How to add custom Search Attributes to Workflow Executions at start time in TypeScript

Use WorkflowOptions.searchAttributes.

search-attributes/src/client.ts

TypeScript

const handle = await client.start(example, {
    taskQueue: 'search-attributes',
    workflowId: 'search-attributes-example-0',
    searchAttributes: {
      CustomIntField: [2],
      CustomKeywordField: ['keywordA', 'keywordB'],
      CustomBoolField: [true],
      CustomDatetimeField: [new Date()],
      CustomStringField: [
        'String field is for text. When queried, it will be tokenized for partial match. StringTypeField cannot be used in Order By',
      ],
    },
  });

  const { searchAttributes } = await handle.describe();

JavaScript

const handle = await client.start(example, {
  taskQueue: 'search-attributes',
  workflowId: 'search-attributes-example-0',
  searchAttributes: {
    CustomIntField: [2],
    CustomKeywordField: ['keywordA', 'keywordB'],
    CustomBoolField: [true],
    CustomDatetimeField: [new Date()],
    CustomStringField: [
      'String field is for text. When queried, it will be tokenized for partial match. StringTypeField cannot be used in Order By',
    ],
  },
});

const { searchAttributes } = await handle.describe();

The type of searchAttributes is Record<string, string[] | number[] | boolean[] | Date[]>.