Why actions and handlers defined separately?

This is one of the most interesting projects I've seen! Just want to make sure if I understand the logic behind json-render library (would be great if this repository would have Github Discussions).

My question is, why actions and handlers need to be defined separately?

const catalog = createCatalog({
  components: { /* ... */ },
  actions: {
    submit_form: {
      params: z.object({
        formId: z.string(),
      }),
      description: 'Submit a form',
    },
    export_data: {
      params: z.object({
        format: z.enum(['csv', 'pdf', 'json']),
        filters: z.object({
          dateRange: z.string().optional(),
        }).optional(),
      }),
    },
    navigate: {
      params: z.object({
        url: z.string(),
      }),
    },
  },
});

// ...
  const handlers = {
    submit_form: async (params) => {
      const response = await fetch('/api/submit', {
        method: 'POST',
        body: JSON.stringify({ formId: params.formId }),
      });
      return response.json();
    },
    
    export_data: async (params) => {
      const blob = await generateExport(params.format, params.filters);
      downloadBlob(blob, `export.${params.format}`);
    },
    
    navigate: (params) => {
      window.location.href = params.url;
    },
  };
// ...

Why not to use execute instead within actions object?

const catalog = createCatalog({
  components: { /* ... */ },
  actions: {
    submit_form: {
      params: z.object({
        formId: z.string(),
      }),
      description: 'Submit a form',
      execute: async (params) => {
        const response = await fetch('/api/submit', {
          method: 'POST',
          body: JSON.stringify({ formId: params.formId }),
        });
        return response.json();
      },
    },

The issue mentions createCatalog, actions, handlers, and a proposed execute field, but names no repository files or tests. Start by tracing those API entry points and comparing how action definitions and handlers are used; done should clearly document the rationale for keeping them separate or specify the supported alternative.