> ## Documentation Index > Fetch the complete documentation index at: https://docs.tinyfish.ai/llms.txt > Use this file to discover all available pages before exploring further. # Cancel run by ID > Cancel a run by ID. Only runs created via `/v1/automation/run-async` or `/v1/automation/run-sse` can be cancelled. Runs created via the synchronous `/v1/automation/run` endpoint cannot be cancelled. ## OpenAPI ````yaml https://agent.tinyfish.ai/v1/openapi/main post /v1/runs/{id}/cancel openapi: 3.0.0 info: title: TinyFish Web Agent Automation API version: 1.0.0 description: >- REST API for running AI-powered browser automations. Execute tasks on any website using natural language instructions. contact: name: TinyFish Support email: support@tinyfish.ai servers: - url: https://agent.tinyfish.ai description: Production security: [] tags: - name: Automation description: Browser automation endpoints for executing tasks on websites - name: Runs description: Endpoints for retrieving automation run data - name: Browser description: Remote browser session endpoints - name: Fetch description: Fetch URLs and extract clean page content - name: Search description: Web search endpoints - name: Browser Context Profiles description: >- Saved browser context endpoints for managing reusable login state, cookies, storage, and profile setup sessions - name: Vault description: >- Vault credential management endpoints for connecting password managers and managing stored credentials paths: /v1/runs/{id}/cancel: post: tags: - Runs summary: Cancel run by ID description: >- Cancel a run by ID. Only runs created via `/v1/automation/run-async` or `/v1/automation/run-sse` can be cancelled. Runs created via the synchronous `/v1/automation/run` endpoint cannot be cancelled. operationId: cancelRunById parameters: - schema: type: string pattern: ^[A-Za-z0-9_-]+$ description: Run ID example: a1b2c3d4-e5f6-7890-abcd-ef1234567890 required: true description: Run ID name: id in: path responses: '200': description: >- Run cancelled successfully, or already in terminal state (idempotent) content: application/json: schema: type: object properties: run_id: type: string description: The unique identifier of the run example: a1b2c3d4-e5f6-7890-abcd-ef1234567890 status: type: string enum: - CANCELLED - COMPLETED - FAILED description: >- The current status of the run. Returns actual status for idempotent responses (e.g., COMPLETED if run already finished) example: CANCELLED cancelled_at: type: string nullable: true description: >- ISO 8601 timestamp when the run was cancelled, or null if not cancelled example: '2026-01-14T10:30:55Z' message: type: string nullable: true description: >- Additional context about the cancellation result (e.g., "Run already cancelled", "Run already finished") example: Run already cancelled required: - run_id - status - cancelled_at - message description: Response from cancel run endpoint examples: cancelled: summary: Run cancelled value: run_id: a1b2c3d4-e5f6-7890-abcd-ef1234567890 status: CANCELLED cancelled_at: '2024-01-01T00:00:00Z' message: null alreadycancelled: summary: Run already cancelled (idempotent) value: run_id: a1b2c3d4-e5f6-7890-abcd-ef1234567890 status: CANCELLED cancelled_at: '2024-01-01T00:00:00Z' message: Run already cancelled alreadyCompleted: summary: Run already completed (no-op) value: run_id: a1b2c3d4-e5f6-7890-abcd-ef1234567890 status: COMPLETED cancelled_at: null message: Run already finished '401': description: Unauthorized - Invalid or missing API key content: application/json: schema: type: object properties: error: type: object properties: code: type: string enum: - MISSING_API_KEY - INVALID_API_KEY - INVALID_INPUT - RATE_LIMIT_EXCEEDED - INTERNAL_ERROR - RETRY_REQUIRED - UNAUTHORIZED - FORBIDDEN - NOT_FOUND - SERVICE_BUSY - TIMEOUT - INSUFFICIENT_CREDITS - CONTENT_POLICY_VIOLATION - MAX_STEPS_EXCEEDED - SITE_BLOCKED - TASK_FAILED - CANCELLED description: Machine-readable error code example: INVALID_INPUT message: type: string description: Human-readable error message example: Field "url" is required and must be a string details: nullable: true description: Additional error details (validation errors, etc.) required: - code - message required: - error description: Standard error response format '404': description: Run not found or not owned by this API key content: application/json: schema: type: object properties: error: type: object properties: code: type: string enum: - MISSING_API_KEY - INVALID_API_KEY - INVALID_INPUT - RATE_LIMIT_EXCEEDED - INTERNAL_ERROR - RETRY_REQUIRED - UNAUTHORIZED - FORBIDDEN - NOT_FOUND - SERVICE_BUSY - TIMEOUT - INSUFFICIENT_CREDITS - CONTENT_POLICY_VIOLATION - MAX_STEPS_EXCEEDED - SITE_BLOCKED - TASK_FAILED - CANCELLED description: Machine-readable error code example: INVALID_INPUT message: type: string description: Human-readable error message example: Field "url" is required and must be a string details: nullable: true description: Additional error details (validation errors, etc.) required: - code - message required: - error description: Standard error response format '500': description: Internal server error content: application/json: schema: type: object properties: error: type: object properties: code: type: string enum: - MISSING_API_KEY - INVALID_API_KEY - INVALID_INPUT - RATE_LIMIT_EXCEEDED - INTERNAL_ERROR - RETRY_REQUIRED - UNAUTHORIZED - FORBIDDEN - NOT_FOUND - SERVICE_BUSY - TIMEOUT - INSUFFICIENT_CREDITS - CONTENT_POLICY_VIOLATION - MAX_STEPS_EXCEEDED - SITE_BLOCKED - TASK_FAILED - CANCELLED description: Machine-readable error code example: INVALID_INPUT message: type: string description: Human-readable error message example: Field "url" is required and must be a string details: nullable: true description: Additional error details (validation errors, etc.) required: - code - message required: - error description: Standard error response format security: - ApiKeyAuth: [] components: securitySchemes: ApiKeyAuth: type: apiKey in: header name: X-API-Key description: API key for authentication. Get your key from the API Keys page. ````