembers the chat name), followed by semantic matches in relevance order, de-duplicated and capped at `limit`. **Authorization:** User-scoped keys (`u:gcai_...`) search the chats that user can access. Organization-scoped keys search every chat shared with the entire organization, regardless of who or what created it. Chats that remain private to an individual user are never returned to an org-scoped key. API-created chats appear here only once they've been [materialized](/api-reference/concepts/chat-visibility); unmaterialized chats are not in anyone's history and won't match. ## OpenAPI ````yaml GET /chat/search openapi: 3.0.3 info: title: GC AI External API version: 1.0.0 description: >- The GC AI External API allows programmatic access to GC AI's chat capabilities. It's designed for integration with workflow automation tools like Zapier, Make, n8n, or custom applications. ## Authentication All API requests must include an API key in the `Authorization` header: ``` Authorization: gcai_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ``` API keys can be created in the GC AI app under **Settings → API**. ## Current Limitations The API is optimized for single-turn completions. The following are not yet available via API: - **Multi-turn conversations**: each request is independent - **Interactive clarification**: the model cannot pause to ask the caller a follow-up question; the `askUserQuestions` tool is disabled on the API surface in beta ## Usage Usage is tracked and viewable in the GC AI app under **Settings → API → View Usage**. ## Support For API support, contact [support@gc.ai](mailto:support@gc.ai) or reach out to your account representative. contact: email: support@gc.ai servers: - url: https://app.gc.ai/api/external/v1 description: Production server security: [] tags: - name: Chat description: AI chat completion endpoints - name: Files description: File upload and management endpoints - name: Folders description: Folder management endpoints - name: Playbooks description: Playbook review endpoints - name: Projects description: Project management endpoints - name: Utility description: Health check and connectivity endpoints paths: /chat/search: get: tags: - Chat summary: Search chats description: >- Hybrid search across the caller's chat history that merges two lanes: a case-insensitive title-substring match and a semantic (vector) match over each chat's AI-generated summary. Title matches are returned first (a strong signal the user remembers the chat name), followed by semantic matches in relevance order, de-duplicated and capped at `limit`. **Authorization:** User-scoped keys (`u:gcai_...`) search the chats that user can access. Organization-scoped keys search every chat shared with the entire organization, regardless of who or what created it. Chats that remain private to an individual user are never returned to an org-scoped key. API-created chats appear here only once they've been [materialized](/api-reference/concepts/chat-visibility); unmaterialized chats are not in anyone's history and won't match. operationId: searchChats parameters: - schema: type: string minLength: 1 maxLength: 500 description: Search query (required, 1-500 chars). Natural language is fine. example: force majeure carve-out required: true description: Search query (required, 1-500 chars). Natural language is fine. name: q in: query - schema: type: integer minimum: 1 maximum: 50 default: 20 description: Max chats to return (default 20, max 50) required: false description: Max chats to return (default 20, max 50) name: limit in: query responses: '200': description: Chats matching the query content: application/json: schema: $ref: '#/components/schemas/ChatSearchResponse' '400': description: Missing or invalid query parameters content: application/json: schema: $ref: '#/components/schemas/Error' '401': description: Missing or malformed API key content: application/json: schema: $ref: '#/components/schemas/Error' '403': description: Invalid API key content: application/json: schema: $ref: '#/components/schemas/Error' '500': description: Internal server error content: application/json: schema: $ref: '#/components/schemas/Error' '503': description: Service temporarily unavailable headers: Retry-After: schema: type: string description: >- Seconds to wait before retrying after a transient service outage. example: '5' required: true description: >- Seconds to wait before retrying after a transient service outage. content: application/json: schema: $ref: '#/components/schemas/Error' security: - ApiKeyAuth: [] components: schemas: ChatSearchResponse: type: object properties: chats: type: array items: $ref: '#/components/schemas/ChatSearchResult' description: >- Chats matching the query. Title-substring matches first, then semantic (vector) matches in relevance order, de-duplicated and capped at `limit`. required: - chats Error: type: object properties: error: type: string description: Error message message: type: string description: Additional error details details: type: object additionalProperties: nullable: true description: Validation error details (for 400 errors) required: - error ChatSearchResult: type: object properties: id: type: string format: uuid description: Unique chat identifier title: type: string nullable: true description: Chat title, or null if untitled summary: type: string nullable: true description: AI-generated summary of the chat, if any updated_at: type: string description: ISO 8601 last-update timestamp required: - id - title - summary - updated_at securitySchemes: ApiKeyAuth: type: apiKey in: header name: Authorization description: |- API key for authentication. Format: `gcai_xxxxxxxxx` Create API keys in the GC AI app under Settings → API. ````